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Fermoyle CC, La Salle DT, Alpenglow JK, Craig JC, Jarrett CL, Broxterman RM, McKenzie AI, Morgan DE, Birgenheier NM, Wray DW, Richardson RS, Trinity JD. Pharmacological modulation of adrenergic tone alters the vasodilatory response to passive leg movement in young but not in old adults. J Appl Physiol (1985) 2023; 134:1124-1134. [PMID: 36927146 PMCID: PMC10125034 DOI: 10.1152/japplphysiol.00682.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 03/06/2023] [Accepted: 03/10/2023] [Indexed: 03/18/2023] Open
Abstract
The age-related increase in α-adrenergic tone may contribute to decreased leg vascular conductance (LVC) both at rest and during exercise in the old. However, the effect on passive leg movement (PLM)-induced LVC, a measure of vascular function, which is markedly attenuated in this population, is unknown. Thus, in eight young (25 ± 5 yr) and seven old (65 ± 7 yr) subjects, this investigation examined the impact of systemic β-adrenergic blockade (propanalol, PROP) alone, and PROP combined with either α1-adrenergic stimulation (phenylephrine, PE) or α-adrenergic inhibition (phentolamine, PHEN), on PLM-induced vasodilation. LVC, calculated from femoral artery blood flow and pressure, was determined and PLM-induced Δ peak (LVCΔpeak) and total vasodilation (LVCAUC, area under curve) were documented. PROP decreased LVCΔpeak (PROP: 4.8 ± 1.8, Saline: 7.7 ± 2.7 mL·mmHg-1, P < 0.001) and LVCAUC (PROP: 1.1 ± 0.7, Saline: 2.4 ± 1.6 mL·mmHg-1, P = 0.002) in the young, but not in the old (LVCΔpeak, P = 0.931; LVCAUC, P = 0.999). PE reduced baseline LVC (PE: 1.6 ± 0.4, PROP: 2.3 ± 0.4 mL·min-1·mmHg-1, P < 0.01), LVCΔpeak (PE: 3.2 ± 1.3, PROP: 4.8 ± 1.8 mL·min-1·mmHg-1, P = 0.004), and LVCAUC (PE: 0.5 ± 0.4, PROP: 1.1 ± 0.7 mL·mmHg-1, P = 0.011) in the young, but not in the old (baseline LVC, P = 0.199; LVCΔpeak, P = 0.904; LVCAUC, P = 0.823). PHEN increased LVC at rest and throughout PLM in both groups (drug effect: P < 0.05), however LVCΔpeak was only improved in the young (PHEN: 6.4 ± 3.1, PROP: 4.4 ± 1.5 mL·min-1·mmHg-1, P = 0.004), and not in the old (P = 0.904). Furthermore, the magnitude of α-adrenergic modulation (PHEN - PE) of LVCΔpeak was greater in the young compared with the old (Young: 3.35 ± 2.32, Old: 0.40 ± 1.59 mL·min-1·mmHg-1, P = 0.019). Therefore, elevated α-adrenergic tone does not appear to contribute to the attenuated vascular function with age identified by PLM.NEW & NOTEWORTHY Stimulation of α1-adrenergic receptors eliminated age-related differences in passive leg movement (PLM) by decreasing PLM-induced vasodilation in the young. Systemic β-blockade attenuated the central hemodynamic component of the PLM response in young individuals. Inhibition of α-adrenergic receptors did not improve the PLM response in older individuals, though withdrawal of α-adrenergic modulation augmented baseline and maximal vasodilation in both groups. Accordingly, α-adrenergic signaling plays a role in modulating the PLM vasodilatory response in young but not in old adults, and elevated α-adrenergic tone does not appear to contribute to the attenuated vascular function with age identified by PLM.
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Affiliation(s)
- Caitlin C Fermoyle
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
| | - D Taylor La Salle
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Jeremy K Alpenglow
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Jesse C Craig
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
| | - Catherine L Jarrett
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
| | - Ryan M Broxterman
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Alec I McKenzie
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
| | - David E Morgan
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
| | - Nathaniel M Birgenheier
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
| | - D Walter Wray
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Russell S Richardson
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
| | - Joel D Trinity
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen VA Medical Center, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
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Alpenglow J, Bunsawat K, Fancisco M, Weavil J, Broxterman R, Iacovelli J, Harrison J, Morgan DE, Ryan JJ, Ma CL, Wray DW. Skeletal Muscle Oxygen Delivery and Utilization during Exercise in Heart Failure with Preserved Ejection Fraction: Role of Sympathetic (α‐adrenergic) Vasoconstriction. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r2459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jeremy Alpenglow
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | | | - Michael Fancisco
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterUniversity of UtahSalt Lake CityUT
| | - Josh Weavil
- AnesthesiologyUniversity of UtahSalt Lake CityUT
| | - Ryan Broxterman
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterUniversity of UtahSalt Lake CityUT
| | - Jarred Iacovelli
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Jon Harrison
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | | | - John J. Ryan
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Chisty L. Ma
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - D. W. Wray
- Geriatric Research, Education, and Clinical CenterSLC VAMCSalt Lake CityUT
- Internal MedicineSLC VAMCSalt Lake CityUT
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Pollard JE, Smith DW, Morgan DE, Skaggs JD. Combined use of a Total Control Introducer and a hyperangulated video laryngoscope to place a left-sided double lumen endotracheal tube in a patient with a history of difficult laryngoscopy. BMJ Case Rep 2021; 14:14/10/e243407. [PMID: 34625438 PMCID: PMC8504176 DOI: 10.1136/bcr-2021-243407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
We describe the use of a Total Control Introducer (TCI) in combination with video laryngoscopy (VL) to place a left-sided double-lumen endotracheal tube (DLT) in a patient with a history of difficult laryngoscopy undergoing video-assisted thoracoscopic surgery (VATS). VL was used to obtain visualisation of the glottis and a TCI articulating introducer was used to dynamically navigate the airway and access the trachea. A 39 French DLT was subsequently passed over the TCI shaft and into the trachea under indirect visualisation. The TCI shaft was removed and the DLT was gently guided into the left main bronchus. Successful endobronchial intubation was confirmed with capnography, auscultation and fibreoptic bronchoscopy. We propose that the combined use of VL and a TCI can facilitate placement of a DLT in a patient with a known difficult airway who may otherwise be limited to a bronchial blocker placement for lung isolation during VATS.
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Affiliation(s)
- Jacob E Pollard
- Anesthesiology, University of Utah Health Hospitals and Clinics, Salt Lake City, Utah, USA
| | - D Warner Smith
- Anesthesiology, University of Utah Health Hospitals and Clinics, Salt Lake City, Utah, USA
| | - David E Morgan
- Anesthesiology, University of Utah Health Hospitals and Clinics, Salt Lake City, Utah, USA
| | - John D Skaggs
- Anesthesiology, University of Utah Health Hospitals and Clinics, Salt Lake City, Utah, USA
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Trinity JD, Kwon OS, Broxterman RM, Gifford JR, Kithas AC, Hydren JR, Jarrett CL, Shields KL, Bisconti AV, Park SH, Craig JC, Nelson AD, Morgan DE, Jessop JE, Bledsoe AD, Richardson RS. The role of the endothelium in the hyperemic response to passive leg movement: looking beyond nitric oxide. Am J Physiol Heart Circ Physiol 2020; 320:H668-H678. [PMID: 33306447 DOI: 10.1152/ajpheart.00784.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Passive leg movement (PLM) evokes a robust and predominantly nitric oxide (NO)-mediated increase in blood flow that declines with age and disease. Consequently, PLM is becoming increasingly accepted as a sensitive assessment of endothelium-mediated vascular function. However, a substantial PLM-induced hyperemic response is still evoked despite nitric oxide synthase (NOS) inhibition. Therefore, in nine young healthy men (25 ± 4 yr), this investigation aimed to determine whether the combination of two potent endothelium-dependent vasodilators, specifically prostaglandin (PG) and endothelium-derived hyperpolarizing factor (EDHF), account for the remaining hyperemic response to the two variants of PLM, PLM (60 movements) and single PLM (sPLM, 1 movement), when NOS is inhibited. The leg blood flow (LBF, Doppler ultrasound) response to PLM and sPLM following the intra-arterial infusion of NG-monomethyl-l-arginine (l-NMMA), to inhibit NOS, was compared to the combined inhibition of NOS, cyclooxygenase (COX), and cytochrome P-450 (CYP450) by l-NMMA, ketorolac tromethamine (KET), and fluconazole (FLUC), respectively. NOS inhibition attenuated the overall LBF [area under the curve (LBFAUC)] response to both PLM (control: 456 ± 194, l-NMMA: 168 ± 127 mL, P < 0.01) and sPLM (control: 185 ± 171, l-NMMA: 62 ± 31 mL, P = 0.03). The combined inhibition of NOS, COX, and CYP450 (i.e., l-NMMA+KET+FLUC) did not further attenuate the hyperemic responses to PLM (LBFAUC: 271 ± 97 mL, P > 0.05) or sPLM (LBFAUC: 72 ± 45 mL, P > 0.05). Therefore, PG and EDHF do not collectively contribute to the non-NOS-derived NO-mediated, endothelium-dependent hyperemic response to either PLM or sPLM in healthy young men. These findings add to the mounting evidence and understanding of the vasodilatory pathways assessed by the PLM and sPLM vascular function tests.NEW & NOTEWORTHY Passive leg movement (PLM) evokes a highly nitric oxide (NO)-mediated hyperemic response and may provide a novel evaluation of vascular function. The contributions of endothelium-dependent vasodilatory pathways, beyond NO and including prostaglandins and endothelium-derived hyperpolarizing factor, to the PLM-induced hyperemic response to PLM have not been evaluated. With intra-arterial drug infusion, the combined inhibition of nitric oxide synthase (NOS), cyclooxygenase, and cytochrome P-450 (CYP450) pathways did not further diminish the hyperemic response to PLM compared with NOS inhibition alone.
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Affiliation(s)
- Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Oh Sung Kwon
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Kinesiology, University of Connecticut, Storrs, Connecticut
| | - Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Exercise Science, Brigham Young University, Provo, Utah
| | - Andrew C Kithas
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Catherine L Jarrett
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Katherine L Shields
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Angela V Bisconti
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Jesse C Craig
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Ashley D Nelson
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Department of Veterans Affairs Medical Center, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
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5
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Box EW, Deng L, Morgan DE, Xie R, Kirklin JK, Wang TN, Heslin MJ, Reddy S, Vickers S, Dudeia V, Rose JB. Preoperative anthropomorphic radiographic measurements can predict postoperative pancreatic fistula formation following pancreatoduodenectomy. Am J Surg 2020; 222:133-138. [PMID: 33390246 DOI: 10.1016/j.amjsurg.2020.10.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 10/06/2020] [Accepted: 10/19/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Postoperative pancreatic fistulae (POPF) are a major contributing factor to pancreatoduodenectomy-associated morbidity. Established risk calculators mostly rely on subjective or intraoperative assessments. We hypothesized that various objective preoperatively determined computed tomography (CT) measurements could predict POPF as well as validated models and allow for more informed operative consent in high-risk patients. METHODS Patients undergoing elective pancreatoduodenectomies between January 2013 and April 2018 were identified in a prospective database. Comparative statistical analyses and multivariable logistic regression models were generated to predict POPF development. Model performance was tested with receiver operating characteristics (ROC) curves. Pancreatic neck attenuation (Hounsfield units) was measured in triplicate by pancreatic protocol CT (venous phase, coronal plane) anterior to the portal vein. A pancreatic density index (PDI) was created to adjust for differences in contrast timing by dividing the mean of these measurements by the portal vein attenuation. Total areas of subcutaneous fat and skeletal muscle were calculated at the L3 vertebral level on axial CT. Pancreatic duct (PD) diameter was determined by CT. RESULTS In the study period 220 patients had elective pancreatoduodenectomies with 35 (16%) developing a POPF of any grade. Multivariable regression analysis revealed that demographics (age, sex, and race) were not associated with POPF, yet patients resected for pancreatic adenocarcinoma or chronic pancreatitis were less likely to develop a POPF (10 vs. 24%; p = 0.004). ROC curves were created using various combinations of gland texture, body mass index, skeletal muscle index, sarcopenia, PDI, PD diameter, and subcutaneous fat area indexed for height (SFI). A model replacing gland texture with SFI and PDI (AUC 0.844) had similar predictive performance as the established model (p = 0.169). CONCLUSION A combination of preoperative objective CT measurements can adequately predict POPF and is comparable to established models relying on subjective intraoperative variables. Validation in a larger dataset would allow for better preoperative stratification of high-risk patients and improve informed consent among this patient population.
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Affiliation(s)
- E W Box
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - L Deng
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - D E Morgan
- Department of Radiology, University of Alabama at Birmingham, 500 22nd Street South, Birmingham, AL, 35233, USA
| | - R Xie
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - J K Kirklin
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - T N Wang
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - M J Heslin
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - S Reddy
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - S Vickers
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - V Dudeia
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA
| | - J B Rose
- Department of Surgery, University of Alabama at Birmingham, Boshell Diabetes Building #618, 1808 7th Ave. S, Birmingham, AL, 35233, USA.
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Kithas AC, Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Hydren JR, Nelson AD, Jessop JE, Bledsoe AD, Morgan DE, Richardson RS. Nitric oxide synthase inhibition with N(G)-monomethyl-l-arginine: Determining the window of effect in the human vasculature. Nitric Oxide 2020; 104-105:51-60. [PMID: 32979497 DOI: 10.1016/j.niox.2020.09.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/07/2020] [Accepted: 09/21/2020] [Indexed: 11/17/2022]
Abstract
Nitric oxide synthase (NOS) inhibition with N(G)-monomethyl-l-arginine (L-NMMA) is often used to assess the role of NO in human cardiovascular function. However, the window of effect for L-NMMA on human vascular function is unknown, which is critical for designing and interpreting human-based studies. This study utilized the passive leg movement (PLM) assessment of vascular function, which is predominantly NO-mediated, in 7 young male subjects under control conditions, immediately following intra-arterial L-NMMA infusion (0.24 mg⋅dl-1⋅min-1), and at 45-60 and 90-105 min post L-NMMA infusion. The leg blood flow (LBF) and leg vascular conductance (LVC) responses to PLM, measured with Doppler ultrasound and expressed as the change from baseline to peak (ΔLBFpeak and ΔLVCpeak) and area under the curve (LBFAUC and LVCACU), were assessed. PLM-induced robust control ΔLBFpeak (1135 ± 324 ml⋅min-1) and ΔLVCpeak (10.7 ± 3.6 ml⋅min-1⋅mmHg-1) responses that were significantly attenuated (704 ± 196 ml⋅min-1 and 6.7 ± 2 ml⋅min-1⋅mmHg-1) immediately following L-NMMA infusion. Likewise, control condition PLM ΔLBFAUC (455 ± 202 ml) and ΔLVCAUC (4.0 ± 1.4 ml⋅mmHg-1) were significantly attenuated (141 ± 130 ml and 1.3 ± 1.2 ml⋅mmHg-1) immediately following L-NMMA infusion. However, by 45-60 min post L-NMMA infusion all PLM variables were not significantly different from control, and this was still the case at 90-105 min post L-NMMA infusion. These findings reveal that the potent reduction in NO bioavailability afforded by NOS inhibition with L-NMMA has a window of effect of less than 45-60 min in the human vasculature. These data are particularly important for the commonly employed approach of pharmacologically inhibiting NOS with L-NMMA in the human vasculature.
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Affiliation(s)
- Andrew C Kithas
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Ryan M Broxterman
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA
| | - Joel D Trinity
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA
| | - Jayson R Gifford
- Department of Exercise Sciences, Brigham Young University, Provo, UT, USA
| | - Oh Sung Kwon
- Department of Kinesiology, University of Connecticut, Storrs, CT, USA
| | - Jay R Hydren
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA
| | - Ashley D Nelson
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Jacob E Jessop
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Amber D Bledsoe
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - David E Morgan
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA; Department of Nutrition and Integrative Physiology, USA; Geriatric Research, Education, and Clinical Center, Salt Lake City, VAMC, UT, USA.
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7
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Cho JM, Park SK, La Salle DT, Cerbie J, Bledsoe A, Nelson A, Morgan DE, Richardson RS, Shiu YT, Boudina S, Trinity JD, Symons JD. Age‐associated Arterial Dysfunction is Rejuvenated by Targeted Reactivation of Protein Kinase Cδ. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.02731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Craig JC, Broxterman RM, La Salle DT, Cerbie J, Ratchford SM, Gifford JR, Bunsawat K, Nelson AD, Bledsoe AD, Morgan DE, Wray DW, Richardson RS, Trinity JD. The role of endothelin A receptors in peripheral vascular control at rest and during exercise in patients with hypertension. J Physiol 2019; 598:71-84. [PMID: 31705661 DOI: 10.1113/jp279077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 11/01/2019] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS Exercise in patients with hypertension can be accompanied by an abnormal cardiovascular response that includes attenuated blood flow and an augmented pressor response. Endothelin-1, a very potent vasoconstrictor, is a key modulator of blood flow and pressure during in health and has been implicated as a potential cause of the dysfunction in hypertension. We assessed the role of endothelin-1, acting through endothelin A (ETA ) receptors, in modulating the central and peripheral cardiovascular responses to exercise in patients with hypertension via local antagonism of these receptors during exercise. ETA receptor antagonism markedly increased leg blood flow, vascular conductance, oxygen delivery, and oxygen consumption during exercise; interestingly, these changes occurred in the presence of reduced leg perfusion pressure, indicating that these augmentations were driven by changes in vascular resistance. These data indicate that ETA receptor antagonism could be a viable therapeutic approach to improve blood flow during exercise in hypertension. ABSTRACT Patients with hypertension can exhibit impaired muscle blood flow and exaggerated increases in blood pressure during exercise. While endothelin (ET)-1 plays a role in regulating blood flow and pressure during exercise in health, little is known about the role of ET-1 in the cardiovascular response to exercise in hypertension. Therefore, eight volunteers diagnosed with hypertension were studied during exercise with either saline or BQ-123 (ETA receptor antagonist) infusion following a 2-week withdrawal of anti-hypertensive medications. The common femoral artery and vein were catheterized for drug infusion, blood collection and blood pressure measurements, and leg blood flow was measured by Doppler ultrasound. Patients exercised at both absolute (0, 5, 10, 15 W) and relative (40, 60, 80% peak power) intensities. BQ-123 increased blood flow at rest (79 ± 87 ml/min; P = 0.03) and augmented the exercise-induced hyperaemia at most intensities (80% saline: Δ3818±1222 vs. BQ-123: Δ4812±1469 ml/min; P = 0.001). BQ-123 reduced leg MAP at rest (-8 ± 4 mmHg; P < 0.001) and lower intensities (0-10 W; P < 0.05). Systemic diastolic blood pressure was reduced (0 W, 40%; P < 0.05), but systemic MAP was defended by an increased cardiac output. The exercise pressor response (ΔMAP) did not differ between conditions (80% saline: 25 ± 10, BQ-123: 30 ± 7 mmHg; P = 0.17). Thus, ET-1, acting through the ETA receptors, contributes to the control of blood pressure at rest and lower intensity exercise in these patients. Furthermore, the finding that ET-1 constrains the blood flow response to exercise suggests that ETA receptor antagonism could be a therapeutic approach to improve blood flow during exercise in hypertension.
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Affiliation(s)
- Jesse C Craig
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Ryan M Broxterman
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - D Taylor La Salle
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - James Cerbie
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Stephen M Ratchford
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Jayson R Gifford
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA
| | - Kanokwan Bunsawat
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Ashley D Nelson
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah, USA
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah, USA
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah, USA
| | - D Walter Wray
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Russell S Richardson
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Joel D Trinity
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
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9
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Park S, La Salle DT, Cerbie J, Cho JM, Bledsoe A, Nelson A, Morgan DE, Richardson RS, Shiu Y, Boudina S, Trinity JD, Symons JD. Evidence for an Age‐Associated Impairment of Exercise‐Induced Autophagy and eNOS Activation in Primary Arterial Endothelial Cells from Humans. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.696.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Seul‐Ki Park
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - D. Taylor La Salle
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - James Cerbie
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Jae Min Cho
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Amber Bledsoe
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Ashely Nelson
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - David E. Morgan
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Russell S. Richardson
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Yan‐Ting Shiu
- Division of Nephrology and Hypertension, Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Sihem Boudina
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Joel D. Trinity
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center; and Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - J. David Symons
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
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10
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Craig JC, Broxterman RM, La Salle DT, Cerbie J, Ratchford SM, Gifford JR, Bunsawat K, Nelson AD, Bledsoe AD, Morgan DE, Wray DW, Richardson RS, Trinity JD. The Role of Endothelin‐1 in Exercising Blood Flow and Blood Pressure Regulation in Patients with Hypertension. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.696.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Ryan M Broxterman
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - D Taylor La Salle
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - James Cerbie
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Stephen M Ratchford
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Jayson R Gifford
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | | | | | | | | | - D Walter Wray
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Russell S Richardson
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Joel D Trinity
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric Research, Education, and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
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11
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12
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Barrett-O'Keefe Z, Lee JF, Ives SJ, Trinity JD, Witman MAH, Rossman MJ, Groot HJ, Sorensen JR, Morgan DE, Nelson AD, Stehlik J, Richardson RS, Wray DW. α-Adrenergic receptor regulation of skeletal muscle blood flow during exercise in heart failure patients with reduced ejection fraction. Am J Physiol Regul Integr Comp Physiol 2019; 316:R512-R524. [PMID: 30789790 DOI: 10.1152/ajpregu.00345.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Patients suffering from heart failure with reduced ejection fraction (HFrEF) experience impaired limb blood flow during exercise, which may be due to a disease-related increase in α-adrenergic receptor vasoconstriction. Thus, in eight patients with HFrEF (63 ± 4 yr) and eight well-matched controls (63 ± 2 yr), we examined changes in leg blood flow (Doppler ultrasound) during intra-arterial infusion of phenylephrine (PE; an α1-adrenergic receptor agonist) and phentolamine (Phen; a nonspecific α-adrenergic receptor antagonist) at rest and during dynamic single-leg knee-extensor exercise (0, 5, and 10 W). At rest, the PE-induced reduction in blood flow was significantly attenuated in patients with HFrEF (-15 ± 7%) compared with controls (-36 ± 5%). During exercise, the controls exhibited a blunted reduction in blood flow induced by PE (-12 ± 4, -10 ± 4, and -9 ± 2% at 0, 5, and 10 W, respectively) compared with rest, while the PE-induced change in blood flow was unchanged compared with rest in the HFrEF group (-8 ± 5, -10 ± 3, and -14 ± 3%, respectively). Phen administration increased leg blood flow to a greater extent in the HFrEF group at rest (+178 ± 34% vs. +114 ± 28%, HFrEF vs. control) and during exercise (36 ± 6, 37 ± 7, and 39 ± 6% vs. 13 ± 3, 14 ± 1, and 8 ± 3% at 0, 5, and 10 W, respectively, in HFrEF vs. control). Together, these findings imply that a HFrEF-related increase in α-adrenergic vasoconstriction restrains exercising skeletal muscle blood flow, potentially contributing to diminished exercise capacity in this population.
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Affiliation(s)
| | - Joshua F Lee
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah
| | - Stephen J Ives
- Department of Exercise and Sport Science, University of Utah , Salt Lake City, Utah
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Melissa A H Witman
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Kinesiology and Applied Physiology, University of Delaware , Newark, Delaware
| | - Matthew J Rossman
- Department of Exercise and Sport Science, University of Utah , Salt Lake City, Utah
| | - H Jon Groot
- Department of Exercise and Sport Science, University of Utah , Salt Lake City, Utah
| | - Jacob R Sorensen
- Department of Exercise and Sport Science, University of Utah , Salt Lake City, Utah
| | - David E Morgan
- Department of Anesthesiology, University of Utah , Salt Lake City, Utah
| | - Ashley D Nelson
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Josef Stehlik
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - D Walter Wray
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
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13
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Park SK, La Salle DT, Cerbie J, Cho JM, Bledsoe A, Nelson A, Morgan DE, Richardson RS, Shiu YT, Boudina S, Trinity JD, Symons JD. Elevated arterial shear rate increases indexes of endothelial cell autophagy and nitric oxide synthase activation in humans. Am J Physiol Heart Circ Physiol 2019; 316:H106-H112. [PMID: 30412436 PMCID: PMC6734082 DOI: 10.1152/ajpheart.00561.2018] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 10/09/2018] [Accepted: 10/22/2018] [Indexed: 11/22/2022]
Abstract
Continuous laminar shear stress increases the process of autophagy, activates endothelial nitric oxide (NO) synthase phosphorylation at serine 1177 (p-eNOSS1177), and generates NO in bovine and human arterial endothelial cells (ECs) compared with static controls. However, the translational relevance of these findings has not been explored. In the current study, primary ECs were collected from the radial artery of 7 men using sterile J-wires before (Pre) and after (Post) 60 min of rhythmic handgrip exercise (HG) performed with the same arm. After ECs were identified by positive costaining for vascular endothelial cadherin and 4',6'-diamidino-2-phenylindole, immunofluorescent antibodies were used to assess indices of autophagy, NO generation, and superoxide anion (O2·-) production. Commercially available primary human arterial ECs were stained and processed in parallel to serve as controls. All end points were evaluated using 75 ECs from each subject. Relative to Pre-HG, HG elevated arterial shear rate ( P < 0.05) ~3-fold, whereas heart rate, arterial pressure, and cardiac output were not altered. Compared with values obtained from ECs Pre-HG, Post-HG ECs displayed increased ( P < 0.05) expression of p-eNOSS1177, NO generation, O2·- production, BECLIN1, microtubule-associated proteins 1A/1B light chain 3B, autophagy-related gene 3, and lysosomal-associated membrane protein 2A and decreased ( P < 0.05) expression (i.e., enhanced degradation) of the adaptor protein p62/sequestosome-1. These novel findings provide evidence that elevated arterial shear rate associated with functional hyperemia initiates autophagy, activates p-eNOSS1177, and increases NO and O2·- generation in primary human ECs. NEW & NOTEWORTHY Previously, our group reported in bovine arterial and human arterial endothelial cells (ECs) that shear stress initiates trafficking of the autophagosome to the lysosome and increases endothelial nitric oxide (NO) synthase phosphorylation at serine 1177, NO generation, and O2·- production. Here, the translational relevance of these findings is documented. Specifically, functional hyperemia induced by rhythmic handgrip exercise elevates arterial shear rate to an extent that increases indices of autophagy, NO generation, and O2·- production in primary arterial ECs collected from healthy men.
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Affiliation(s)
- Seul-Ki Park
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - D Taylor La Salle
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, and Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - James Cerbie
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, and Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Jae Min Cho
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Amber Bledsoe
- Department of Anesthesiology, University of Utah , Salt Lake City, Utah
| | - Ashley Nelson
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, and Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - David E Morgan
- Department of Anesthesiology, University of Utah , Salt Lake City, Utah
| | - Russell S Richardson
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, and Department of Internal Medicine, University of Utah , Salt Lake City, Utah
- Division of Geriatrics, Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Yan-Ting Shiu
- Division of Nephrology and Hypertension, Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Sihem Boudina
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
- Division of Endocrinology, Metabolism, and Diabetes, and Molecular Medicine Program, University of Utah School of Medicine , Salt Lake City, Utah
| | - Joel D Trinity
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, and Department of Internal Medicine, University of Utah , Salt Lake City, Utah
- Division of Geriatrics, Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - J David Symons
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
- Division of Endocrinology, Metabolism, and Diabetes, and Molecular Medicine Program, University of Utah School of Medicine , Salt Lake City, Utah
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14
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McNamara MM, Thomas JV, Alexander LF, Little MD, Bolus DN, Li YE, Morgan DE. Diffusion-weighted MRI as a screening tool for hepatocellular carcinoma in cirrhotic livers: correlation with explant data-a pilot study. Abdom Radiol (NY) 2018; 43:2686-2692. [PMID: 29500648 DOI: 10.1007/s00261-018-1535-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE The purpose of this study was to compare the sensitivity and specificity of diffusion-weighted liver MRI alone with complete, multiphasic gadoteridol-enhanced MRI for the detection of hepatocellular carcinoma in cirrhotic patients before liver transplant. MATERIALS AND METHODS This single institution retrospective study was performed after IRB approval and was HIPAA compliant. MRI scans of 37 patients who underwent liver transplant were evaluated and findings correlated with liver explant (36) or biopsy (1). All MRI scans were obtained within six months of explant. MRI from 17 patients with liver lesions by report at imaging subsequently proven to be HCC at pathology and 20 controls without liver lesions by imaging and pathology were reviewed in random order on the radiology PACS by three independent readers blinded to the MRI reports and pathology reports in two separate sittings. First, only the diffusion-weighted images (DWI) were interpreted. Second, the complete multiphasic MRI exam with DWI was reviewed. A consensus read was obtained by two separate radiologists who had access to the patients' explant data in order to map lesions. Reader-specific and pooled classification was assessed using sensitivity, specificity, positive predictive value, and negative predictive values and corresponding 95% confidence intervals (CI) for both DWI and complete MRI examination readings compared to pathology. McNemar's test and Kappa coefficient were used to assess differences (agreement) in DWI and complete examination readings. RESULTS A total of 37 patients have been studied (25M 12F age range 21-70). Averaged results of the three independent readers demonstrated a sensitivity of 78% (95% CI 65-89%) and specificity of 88% (95% CI 77-95%) for DWI alone for detection of liver lesions, with a positive predictive value of 85% (95% CI 72-94%) and a negative predictive value of 83% (95% CI 71-91%). Review of the complete MRI exam showed a sensitivity of 90% (95% CI 76-97%) and a specificity of 82% (95% CI 66-92%) with a positive predictive value of 83% (95% CI 69-93%) and a negative predictive value of 89% (95% CI 74-97%). McNemar's agreement test revealed no significant difference between the DWI and complete multiphasic interpretations (p = 0.3458), with simple Kappa coefficient of 0.6716 (95% CI 0.5332-0.8110). Lesions identified on DWI ranged in size from 1.5 to 5 cm. Detection of lesions was decreased in the presence of artifact from motion, large ascites, and technical issues. CONCLUSION Diffusion-weighted MRI has NPV and PPV comparable to complete multiphasic MRI examination for liver lesion detection in cirrhotic patients and may have a role in screening.
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Affiliation(s)
- M M McNamara
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - J V Thomas
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - L F Alexander
- Department of Radiology, Mayo Clinic Florida, Jacksonville, FL, USA
| | - M D Little
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - D N Bolus
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Yufeng E Li
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - D E Morgan
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
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15
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Broxterman RM, Hureau TJ, Layec G, Morgan DE, Bledsoe AD, Jessop JE, Amann M, Richardson RS. Influence of group III/IV muscle afferents on small muscle mass exercise performance: a bioenergetics perspective. J Physiol 2018; 596:2301-2314. [PMID: 29644702 DOI: 10.1113/jp275817] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/28/2018] [Indexed: 12/19/2022] Open
Abstract
KEY POINTS This investigation assessed the influence of group III/IV muscle afferents on small muscle mass exercise performance from a skeletal muscle bioenergetics perspective. Group III/IV muscle afferent feedback was attenuated with lumbar intrathecal fentanyl during intermittent isometric single-leg knee-extensor all-out exercise, while 31 P-MRS was used to assess skeletal muscle bioenergetics. Attenuation of group III/IV muscle afferent feedback improved exercise performance during the first minute of exercise, due to an increase in total ATP production with no change in the ATP cost of contraction. However, exercise performance was not altered during the remainder of the protocol, despite a sustained increase in total ATP production, due to an exacerbated ATP cost of contraction. These findings reveal that group III/IV muscle afferents directly limit exercise performance during small muscle mass exercise, but, due to their critical role in maintaining skeletal muscle contractile efficiency, with time, the benefit of attenuating the muscle afferents is negated. ABSTRACT The direct influence of group III/IV muscle afferents on exercise performance remains equivocal. Therefore, all-out intermittent isometric single-leg knee-extensor exercise and phosphorous magnetic resonance spectroscopy (31 P-MRS) were utilized to provide a high time resolution assessment of exercise performance and skeletal muscle bioenergetics in control conditions (CTRL) and with the attenuation of group III/IV muscle afferent feedback via lumbar intrathecal fentanyl (FENT). In both conditions, seven recreationally active men performed 60 maximal voluntary quadriceps contractions (MVC; 3 s contraction, 2 s relaxation), while knee-extensor force and 31 P-MRS were assessed during each MVC. The cumulative integrated force was significantly greater (8 ± 6%) in FENT than CTRL for the first minute of the all-out protocol, but was not significantly different for the second to fifth minutes. Total ATP production was significantly greater (16 ± 21%) in FENT than CTRL throughout the all-out exercise protocol, due to a significantly greater anaerobic ATP production (11 ± 13%) in FENT than CTRL with no significant difference in oxidative ATP production. The ATP cost of contraction was not significantly different between FENT and CTRL for the first minute of the all-out protocol, but was significantly greater (29 ± 34%) in FENT than in CTRL for the second to fifth minutes. These findings reveal that group III/IV muscle afferents directly limit exercise performance during small muscle mass exercise, but, due to their critical role in maintaining skeletal muscle contractile efficiency, with time, the benefit from muscle afferent attenuation is negated.
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Affiliation(s)
- Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Thomas J Hureau
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Gwenael Layec
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA.,Center on Aging, University of Utah, Salt Lake City, UT, USA
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Markus Amann
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA.,Center on Aging, University of Utah, Salt Lake City, UT, USA.,Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA.,Center on Aging, University of Utah, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
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16
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Park SK, La Salle DT, Cerbie J, Cho JM, Nelson A, Morgan DE, Trinity JD, Symons JD. Abstract 010: Similar Increases in Arterial Shear-rate Evoked by Handgrip Exercise Activate Autophagy and Enos to a Lesser Extent in Primary Endothelial Cells From Older vs. Adult Subjects. Arterioscler Thromb Vasc Biol 2018. [DOI: 10.1161/atvb.38.suppl_1.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We reported that genetic or pharmacological suppression of autophagy in bovine and human arterial endothelial cells (ECs) prevents shear-stress induced p-eNOS
S1177
and NO generation (Bharath et al.,
Arterioscler Thromb Vasc Biol
, 2017). To date, one human study indicates an aging-associated repression of EC autophagy is concurrent with arterial dysfunction (LaRocca et al.,
J Physiol
, 2012). We tested the hypothesis that a physiological elevation of arterial shear-rate activates autophagy and p-eNOS
S1177
to a lesser extent in primary ECs from older vs. adult participants. After familiarization with laboratory procedures, flow-mediated vasodilation (%FMD) was observed to be lower (p<0.05) in 4 older (68±5 yr; 3.9±1.3 %) vs. 5 adult (23±3 yr; 7.9±1.1 %) male subjects. Within 1-week, a catheter was placed into the radial artery (RA). ECs were collected 30-min later via j-wire from the RA. Next, subjects performed rhythmic handgrip exercise (RHE) for 60-min that elevated (p<0.05) arterial shear-rate similarly (2.6 ± 0.2-fold) between groups from pre-exercise values. Shear-rate [8V
mean
/brachial artery (BA) diameter] was obtained by assessing BA diameter, BA blood flow velocity (V
mean
), and BA blood flow [(V
mean
π (vessel diameter / 2)
2
x 60)] at 5-10 min intervals using Doppler ultrasound. Compared to pre-exercise values, RHE did not alter heart rate, stroke volume, cardiac output, or arterial pressure (plethysmography) in either group. Immediately following RHE ECs were collected from the RA. Using quantitative immunofluorescence, primary ECs (75 ECs per endpoint per subject) were identified by positive co-staining for VE-cadherin and DAPI via confocal microscopy. Immortalized human arterial ECs processed and stained in parallel served as fluorescence intensity controls. Relative to pre-exercise, ECs from adult but not old subjects at 60-min displayed increased expression of microtubule associated protein light chain 3 (p<0.04), lysosomal associated membrane protein 2a (p<0.01), autophagy-related gene 3 (p=0.06), and p-eNOS
S1177
(p<0.02), and decreased expression of the adaptor protein p62 (p<0.02). These data indicate aging limits shear-induced EC autophagy and eNOS activation in response to functional hyperemia.
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17
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Trinity JD, Broxterman RM, Gifford JR, Kwon OS, Hydren JR, Kithas AC, Nelson AD, Morgan DE, Jessop JE, Bledsoe A, Richardson RS. Mechanisms of Age‐related Compensatory Vasodilation: Insight from Passive Leg Movement. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.726.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Joel D. Trinity
- Geriatric ResearchEducation and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSaltUT
- Internal MedicinceUniversity of UtahSaltUT
| | - Ryan M. Broxterman
- Geriatric ResearchEducation and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | - Jayson R. Gifford
- Geriatric ResearchEducation and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
| | | | - Jay R. Hydren
- Nutrition and Integrative PhysiologyUniversity of UtahSaltUT
| | | | | | | | | | | | - Russell S. Richardson
- Geriatric ResearchEducation and Clinical CenterSalt Lake City VAMCSalt Lake CityUT
- Nutrition and Integrative PhysiologyUniversity of UtahSaltUT
- Internal MedicinceUniversity of UtahSaltUT
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18
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Bunsawat K, Ratchford SM, Clifton HL, Theisen JK, Barrett‐O'Keefe Z, Broxterman RM, Gifford JR, Hydren J, Rossman MJ, Ives SJ, Trinity JD, Witman MA, Garten RS, Morgan DE, Nelson AD, Richardson RS, Wray DW. Sex Differences in the Sympathetic Restraint of Skeletal Muscle Blood Flow in the Human Leg Vasculature. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.594.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Kanokwan Bunsawat
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
| | - Stephen M. Ratchford
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
| | - Heather L. Clifton
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
| | - Jeremy K. Theisen
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | | | - Ryan M. Broxterman
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
| | - Jayson R. Gifford
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
- Department of Exercise SciencesBrigham Young UniversityProvoUT
| | - Jay Hydren
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Matthew J. Rossman
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Stephen J. Ives
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
| | - Joel D. Trinity
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- University of Utah Center on AgingSalt Lake CityUT
| | - Melissa A.H. Witman
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
- Department of Kinesiology and Applied PhysiologyUniversity of DelawareNewarkDE
| | - Ryan S. Garten
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - David E. Morgan
- Department of AnesthesiologyUniversity of UtahSalt Lake CityUT
| | - Ashley D. Nelson
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
| | - Russell S. Richardson
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- University of Utah Center on AgingSalt Lake CityUT
| | - D. Walter Wray
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineDivision of GeriatricsUniversity of UtahSalt Lake CityUT
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- University of Utah Center on AgingSalt Lake CityUT
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Park S, LaSalle DT, Cerbie J, Cho JM, Nelson A, Morgan DE, Trinity JD, Symons JD. Rhythmic handgrip exercise elevates arterial shear‐rate and increases indices of endothelial cell autophagy and nitric oxide synthase activation in humans. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.902.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Seul‐Ki Park
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Division of Endocrinology, Metabolism and Diabetes and Program in Molecular MedicineUniversity of UtahSalt Lake CityUT
| | - D Taylor LaSalle
- Geriatric ResearchEducation and Clinical CenterUniversity of UtahSalt Lake CityUT
| | - James Cerbie
- Geriatric ResearchEducation and Clinical CenterUniversity of UtahSalt Lake CityUT
| | - Jae Min Cho
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Division of Endocrinology, Metabolism and Diabetes and Program in Molecular MedicineUniversity of UtahSalt Lake CityUT
| | - Ashely Nelson
- Geriatric ResearchEducation and Clinical CenterUniversity of UtahSalt Lake CityUT
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - David E. Morgan
- Geriatric ResearchEducation and Clinical CenterUniversity of UtahSalt Lake CityUT
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Joel D. Trinity
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Geriatric ResearchEducation and Clinical CenterUniversity of UtahSalt Lake CityUT
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - J David Symons
- Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Division of Endocrinology, Metabolism and Diabetes and Program in Molecular MedicineUniversity of UtahSalt Lake CityUT
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Theisen JL, Ratchford SM, Clifton HL, Bunsawat K, Barret‐O'keefe Z, Broxterman RM, Gifford JR, Hydren J, Rossman MJ, Ives SJ, Witman MA, Trinity JD, Garten RJ, Morgan DE, Nelson AD, Richardson RS, Wray DW. Role of Alpha‐1 Adrenergic Vasoconstriction in Regulating Skeletal Muscle Blood Flow during Single Leg Knee Extension Exercise with Advancing Age. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.594.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jeremy L. Theisen
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Stephen M. Ratchford
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | | | - Kanokwan Bunsawat
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | | | - Ryan M. Broxterman
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Jayson R. Gifford
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- Department of Exercise SciencesBrigham Young UniversityProvoUT
| | - Jay Hydren
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Matthew J. Rossman
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - Steve J. Ives
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Melissa A.H. Witman
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- Department of Applied KinesiologyUniversity of DelawareNewarkDE
| | - Joel D. Trinity
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- University of Utah Center on AgingSalt Lake CityUT
| | - Ryan J. Garten
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
| | - David E. Morgan
- Department of AnesthesiologyUniversity of UtahSalt Lake CityUT
| | - Ashley D. Nelson
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
| | - Russel S. Richardson
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- University of Utah Center on AgingSalt Lake CityUT
| | - D Walter Wray
- Geriatric Research, Educationand Clinical CenterVAMCSalt Lake CityUT
- Department of Nutrition and Integrative PhysiologyUniversity of UtahSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
- University of Utah Center on AgingSalt Lake CityUT
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21
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Broxterman RM, Layec G, Hureau TJ, Morgan DE, Bledsoe AD, Jessop JE, Amann M, Richardson RS. Bioenergetics and ATP Synthesis during Exercise: Role of Group III/IV Muscle Afferents. Med Sci Sports Exerc 2018; 49:2404-2413. [PMID: 28767527 DOI: 10.1249/mss.0000000000001391] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE The purpose of this study was to investigate the role of the group III/IV muscle afferents in the bioenergetics of exercising skeletal muscle beyond constraining the magnitude of metabolic perturbation. METHODS Eight healthy men performed intermittent isometric knee-extensor exercise to task failure at ~58% maximal voluntary contraction under control conditions (CTRL) and with lumbar intrathecal fentanyl to attenuate group III/IV leg muscle afferents (FENT). Intramuscular concentrations of phosphocreatine (PCr), inorganic phosphate (Pi), diprotonated phosphate (H2PO4), adenosine triphosphate (ATP), and pH were determined using phosphorous magnetic resonance spectroscopy (P-MRS). RESULTS The magnitude of metabolic perturbation was significantly greater in FENT compared with CTRL for [Pi] (37.8 ± 16.8 vs 28.6 ± 8.6 mM), [H2PO4] (24.3 ± 12.2 vs 17.9 ± 7.1 mM), and [ATP] (75.8% ± 17.5% vs 81.9% ± 15.8% of baseline), whereas there was no significant difference in [PCr] (4.5 ± 2.4 vs 4.4 ± 2.3 mM) or pH (6.51 ± 0.10 vs 6.54 ± 0.14). The rate of perturbation in [PCr], [Pi], [H2PO4], and pH was significantly faster in FENT compared with CTRL. Oxidative ATP synthesis was not significantly different between conditions. However, anaerobic ATP synthesis, through augmented creatine kinase and glycolysis reactions, was significantly greater in FENT than in CTRL, resulting in a significantly greater ATP cost of contraction (0.049 ± 0.016 vs 0.038 ± 0.010 mM·min·N). CONCLUSION Group III/IV muscle afferents not only constrain the magnitude of perturbation in intramuscular Pi, H2PO4, and ATP during small muscle mass exercise but also seem to play a role in maintaining efficient skeletal muscle contractile function in men.
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Affiliation(s)
- Ryan M Broxterman
- 1Geriatric Research, Education, and Clinical Center, Salt Lake City Veteran's Affairs Medical Center, Salt Lake City, UT; 2Department of Internal Medicine, University of Utah, Salt Lake City, UT; 3Department of Anesthesiology, University of Utah, Salt Lake City, UT; and 4Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
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Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Kithas AC, Hydren JR, Nelson AD, Morgan DE, Jessop JE, Bledsoe AD, Richardson RS. Single passive leg movement assessment of vascular function: contribution of nitric oxide. J Appl Physiol (1985) 2017; 123:1468-1476. [PMID: 28860173 DOI: 10.1152/japplphysiol.00533.2017] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Kithas AC, Hydren JR, Nelson AD, Morgan DE, Jessop JE, Bledsoe AD, Richardson RS. Single passive leg movement assessment of vascular function: contribution of nitric oxide. J Appl Physiol 123: 1468-1476, 2017. First published August 31, 2017; doi:10.1152/japplphysiol.00533.2017.-The assessment of passive leg movement (PLM)-induced leg blood flow (LBF) and vascular conductance (LVC) is a novel approach to assess vascular function that has recently been simplified to only a single PLM (sPLM), thereby increasing the clinical utility of this technique. As the physiological mechanisms mediating the robust increase in LBF and LVC with sPLM are unknown, we tested the hypothesis that nitric oxide (NO) is a major contributor to the sPLM-induced LBF and LVC response. In nine healthy men, sPLM was performed with and without NO synthase inhibition by intra-arterial infusion of NG-monomethyl-l-arginine (l-NMMA). Doppler ultrasound and femoral arterial pressure were used to determine LBF and LVC, which were characterized by the peak change (ΔLBFpeak and ΔLVCpeak) and area under the curve (LBFAUC and LVCAUC). l-NMMA significantly attenuated ΔLBFpeak [492 ± 153 (l-NMMA) vs. 719 ± 238 (control) ml/min], LBFAUC [57 ± 34 (l NMMA) vs. 147 ± 63 (control) ml], ΔLVCpeak [4.7 ± 1.1 (l-NMMA) vs. 8.0 ± 3.0 (control) ml·min-1·mmHg-1], and LVCAUC [0.5 ± 0.3 (l-NMMA) vs. 1.6 ± 0.9 (control) ml/mmHg]. The magnitude of the NO contribution to LBF and LVC was significantly correlated with the magnitude of the control responses ( r = 0.94 for ΔLBFpeak, r = 0.85 for LBFAUC, r = 0.94 for ΔLVCpeak, and r = 0.95 for LVCAUC). These data establish that the sPLM-induced hyperemic and vasodilatory response is predominantly (~65%) NO-mediated. As such, sPLM appears to be a promising, simple, in vivo assessment of NO-mediated vascular function and NO bioavailability. NEW & NOTEWORTHY Passive leg movement (PLM), a novel assessment of vascular function, has been simplified to a single PLM (sPLM), thereby increasing the clinical utility of this technique. However, the role of nitric oxide (NO) in mediating the robust sPLM hemodynamic responses is unknown. This study revealed that sPLM induces a hyperemic and vasodilatory response that is predominantly NO-mediated and, as such, appears to be a promising simple, in vivo, clinical assessment of NO-mediated vascular function and, therefore, NO bioavailability.
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Affiliation(s)
- Ryan M Broxterman
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Oh Sung Kwon
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Andrew C Kithas
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - Jay R Hydren
- Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Ashley D Nelson
- Department of Internal Medicine, University of Utah , Salt Lake City, Utah
| | - David E Morgan
- Department of Anesthesiology, University of Utah , Salt Lake City, Utah
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah , Salt Lake City, Utah
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah , Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Internal Medicine, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
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Broxterman RM, Layec G, Hureau TJ, Morgan DE, Bledsoe AD, Jessop JE, Amann M, Richardson RS. Skeletal Muscle Force Production and Bioenergetics During All-out Exercise. Med Sci Sports Exerc 2017. [DOI: 10.1249/01.mss.0000519454.23113.c3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Kithas AC, Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Hydren JR, Nelson AD, Jessop JE, Bledsoe AD, Morgan DE, Richardson RS. Determining The Window Of Effect In The Human Vasculature For The Nitric Oxide Synthase Inhibitor N(G)-monomethyl-L-arginine (L-NMMA). Med Sci Sports Exerc 2017. [DOI: 10.1249/01.mss.0000519224.07620.d2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Griffee MJ, Singleton A, Zimmerman JM, Morgan DE, Nirula R. The Effect of Perioperative Rescue Transesophageal Echocardiography on the Management of Trauma Patients. ACTA ACUST UNITED AC 2017; 6:387-90. [PMID: 27301053 DOI: 10.1213/xaa.0000000000000320] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To evaluate the effect of rescue transesophageal echocardiography (TEE) on the management of trauma patients, we reviewed imaging and charts of unstable trauma patients at a level I trauma center. Critical rescue TEE findings included acute right ventricular failure, stress cardiomyopathy, type B aortic dissection, mediastinal air, and dynamic left ventricular outflow tract obstruction. Left ventricular filling was classified as low (underfilled) in 57% of all cases. Rescue TEE revealed a variety of new diagnoses and led to a change in resuscitation strategy about half of the time.
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Affiliation(s)
- Matthew J Griffee
- From the *Department of Anesthesiology, University of Utah, Salt Lake City, Utah; †Department of Surgery, University of Southern California, Los Angeles, California; and ‡Department of Surgery, University of Utah, Salt Lake City, Utah
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26
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Ives SJ, Amann M, Venturelli M, Witman MAH, Groot HJ, Wray DW, Morgan DE, Stehlik J, Richardson RS. The Mechanoreflex and Hemodynamic Response to Passive Leg Movement in Heart Failure. Med Sci Sports Exerc 2017; 48:368-76. [PMID: 26418560 DOI: 10.1249/mss.0000000000000782] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND Sensitization of mechanosensitive afferents, which contribute to the exercise pressor reflex, has been recognized as a characteristic of patients with heart failure (HF); however, the hemodynamic implications of this hypersensitivity are unclear. OBJECTIVES The present study used passive leg movement (PLM) and intrathecal injection of fentanyl to blunt the afferent portion of this reflex arc to better understand the role of the mechanoreflex on central and peripheral hemodynamics in HF. METHODS Femoral blood flow (FBF), mean arterial pressure, femoral vascular conductance, HR, stroke volume, cardiac output, ventilation, and muscle oxygenation of the vastus lateralis were assessed in 10 patients with New York Heart Association class II HF at baseline and during 3 min of PLM both with fentanyl and without (control). RESULTS Fentanyl had no effect on baseline measures but increased (control vs fentanyl, P < 0.05) the peak PLM-induced change in FBF (493 ± 155 vs 804 ± 198 ΔmL·min(-1)) and femoral vascular conductance (4.7 ± 2 vs 8.5 ± 3 ΔmL·min(-1)·mm Hg)(-1) while norepinephrine spillover (103% ± 19% vs 58% ± 17%Δ) and retrograde FBF (371 ± 115 vs 260 ± 68 ΔmL·min(-1)) tended to be reduced (P < 0.10). In addition, fentanyl administration resulted in greater PLM-induced increases in muscle oxygenation, suggestive of increased microvascular perfusion. Fentanyl had no effect on the ventilation, mean arterial pressure, HR, stroke volume, or cardiac output response to PLM. CONCLUSIONS Although movement-induced central hemodynamics were unchanged by afferent blockade, peripheral hemodynamic responses were significantly enhanced. Thus, in patients with HF, a heightened mechanoreflex seems to augment peripheral sympathetic vasoconstriction in response to movement, a phenomenon that may contribute to exercise intolerance in this population.
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Affiliation(s)
- Stephen J Ives
- 1Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veteran Affairs Medical Center, Salt Lake City, UT; 2Department of Internal Medicine, University of Utah, Salt Lake City, UT; 3Health and Exercise Sciences Department, Skidmore College, Saratoga Springs, NY; 4Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT; 5Department of Biomedical Sciences for Health, University of Milan, Milan, ITALY; 6Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE; and 7Department of Anesthesiology, University of Utah, Salt Lake City, UT
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Abstract
The collapse of communism and the Cold War have precipitated a broad reconsideration of central principles of democracy and societal governance. This paper examines a recent contribution by Paul Hirst—a model of associ ative democracy. Drawing on principles of associationalism and rational choice, Hirst sets out a model of participatory democracy, which focuses on general principles, economic institutions and welfare provisions. Mandatory economic democracy and a bifurcated structure of political governance are proposed. Voluntary associations are presented as primary vehicles of communicative democracy and social life. It is argued that Hirst's formulations of rational choice and the decentralisation of the state are fundamentally untenable: he proposes regulation of economic relations to secure socially responsible outcomes, and the injection of market relations into state administration to maximise individual choice. It is concluded that Hirst's theoretical tools are incompatible with the nature of political governance advocated. Moreover, the fracturing of state power, in search of dubious advantages of decentralised associations, undermines the positive gains of universal state action.
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Affiliation(s)
- David E. Morgan
- School of Industrial Relations and Organisational Behaviour University of New South Wales
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29
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Gifford JR, Garten RS, Nelson AD, Trinity JD, Layec G, Witman MAH, Weavil JC, Mangum T, Hart C, Etheredge C, Jessop J, Bledsoe A, Morgan DE, Wray DW, Rossman MJ, Richardson RS. Symmorphosis and skeletal muscle V̇O2 max : in vivo and in vitro measures reveal differing constraints in the exercise-trained and untrained human. J Physiol 2016; 594:1741-51. [PMID: 26614395 DOI: 10.1113/jp271229] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 11/10/2015] [Indexed: 01/15/2023] Open
Abstract
The concept of symmorphosis postulates a matching of structural capacity to functional demand within a defined physiological system, regardless of endurance exercise training status. Whether this concept applies to oxygen (O2 ) supply and demand during maximal skeletal muscle O2 consumption (V̇O2 max ) in humans is unclear. Therefore, in vitro skeletal muscle mitochondrial V̇O2 max (Mito V̇O2 max , mitochondrial respiration of fibres biopsied from vastus lateralis) was compared with in vivo skeletal muscle V̇O2 max during single leg knee extensor exercise (KE V̇O2 max , direct Fick by femoral arterial and venous blood samples and Doppler ultrasound blood flow measurements) and whole-body V̇O2 max during cycling (Body V̇O2 max , indirect calorimetry) in 10 endurance exercise-trained and 10 untrained young males. In untrained subjects, during KE exercise, maximal O2 supply (KE Q̇O2max ) exceeded (462 ± 37 ml kg(-1) min(-1) , P < 0.05) and KE V̇O2 max matched (340 ± 22 ml kg(-1) min(-1) , P > 0.05) Mito V̇O2 max (364 ± 16 ml kg(-1) min(-1) ). Conversely, in trained subjects, both KE Q̇O2max (557 ± 35 ml kg(-1) min(-1) ) and KE V̇O2 max (458 ± 24 ml kg(-1) min(-1) ) fell far short of Mito V̇O2 max (743 ± 35 ml kg(-1) min(-1) , P < 0.05). Although Mito V̇O2 max was related to KE V̇O2 max (r = 0.69, P < 0.05) and Body V̇O2 max (r = 0.91, P < 0.05) in untrained subjects, these variables were entirely unrelated in trained subjects. Therefore, in untrained subjects, V̇O2 max is limited by mitochondrial O2 demand, with evidence of adequate O2 supply, whereas, in trained subjects, an exercise training-induced mitochondrial reserve results in skeletal muscle V̇O2 max being markedly limited by O2 supply. Taken together, these in vivo and in vitro measures reveal clearly differing limitations and excesses at V̇O2 max in untrained and trained humans and challenge the concept of symmorphosis as it applies to O2 supply and demand in humans.
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Affiliation(s)
- Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Ryan S Garten
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Ashley D Nelson
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Gwenael Layec
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Melissa A H Witman
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Joshua C Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Tyler Mangum
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Corey Hart
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Cory Etheredge
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Jake Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Amber Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - D Walter Wray
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Matthew J Rossman
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
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30
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Groot HJ, Trinity JD, Layec G, Rossman MJ, Ives SJ, Morgan DE, Bledsoe A, Richardson RS. The role of nitric oxide in passive leg movement-induced vasodilatation with age: insight from alterations in femoral perfusion pressure. J Physiol 2015; 593:3917-28. [PMID: 26108562 DOI: 10.1113/jp270195] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 06/09/2015] [Indexed: 11/08/2022] Open
Abstract
The passive leg movement (PLM) model is a novel approach to assess vascular function. Increasing femoral perfusion pressure (FPP) by moving from the supine to the upright-seated posture augments the vasodilatory response to PLM in the young, with no effect in the old, but whether this augmented vasodilatation is nitric oxide (NO) dependent is unknown. Using an intra-arterial infusion of N(G) -monomethyl-L -arginine (L -NMMA) to inhibit nitric oxide synthase (NOS), the posture-induced increases in the PLM responses in the young were nearly ablated, with no effect of NOS inhibition in the old. Therefore, PLM in combination with alterations in posture can be used to determine changes in NO-mediated vasodilatation with age, and thus, may be a clinically useful tool for assessing NO bioavailability across the human lifespan. We sought to better understand the contribution of nitric oxide (NO) to passive leg movement (PLM)-induced vasodilatation with age, with and without a posture-induced increase in femoral perfusion pressure (FPP). PLM was performed in eight young (24 ± 1 years) and eight old (74 ± 3 years) healthy males, with and without NO synthase inhibition via intra-arterial infusion of N(G) -monomethyl-L -arginine (L -NMMA) into the common femoral artery in both the supine and upright-seated posture. Central and peripheral haemodynamic responses were determined second-by-second with finger photoplethysmography and Doppler ultrasound, respectively. PLM-induced increases in heart rate, stroke volume, cardiac output and reductions in mean arterial pressure were similar between age groups and conditions. In the young, L -NMMA attenuated the peak change in leg vascular conductance (ΔLVCpeak ) in both the supine (control: 7.4 ± 0.9; L -NMMA: 5.2 ± 1.1 ml min(-1) mmHg(-1) , P < 0.05) and upright-seated (control: 12.3 ± 2.0; L -NMMA: 6.4 ± 1.0 ml min(-1) mmHg(-1) , P < 0.05) posture, with no significant change in the old (supine control: 4.2 ± 1.3; supine L -NMMA: 3.4 ± 0.8; upright-seated control: 4.5 ± 0.8; upright-seated L -NMMA: 3.4 ± 0.8 ml min(-1) mmHg(-1) , P > 0.05). Increased FPP augmented the ΔLVCpeak in the young control condition only (P < 0.05). In the upright-seated posture, NOS inhibition attenuated the FPP-induced augmentation of rapid vasodilatation in the young (control: 1.25 ± 0.23; L -NMMA: 0.74 ± 0.11 ml min(-1) mmHg(-1) s(-1) ; P < 0.05), but not the old (control: 0.37 ± 0.07; L -NMMA: 0.25 ± 0.07 ml ml min(-1) mmHg(-1) s(-1) ; P > 0.05). These data reveal that greater FPP increases the role of NO in PLM-induced vasodilatation in the young, but not the old, due to reduced NO bioavailability with age. Therefore, PLM involving alterations in posture may be useful to determine changes in NO bioavailability with age.
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Affiliation(s)
- H Jonathan Groot
- Geriatric Research, Education, and Clinical Centre, VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Centre, VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Gwenael Layec
- Geriatric Research, Education, and Clinical Centre, VAMC, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Matthew J Rossman
- Geriatric Research, Education, and Clinical Centre, VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Stephen J Ives
- Health and Exercise Sciences Department, Skidmore College, Saratoga Springs, NY, USA
| | - David E Morgan
- Department of Anesthesia, University of Utah, Salt Lake City, UT, USA
| | - Amber Bledsoe
- Department of Anesthesia, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Centre, VAMC, Salt Lake City, UT, USA.,Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
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Rossman MJ, Trinity JD, Garten RS, Ives SJ, Conklin JD, Barrett-O'Keefe Z, Witman MAH, Bledsoe AD, Morgan DE, Runnels S, Reese VR, Zhao J, Amann M, Wray DW, Richardson RS. Oral antioxidants improve leg blood flow during exercise in patients with chronic obstructive pulmonary disease. Am J Physiol Heart Circ Physiol 2015; 309:H977-85. [PMID: 26188020 DOI: 10.1152/ajpheart.00184.2015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 07/10/2015] [Indexed: 11/22/2022]
Abstract
The consequence of elevated oxidative stress on exercising skeletal muscle blood flow as well as the transport and utilization of O2 in patients with chronic obstructive pulmonary disease (COPD) is not well understood. The present study examined the impact of an oral antioxidant cocktail (AOC) on leg blood flow (LBF) and O2 consumption during dynamic exercise in 16 patients with COPD and 16 healthy subjects. Subjects performed submaximal (3, 6, and 9 W) single-leg knee extensor exercise while LBF (Doppler ultrasound), mean arterial blood pressure, leg vascular conductance, arterial O2 saturation, leg arterial-venous O2 difference, and leg O2 consumption (direct Fick) were evaluated under control conditions and after AOC administration. AOC administration increased LBF (3 W: 1,604 ± 100 vs. 1,798 ± 128 ml/min, 6 W: 1,832 ± 109 vs. 1,992 ± 120 ml/min, and 9W: 2,035 ± 114 vs. 2,187 ± 136 ml/min, P < 0.05, control vs. AOC, respectively), leg vascular conductance, and leg O2 consumption (3 W: 173 ± 12 vs. 210 ± 15 ml O2/min, 6 W: 217 ± 14 vs. 237 ± 15 ml O2/min, and 9 W: 244 ± 16 vs 260 ± 18 ml O2/min, P < 0.05, control vs. AOC, respectively) during exercise in COPD, whereas no effect was observed in healthy subjects. In addition, the AOC afforded a small, but significant, improvement in arterial O2 saturation only in patients with COPD. Thus, these data demonstrate a novel beneficial role of AOC administration on exercising LBF, O2 consumption, and arterial O2 saturation in patients with COPD, implicating oxidative stress as a potential therapeutic target for impaired exercise capacity in this population.
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Affiliation(s)
- Matthew J Rossman
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Ryan S Garten
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Stephen J Ives
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, New York
| | - Jamie D Conklin
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, Department of Internal Medicine, University of Utah, Salt Lake City, Utah; and
| | - Zachary Barrett-O'Keefe
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Melissa A H Witman
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Sean Runnels
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Van R Reese
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Jia Zhao
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Markus Amann
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - D Walter Wray
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah; Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah;
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Trinity JD, Groot HJ, Layec G, Rossman MJ, Ives SJ, Morgan DE, Gmelch BS, Bledsoe A, Richardson RS. Passive leg movement and nitric oxide-mediated vascular function: the impact of age. Am J Physiol Heart Circ Physiol 2015; 308:H672-9. [PMID: 25576629 PMCID: PMC4360052 DOI: 10.1152/ajpheart.00806.2014] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 01/05/2015] [Indexed: 01/14/2023]
Abstract
In young healthy men, passive leg movement (PLM) elicits a robust nitric oxide (NO)-dependent increase in leg blood flow (LBF), thus providing a novel approach to assess NO-mediated vascular function. While the magnitude of the LBF response to PLM is markedly reduced with age, the role of NO in this attenuated response in the elderly is unknown. Therefore, this study sought to determine the contribution of NO in the PLM-induced LBF with age. Fourteen male subjects (7 young, 24 ± 1 yr; and 7 old, 75 ± 3 yr) underwent PLM with and without NO synthase (NOS) inhibition achieved by intra-arterial infusion of N(G)-monomethyl-L-arginine (L-NMMA). LBF was determined second-by-second by Doppler ultrasound, and central hemodynamics were measured by finger photoplethysmography. NOS inhibition blunted the PLM-induced peak increase in LBF in the young (control: 668 ± 106; L-NMMA 431 ± 95 Δml/min; P = 0.03) but had no effect in the old (control: 266 ± 98; L-NMMA 251 ± 92 Δml/min; P = 0.59). Likewise, the magnitude of the reduction in the overall (i.e., area under the curve) PLM-induced LBF response to NOS inhibition was less in the old (LBF: -31 ± 18 ml) than the young (LBF: -129 ± 21 ml; P < 0.01). These findings suggest that the age-associated reduction in PLM-induced LBF in the elderly is primarily due to a reduced contribution to vasodilation from NO and therefore support the use of PLM as a novel approach to assess NO-mediated vascular function across the lifespan.
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Affiliation(s)
- Joel D Trinity
- Geriatric Research Education and Clinical Center, George E. Wahlen, Veteran Affairs Medical Center, Salt Lake City, Utah; Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah;
| | - H Jonathan Groot
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Gwenael Layec
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah
| | - Matthew J Rossman
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
| | - Stephen J Ives
- Geriatric Research Education and Clinical Center, George E. Wahlen, Veteran Affairs Medical Center, Salt Lake City, Utah; Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah; Department of Health and Exercise Sciences, Skidmore College, Saratoga Springs, New York
| | - David E Morgan
- Department of Anesthesia, University of Utah, Salt Lake City, Utah; and
| | - Ben S Gmelch
- Department of Anesthesia, University of Utah, Salt Lake City, Utah; and
| | - Amber Bledsoe
- Department of Anesthesia, University of Utah, Salt Lake City, Utah; and
| | - Russell S Richardson
- Geriatric Research Education and Clinical Center, George E. Wahlen, Veteran Affairs Medical Center, Salt Lake City, Utah; Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, Utah; Department of Exercise and Sport Science, University of Utah, Salt Lake City, Utah
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Markin NW, Gmelch BS, Griffee MJ, Holmberg TJ, Morgan DE, Zimmerman JM. A Review of 364 Perioperative Rescue Echocardiograms: Findings of an Anesthesiologist-Staffed Perioperative Echocardiography Service. J Cardiothorac Vasc Anesth 2015; 29:82-8. [DOI: 10.1053/j.jvca.2014.07.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Indexed: 01/01/2023]
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Sidhu SK, Weavil JC, Venturelli M, Garten RS, Rossman MJ, Richardson RS, Gmelch BS, Morgan DE, Amann M. Spinal μ-opioid receptor-sensitive lower limb muscle afferents determine corticospinal responsiveness and promote central fatigue in upper limb muscle. J Physiol 2014; 592:5011-24. [PMID: 25172953 DOI: 10.1113/jphysiol.2014.275438] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We investigated the influence of group III/IV lower limb muscle afferents on the development of supraspinal fatigue and the responsiveness of corticospinal projections to an arm muscle. Eight males performed constant-load leg cycling exercise (80% peak power output) for 30 s (non-fatiguing) and to exhaustion (∼9 min; fatiguing) both under control conditions and with lumbar intrathecal fentanyl impairing feedback from μ-opioid receptor-sensitive lower limb muscle afferents. Voluntary activation (VA) of elbow flexors was assessed via transcranial magnetic stimulation (TMS) during maximum voluntary contraction (MVC) and corticospinal responsiveness was monitored via TMS-evoked potentials (MEPs) during a 25% MVC. Accompanied by a significant 5 ± 1% reduction in VA from pre- to post-exercise, elbow flexor MVC progressively decreased during the fatiguing trial (P < 0.05). By contrast, with attenuated feedback from locomotor muscle afferents, MVC and VA remained unchanged during fatiguing exercise (P > 0.3). MEPs decreased by 36 ± 6% (P < 0.05) from the start of exercise to exhaustion under control conditions, but this reduction was prevented with fentanyl blockade. Furthermore, fentanyl blockade prevented the significant increase in elbow flexor MEP observed from rest to non-fatiguing exercise under control conditions and resulted in a 14% lower corticospinal responsiveness during this short bout (P < 0.05). Taken together, in the absence of locomotor muscle fatigue, group III/IV-mediated leg muscle afferents facilitate responsiveness of the motor pathway to upper limb flexor muscles. By contrast, in the presence of cycling-induced leg fatigue, group III/IV locomotor muscle afferents facilitate supraspinal fatigue in remote muscle not involved in the exercise and disfacilitate, or inhibit, the responsiveness of corticospinal projections to upper limb muscles.
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Affiliation(s)
- Simranjit K Sidhu
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Joshua C Weavil
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Massimo Venturelli
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Ryan S Garten
- Geriatric Research, Education and Clinical Center, Veterans Affairs Medical Center (VAMC), Salt Lake City, UT, USA
| | - Matthew J Rossman
- Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA Geriatric Research, Education and Clinical Center, Veterans Affairs Medical Center (VAMC), Salt Lake City, UT, USA
| | - Benjamin S Gmelch
- Department of Anaesthesiology, University of Utah, Salt Lake City, UT, USA
| | - David E Morgan
- Department of Anaesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Markus Amann
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT, USA Geriatric Research, Education and Clinical Center, Veterans Affairs Medical Center (VAMC), Salt Lake City, UT, USA Department of Anaesthesiology, University of Utah, Salt Lake City, UT, USA
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Barrett-O'Keefe Z, Ives SJ, Trinity JD, Morgan G, Rossman MJ, Donato AJ, Runnels S, Morgan DE, Gmelch BS, Bledsoe AD, Richardson RS, Wray DW. Endothelin-A-mediated vasoconstriction during exercise with advancing age. J Gerontol A Biol Sci Med Sci 2014; 70:554-65. [PMID: 24821105 DOI: 10.1093/gerona/glu065] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 03/31/2014] [Indexed: 11/14/2022] Open
Abstract
The endothelin-1 vasoconstrictor pathway contributes to age-related elevations in resting peripheral vascular tone primarily through activation of the endothelin subtype A (ET(A)) receptor. However, the regulatory influence of ET(A)-mediated vasoconstriction during exercise in the elderly is unknown. Thus, in 17 healthy volunteers (n = 8 young, 24±2 years; n = 9 old, 70±2 years), we examined leg blood flow, mean arterial pressure, leg arterial-venous oxygen (O2) difference, and leg O2 consumption (VO2) at rest and during knee-extensor exercise before and after intra-arterial administration of the ET(A) antagonist BQ-123. During exercise, BQ-123 administration increased leg blood flow to a greater degree in the old (+29±5 mL/min/W) compared with the young (+16±3 mL/min/W). The increase in leg blood flow with BQ-123 was accompanied by an increase in leg VO2 in both groups, suggesting a reduced efficiency following ET(A) receptor blockade. Together, these findings have identified an age-related increase in ET(A)-mediated vasoconstrictor activity that persists during exercise, suggesting an important role of this pathway in the regulation of exercising skeletal muscle blood flow and maintenance of arterial blood pressure in the elderly.
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Affiliation(s)
- Zachary Barrett-O'Keefe
- Department of Exercise and Sport Science, University of Utah, Salt Lake City. Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah
| | - Stephen J Ives
- Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah. Department of Internal Medicine, University of Utah, Salt Lake City
| | - Joel D Trinity
- Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah. Department of Internal Medicine, University of Utah, Salt Lake City
| | - Garrett Morgan
- Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah
| | - Matthew J Rossman
- Department of Exercise and Sport Science, University of Utah, Salt Lake City. Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah
| | - Anthony J Donato
- Department of Exercise and Sport Science, University of Utah, Salt Lake City. Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah. Department of Internal Medicine, University of Utah, Salt Lake City. University of Utah Center on Aging, Salt Lake City
| | - Sean Runnels
- Department of Anesthesiology, University of Utah, Salt Lake City
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City
| | | | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City
| | - Russell S Richardson
- Department of Exercise and Sport Science, University of Utah, Salt Lake City. Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah. Department of Internal Medicine, University of Utah, Salt Lake City. University of Utah Center on Aging, Salt Lake City
| | - D Walter Wray
- Department of Exercise and Sport Science, University of Utah, Salt Lake City. Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah. Department of Internal Medicine, University of Utah, Salt Lake City. University of Utah Center on Aging, Salt Lake City.
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Amann M, Venturelli M, Ives SJ, Morgan DE, Gmelch B, Witman MAH, Jonathan Groot H, Walter Wray D, Stehlik J, Richardson RS. Group III/IV muscle afferents impair limb blood in patients with chronic heart failure. Int J Cardiol 2014; 174:368-75. [PMID: 24794967 DOI: 10.1016/j.ijcard.2014.04.157] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 04/13/2014] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To better understand the hemodynamic and autonomic reflex abnormalities in heart-failure patients (HF), we investigated the influence of group III/IV muscle afferents on their cardiovascular response to rhythmic exercise. METHODS Nine HF-patients (NYHA class-II, mean left ventricular ejection-fraction: 27 ± 3%) performed single leg knee-extensor exercise (25/50/80% peak-workload) under control conditions and with lumbar intrathecal fentanyl impairing μ-opioid receptor-sensitive muscle afferents. RESULTS Cardiac-output (Q) and femoral blood-flow (QL) were determined, and arterial/venous blood samples collected at each workload. Exercise-induced fatigue was estimated via pre/post-exercise changes in quadriceps strength. There were no hemodynamic differences between conditions at rest. During exercise, Q was 8-13% lower with Fentanyl-blockade, secondary to significant reductions in stroke volume and heart rate. Lower norepinephrine spillover during exercise with Fentanyl revealed an attenuated sympathetic outflow that likely contributed to the 25% increase in leg vascular conductance (p<0.05). Despite a concomitant 4% reduction in blood pressure, QL was 10-14% higher and end-exercise fatigue attenuated by 30% with Fentanyl-blockade (p<0.05). CONCLUSION/PRACTICE/IMPLICATIONS Although group III/IV muscle afferents play a critical role for central hemodynamics in HF-patients, it also appears that these sensory neurons cause excessive sympatho-excitation impairing QL which likely contributes to the exercise intolerance in this population.
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Affiliation(s)
- Markus Amann
- Department of Medicine, University of Utah, Salt Lake City, UT, USA; Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, VAMC Salt Lake City, UT, USA.
| | | | - Stephen J Ives
- Geriatric Research, Education, and Clinical Center, VAMC Salt Lake City, UT, USA
| | - David E Morgan
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Benjamin Gmelch
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Melissa A H Witman
- Geriatric Research, Education, and Clinical Center, VAMC Salt Lake City, UT, USA
| | - H Jonathan Groot
- Geriatric Research, Education, and Clinical Center, VAMC Salt Lake City, UT, USA
| | - D Walter Wray
- Department of Medicine, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, VAMC Salt Lake City, UT, USA
| | - Josef Stehlik
- Department of Medicine, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Department of Medicine, University of Utah, Salt Lake City, UT, USA; Geriatric Research, Education, and Clinical Center, VAMC Salt Lake City, UT, USA
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Trinity JD, Groot HJ, Layec G, Rossman MJ, Ives SJ, Morgan DE, Gmelch BS, Bledsoe A, Richardson RS. Nitric oxide‐mediated vascular function in response to limb movement: the impact of age. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1136.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Joel Douglas Trinity
- Geriatric Research Educational and Clinical CenterVeterans Affairs Medical Center, Salt Lake City, UtahSalt Lake CityUT
| | - H. Jonathan Groot
- Department of Exercise and Sport ScienceUniversity of UtahSalt Lake CityUT
| | - Gwenael Layec
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
| | - Matthew J Rossman
- Department of Exercise and Sport ScienceUniversity of UtahSalt Lake CityUT
| | - Stephen J Ives
- Geriatric Research Educational and Clinical CenterVeterans Affairs Medical Center, Salt Lake City, UtahSalt Lake CityUT
| | | | - Ben S Gmelch
- AnesthesiologyUniversity of UtahSalt Lake CityUT
| | | | - Russell S Richardson
- Geriatric Research Educational and Clinical CenterVeterans Affairs Medical Center, Salt Lake City, UtahSalt Lake CityUT
- Department of Internal MedicineUniversity of UtahSalt Lake CityUT
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Barrett‐O'Keefe Z, Ives SJ, Trinity JD, Witman MA, Rossman MJ, Groot HJ, Morgan DE, Gmelch B, Richardson RS, Wray DW. Is Sympathetic Restraint of Skeletal Muscle Blood Flow Present During Exercise? FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.1136.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Zachary Barrett‐O'Keefe
- Exercise and Sport ScienceUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
| | - Stephen J. Ives
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
| | - Joel D. Trinity
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
| | - Melissa A.H. Witman
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
| | - Matthew J. Rossman
- Exercise and Sport ScienceUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
| | - H. Jonathan Groot
- Exercise and Sport ScienceUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
| | | | | | - Russell S. Richardson
- Exercise and Sport ScienceUniversity of UtahSalt Lake CityUT
- Internal MedicineUniversity of UtahSalt Lake CityUT
| | - David Walter Wray
- Internal MedicineUniversity of UtahSalt Lake CityUT
- Geriatric Research, EducationClinical CenterVeterans Affairs Medical CenterSalt Lake CityUT
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Ives S, Amann M, Venturelli M, Groot HJ, Witman MA, Morgan DE, Wray DW, Richardson RS. Limb Movement‐Induced Central and Peripheral Hemodynamics in Heart Failure: The Role of Afferent Feedback. FASEB J 2013. [DOI: 10.1096/fasebj.27.1_supplement.943.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Stephen Ives
- Internal Medicine, Division of GeriatricsUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
| | - Markus Amann
- Internal Medicine, Division of GeriatricsUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
| | - Massimo Venturelli
- Internal Medicine, Division of GeriatricsUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
| | - H. Jonathan Groot
- Exercise & Sport ScienceUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
| | - Melissa A.H. Witman
- Internal Medicine, Division of GeriatricsUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
| | | | - D. Walter Wray
- Internal Medicine, Division of GeriatricsUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
| | - Russell S. Richardson
- Internal Medicine, Division of GeriatricsUniversity of UtahSalt Lake CityUT
- GeriatricsVA Medical CenterSalt Lake CityUT
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Barrett-O'Keefe Z, Ives SJ, Trinity JD, Morgan G, Rossman MJ, Donato AJ, Runnels S, Morgan DE, Gmelch BS, Bledsoe AD, Richardson RS, Wray DW. Taming the "sleeping giant": the role of endothelin-1 in the regulation of skeletal muscle blood flow and arterial blood pressure during exercise. Am J Physiol Heart Circ Physiol 2012; 304:H162-9. [PMID: 23103494 DOI: 10.1152/ajpheart.00603.2012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The cardiovascular response to exercise is governed by a combination of vasodilating and vasoconstricting influences that optimize exercising muscle perfusion while protecting mean arterial pressure (MAP). The degree to which endogenous endothelin (ET)-1, the body's most potent vasoconstrictor, participates in this response is unknown. Thus, in eight young (24 ± 2 yr), healthy volunteers, we examined leg blood flow, MAP, tissue oxygenation, heart rate, leg arterial-venous O(2) difference, leg O(2) consumption, pH, and net ET-1 and lactate release at rest and during knee extensor exercise (0, 5, 10, 15, 20, and 30 W) before and after an intra-arterial infusion of BQ-123 [ET subtype A (ET(A)) receptor antagonist]. At rest, BQ-123 did not evoke a change in leg blood flow or MAP. During exercise, net ET-1 release across the exercising leg increased approximately threefold. BQ-123 increased leg blood flow by ~20% across all work rates (changes of 113 ± 76, 176 ± 83, 304 ± 108, 364 ± 130, 502 ± 117, and 570 ± 178 ml/min at 0, 5, 10, 15, 20, and 30 W, respectively) and attenuated the exercise-induced increase in MAP by ~6%. The increase in leg blood flow was accompanied by a ~9% increase in leg O(2) consumption with an unchanged arterial-venous O(2) difference and deoxyhemoglobin, suggesting a decline in intramuscular efficiency after ET(A) receptor blockade. Together, these findings identify a significant role of the ET-1 pathway in the cardiovascular response to exercise, implicating vasoconstriction via the ET(A) receptor as an important mechanism for both the restraint of blood flow in the exercising limb and maintenance of MAP in healthy, young adults.
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Patel BN, Thomas JV, Lockhart ME, Berland LL, Morgan DE. Single-source dual-energy spectral multidetector CT of pancreatic adenocarcinoma: optimization of energy level viewing significantly increases lesion contrast. Clin Radiol 2012; 68:148-54. [PMID: 22889459 DOI: 10.1016/j.crad.2012.06.108] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 05/30/2012] [Accepted: 06/11/2012] [Indexed: 10/28/2022]
Abstract
AIM To evaluate lesion contrast in pancreatic adenocarcinoma patients using spectral multidetector computed tomography (MDCT) analysis. MATERIALS AND METHODS The present institutional review board-approved, Health Insurance Portability and Accountability Act of 1996 (HIPAA)-compliant retrospective study evaluated 64 consecutive adults with pancreatic adenocarcinoma examined using a standardized, multiphasic protocol on a single-source, dual-energy MDCT system. Pancreatic phase images (35 s) were acquired in dual-energy mode; unenhanced and portal venous phases used standard MDCT. Lesion contrast was evaluated on an independent workstation using dual-energy analysis software, comparing tumour to non-tumoural pancreas attenuation (HU) differences and tumour diameter at three energy levels: 70 keV; individual subject-optimized viewing energy level (based on the maximum contrast-to-noise ratio, CNR); and 45 keV. The image noise was measured for the same three energies. Differences in lesion contrast, diameter, and noise between the different energy levels were analysed using analysis of variance (ANOVA). Quantitative differences in contrast gain between 70 keV and CNR-optimized viewing energies, and between CNR-optimized and 45 keV were compared using the paired t-test. RESULTS Thirty-four women and 30 men (mean age 68 years) had a mean tumour diameter of 3.6 cm. The median optimized energy level was 50 keV (range 40-77). The mean ± SD lesion contrast values (non-tumoural pancreas - tumour attenuation) were: 57 ± 29, 115 ± 70, and 146 ± 74 HU (p = 0.0005); the lengths of the tumours were: 3.6, 3.3, and 3.1 cm, respectively (p = 0.026); and the contrast to noise ratios were: 24 ± 7, 39 ± 12, and 59 ± 17 (p = 0.0005) for 70 keV, the optimized energy level, and 45 keV, respectively. For individuals, the mean ± SD contrast gain from 70 keV to the optimized energy level was 59 ± 45 HU; and the mean ± SD contrast gain from the optimized energy level to 45 keV was 31 ± 25 HU (p = 0.007). CONCLUSION Significantly increased pancreatic lesion contrast was noted at lower viewing energies using spectral MDCT. Individual patient CNR-optimized energy level images have the potential to improve lesion conspicuity.
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Affiliation(s)
- B N Patel
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35249-6830, USA
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Amann M, Runnels S, Morgan DE, Trinity JD, Fjeldstad AS, Wray DW, Reese VR, Richardson RS. On the contribution of group III and IV muscle afferents to the circulatory response to rhythmic exercise in humans. J Physiol 2011; 589:3855-66. [PMID: 21646407 DOI: 10.1113/jphysiol.2011.209353] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We investigated the role of skeletal muscle afferent feedback in circulatory control during rhythmic exercise in humans. Nine healthy males performed single leg knee-extensor exercise (15/30/45 watts, 3 min each) under both control conditions (Ctrl) and with lumbar intrathecal fentanyl impairing μ-opioid receptor-sensitive muscle afferents. Cardiac output and femoral blood flow were determined, and femoral arterial/venous blood samples were collected during the final minute of each workload. To rule out cephalad migration of fentanyl to the brainstem,we documented unchanged resting ventilatory responses to different levels of hypercapnia. There were no haemodynamic differences between conditions at rest. However, during exercise cardiac output was -2 % lower with fentanyl blockade compared to control (P < 0.05), secondary to a 6% and 13% reduction in heart rate and stroke volume, respectively. Throughout exercise mean arterial pressure (MAP) was reduced by 7% (P < 0.01) which is likely to have contributed to the 15% fall in femoral blood flow. However, MAP was not completely responsible for this peripheral haemodynamic change as vascular conductance was also attenuated (-9%). Evidence of increasing noradrenaline spillover (P = 0.09) implicated an elevation in sympathetic outflow in this response. The attenuated femoral blood flow during exercise with fentanyl was associated with a 17%reduction in leg O2 delivery (P < 0.01) and a concomitant rise in the arteriovenous O2 difference (4–9%), but leg O2 consumption remained 7–13% lower than control (P < 0.05). Our findings reveal an essential contribution of continuous muscle afferent feedback to ensure the appropriate haemodynamic and ultimately metabolic response to rhythmic exercise in humans
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Affiliation(s)
- Markus Amann
- Department of Medicine, University of Utah, Salt Lake City, UT,
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Amann M, Runnels S, Morgan DE, Trinity J, Fjeldstad A, Wray DW, Richardson RS. μ‐Opioid Receptor‐Sensitive Muscle Afferents Contribute to the Circulatory Response to Exercise in Humans. FASEB J 2011. [DOI: 10.1096/fasebj.25.1_supplement.1054.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Sean Runnels
- AnesthesiologyUniversity of UtahSalt Lake CityUT
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Trinity JD, Amann M, McDaniel J, Fjeldstad AS, Barrett-O'Keefe Z, Runnels S, Morgan DE, Wray DW, Richardson RS. Limb movement-induced hyperemia has a central hemodynamic component: evidence from a neural blockade study. Am J Physiol Heart Circ Physiol 2010; 299:H1693-700. [PMID: 20802133 DOI: 10.1152/ajpheart.00482.2010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this investigation was to partially remove feedback from type III/IV skeletal muscle afferents and determine how this feedback influences the central and peripheral hemodynamic responses to passive leg movement. Heart rate (HR), stroke volume (SV), cardiac output (CO), mean arterial pressure, leg vascular conductance (LVC), and leg blood flow (LBF) were measured during 2 min of passive knee extension in eight young men before and after intrathecal fentanyl injection. Passive movement increased HR by 14 beats/min from baseline to maximal response during control (CON) (65 ± 4 to 79 ± 5 beats/min, P < 0.05), whereas HR did not significantly increase with the fentanyl block (BLK). LBF and LVC increased in both conditions; however, these increases were attenuated and delayed during BLK [%change from baseline to maximum, LBF: CON 295 ± 109 vs. BLK 210 ± 86%, (P < 0.05); LVC: CON 322 ± 40% vs. BLK 231 ± 32%, (P < 0.04)]. In CON, HR, SV, CO, and LVC increased contributing to the hyperemic response. However, under BLK conditions, statistically insignificant increases in HR and SV combined to yield a small, but significant, increase in CO and an attenuated hyperemic response. Therefore, partially blocking skeletal muscle afferent feedback blunts the central hemodynamic response due to passive limb movement, which then results in an attenuated and delayed movement-induced hyperemia. In combination, these findings provide evidence that limb movement-induced hyperemia has a significant central hemodynamic component induced by peripheral nerve activation.
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Affiliation(s)
- Joel D Trinity
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center, Salt Lake City, Utah, USA.
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Abstract
BACKGROUND Self-expanding metal stents are frequently used to palliate patients with malignant dysphagia and close tracheoesophageal fistulae. Despite proper stent positioning and deployment, in a subset of patients there is no improvement in dysphagia, closure of tracheoesophageal fistulae, or resolution of anorexia. Such patients may require a PEG tube. It has been suggested that PEG placement through a preexisting esophageal stent is problematic because of the risks of gastrostomy tube impaction within the stent and resultant stent migration. METHODS Case records were retrospectively reviewed of 9 consecutive patients with indwelling esophageal self-expanding metal stents undergoing attempted PEG. OBSERVATIONS PEG tube placement was successful in all patients. In 1 patient, the stent migrated distally into the stomach during PEG placement. This was managed endoscopically without further complication. CONCLUSIONS PEG placement in patients with previously placed esophageal self-expanding metal stents is a relatively safe and feasible procedure, although stent migration may occur.
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Affiliation(s)
- D G Adler
- Departments of Internal Medicine, Divisions of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota 55905, USA
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Steel JH, Morgan DE, Poulsom R. Advantages of in situ hybridisation over direct or indirect in situ reverse transcriptase-polymerase chain reaction for localisation of galanin mRNA expression in rat small intestine and pituitary. Histochem J 2001; 33:201-11. [PMID: 11550801 DOI: 10.1023/a:1017942123195] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In situ hybridisation (ISH) and direct or indirect in situ reverse transcriptase-polymerase chain reaction (RT-PCR) were used to detect galanin mRNA in paraffin sections of rat intestine and pituitary. With conventional ISH, a subset of intestinal neuronal ganglion cells and anterior pituitary endocrine cells were labelled. Direct in situ RT-PCR also labelled some cells in pituitary but not in intestine. Negative controls were unlabelled, but sections with 3' primer alone for RT-PCR appeared positive. No signal was apparent using the indirect in situ RT-PCR method. Investigation of the specificity of solution phase RT-PCR using RNA extracts from pituitary or intestine revealed that additional PCR products were detected under some conditions. The sequences of these PCR products suggested that one was the result of mispriming and single primer PCR, which could also have occurred in situ. Alternative galanin primers gave only the predicted RT-PCR product in solution phase yet still gave artefacts in tissue sections using direct in situ RT-PCR. ISH with probes transcribed from the correct PCR product gave identical labelling to the original galanin riboprobe. In conclusion, direct in situ RT-PCR is unreliable and requires validation, while indirect in situ RT-PCR may fail even though sufficient target exists for detection with conventional sensitive riboprobe ISH.
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Affiliation(s)
- J H Steel
- Histopathology Unit, Imperial Cancer Research Fund, London, UK
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Affiliation(s)
- T H Baron
- Department of Gastroenterology and Hepatology, Mayo Medical Center, Rochester, MN, USA
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Affiliation(s)
- M E Lockhart
- Department of Radiology, University of Alabama at Birmingham, 35249-6830, USA
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Eckhoff DE, Baron TH, Blackard WG, Morgan DE, Crowe R, Sellers M, McGuire B, Contreras JL, Bynon JS. Role of ERCP in asymptomatic orthotopic liver transplant patients with abnormal liver enzymes. Am J Gastroenterol 2000; 95:141-4. [PMID: 10638573 DOI: 10.1111/j.1572-0241.2000.01675.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The safety and efficacy of endoscopic retrograde cholangiopancreatography (ERCP) in the evaluation and management of biliary tract complications after orthotopic liver transplantation (OLT) have been previously demonstrated. However, the role of ERCP in evaluating asymptomatic OLT patients with abnormal liver enzymes with a previously normal biliary tree remains poorly defined. We sought to assess the utility of ERCP in this subset of patients. METHODS A retrospective analysis of-asymptomatic OLT patients with abnormal liver enzymes evaluated by ERCP was undertaken. In addition to ERCP, all these patients had a diagnostic abdominal Doppler ultrasound, and a percutaneous liver biopsy. All patients had choledochocholedochostomy at the time of transplant and normal T-tube cholangiograms 3 months postoperatively. A radiologist, blinded to clinical findings, interpreted the ultrasound as normal, biliary dilation, or vascular abnormalities. The same radiologist interpreted ERCP findings. A pathologist, blinded to clinical findings, graded liver biopsies as normal, diagnostic, or abnormal but nondiagnostic. RESULTS Twenty-two patients underwent 23 ERCPs. Twenty-two of the 23 ERCPs were normal (96%), and one abnormal ERCP finding did not explain the liver enzyme abnormality. Liver biopsy was diagnostic in 13 of 22 (57%) and in each case the ERCP was normal. The remaining 10 liver biopsies were abnormal but nondiagnostic. Ultrasound was abnormal in five of 22 cases, but in the three cases suggesting biliary dilation, the ERCP was interpreted as normal. CONCLUSION Routine use of ERCP in evaluation of asymptomatic OLT patients with liver function test abnormalities and normal cholangiograms at 3 months was not diagnostically useful. In this subset of patients, liver biopsy was usually abnormal and frequently diagnostic and should be the initial invasive diagnostic procedure.
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Affiliation(s)
- D E Eckhoff
- University of Alabama at Birmingham, 35294-0007, USA
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Abstract
OBJECTIVE Our goal was to identify radiographic and clinical variables that correlate with bladder rupture that may then be used as selection criteria for CT cystography in trauma patients. SUBJECTS AND METHODS Hemodynamically stable trauma patients with hematuria were examined under standardized protocol with dynamic oral and i.v. contrast-enhanced CT of the abdomen and pelvis, followed immediately by CT cystography. CT cystography consisted of contiguous 5-mm axial scans of the pelvis after retrograde distention of bladder with 300-400 ml of 4% iodinated contrast material. Radiographic and clinical variables (pelvic fracture, pelvic fluid, intraabdominal visceral injury, degree of hematuria, hematocrit, units of blood transfused, base deficit, injury mechanism, seat belt use, sex, age) were assessed and statistically analyzed using the two-tailed Fisher's exact test and Wilcoxon's rank sum test. Positive and negative individual and multivariate predictors were analyzed. RESULTS Of the 157 patients entered in our study, 12 (eight males and four females) had bladder rupture. One or more pelvic fractures were present in nine (75%) of the 12 patients (p < 0.001). Pubic symphysis diastasis, sacroiliac diastasis, and sacral, iliac, and pubic rami fractures were statistically associated with bladder rupture. Isolated acetabular fractures did not correlate with rupture. Eight (67%) of the 12 patients with bladder rupture revealed on CT cystography had gross hematuria (p < 0.001). No ruptures were seen in patients with <25 RBC/HPF (red blood cells per high-power field). All patients with rupture had pelvic fluid revealed on standard contrast-enhanced CT (p < 0.001). CONCLUSION Gross hematuria, pelvic fluid, and specific pelvic fractures were highly correlated with bladder rupture; identification of these findings may help in selection of trauma patients for CT cystography.
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Affiliation(s)
- D E Morgan
- Department of Radiology, University of Alabama, Birmingham 35233, USA
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