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Butenas ALE, Flax JS, Carroll RJ, Chuwonganant CS, Baranczuk AM, Copp SW. Sex differences in the purinergic 2 receptor-mediated blood pressure response to treadmill exercise in rats with simulated peripheral artery disease. Am J Physiol Regul Integr Comp Physiol 2024; 326:R449-R460. [PMID: 38497127 DOI: 10.1152/ajpregu.00010.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 03/19/2024]
Abstract
We investigated the role played by ATP-sensitive purinergic 2 (P2) receptors in evoking the pressor response to treadmill exercise in male and female rats with and without femoral arteries that were ligated for ∼72 h to induce simulated peripheral artery disease (PAD). We hypothesized that PPADS (P2 receptor antagonist, 10 mg iv) would reduce the pressor response to 4 min of treadmill exercise (15 m·min-1, 1° incline) and steady-state exercise plasma norepinephrine (NE) values in male and female rats, and that the magnitude of effect of PPADS would be greater in rats with simulated PAD ("ligated") than in sham-operated rats. In males, PPADS significantly reduced the difference between steady-state exercise and baseline mean arterial pressure (ΔMAP) response to treadmill exercise in sham (n = 8; pre-PPADS: 12 ± 2, post-PPADS: 1 ± 5 mmHg; P = 0.037) and ligated (n = 4; pre-PPADS: 20 ± 2, post-PPADS: 11 ± 3 mmHg; P = 0.028) rats with a similar magnitude of effect observed between groups (P = 0.720). In females, PPADS had no effect on the ΔMAP response to treadmill exercise in sham (n = 6; pre-PPADS: 9 ± 2, post-PPADS: 7 ± 2 mmHg; P = 0.448) or ligated (n = 6; pre-PPADS: 15 ± 2, post-PPADS: 16 ± 3 mmHg; P = 0.684) rats. When NE values were grouped by sex independent of ligation/sham status, PPADS significantly reduced plasma NE in male (P = 0.016) and female (P = 0.027) rats. The data indicate that P2 receptors contribute to the sympathetic response to exercise in both male and female rats but that the sympathoexcitatory role for P2 receptors translates into an obligatory role in the blood pressure response to exercise in male but not in female rats.NEW & NOTEWORTHY Here, we demonstrate that purinergic 2 (P2) receptors contribute significantly to the blood pressure response to treadmill exercise in male rats both with and without simulated PAD induced by femoral artery ligation. We found no role for P2 receptors in the blood pressure response to treadmill exercise in female rats, thus revealing clear sex differences in P2 receptor-mediated blood pressure control during exercise.
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Affiliation(s)
- Alec L E Butenas
- Department of Kinesiology, Kansas State University, Manhattan, Kansas, United States
| | - Joseph S Flax
- Department of Kinesiology, Kansas State University, Manhattan, Kansas, United States
| | - Raimi J Carroll
- Department of Kinesiology, Kansas State University, Manhattan, Kansas, United States
| | - C Shane Chuwonganant
- Department of Kinesiology, Kansas State University, Manhattan, Kansas, United States
| | - Ashley M Baranczuk
- Department of Kinesiology, Kansas State University, Manhattan, Kansas, United States
| | - Steven W Copp
- Department of Kinesiology, Kansas State University, Manhattan, Kansas, United States
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Stavres J, Aultman RS, Newsome TA. Exercise pressor responses are exaggerated relative to force production during, but not following, thirty-minutes of rhythmic handgrip exercise. Eur J Appl Physiol 2024; 124:1547-1559. [PMID: 38155209 DOI: 10.1007/s00421-023-05390-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/29/2023] [Indexed: 12/30/2023]
Abstract
PURPOSE This study tested the hypothesis that blood pressure responses would increase relative to force production in response to prolonged bouts of muscular work. METHODS Fifteen individuals performed two minutes of static handgrip (SHG; 35% MVC), followed by three minutes of post-exercise-cuff-occlusion (PECO), before and after thirty minutes of rest (control), or rhythmic handgrip exercise (RHG) of the contralateral and ipsilateral forearms. Beat-by-beat recordings of mean arterial pressure (MAP), heart rate (HR), and handgrip force (kg) were averaged across one-minute periods at baseline, and minutes 5, 10, 15, 20, 25, and 30 of RHG. MAP was also normalized to handgrip force, providing a relative measure of exercise pressor responses (mmHg/kg). Hemodynamic responses to SHG and PECO were also compared before and after contralateral RHG, ipsilateral RHG, and control, respectively. Similar to the RHG trial, areas under the curve were calculated for MAP (blood pressure index; BPI) and normalized to the time tension index (BPInorm). RESULTS HR and MAP significantly increased during RHG (15.3 ± 1.4% and 20.4 ± 3.2%, respectively, both p < 0.01), while force output decreased by up to 36.6 ± 8.0% (p < 0.01). This resulted in a 51.6 ± 9.4% increase in BPInorm during 30 min of RHG (p < 0.01). In contrast, blood pressure responses to SHG and PECO were unchanged following RHG (all p ≥ 0.07), and only the mean HR (4.2 ± 1.5%, p = 0.01) and ΔHR (67.2 ± 18.1%, p < 0.01) response to SHG were exaggerated following ipsilateral RHG. CONCLUSIONS The magnitude of exercise pressor responses relative to force production progressively increases during, but not following, prolonged bouts of muscular work.
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Affiliation(s)
- Jon Stavres
- School of Kinesiology and Nutrition, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS, USA.
| | - Ryan S Aultman
- School of Kinesiology and Nutrition, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS, USA
| | - Ta'Quoris A Newsome
- School of Kinesiology and Nutrition, University of Southern Mississippi, 118 College Drive, Hattiesburg, MS, USA
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Pearse S, Léger M, Albert WJ, Cardoso M. Active workstations: A literature review on workplace sitting. J Bodyw Mov Ther 2024; 38:406-416. [PMID: 38763586 DOI: 10.1016/j.jbmt.2024.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 11/26/2023] [Accepted: 01/02/2024] [Indexed: 05/21/2024]
Abstract
The purpose of this paper is to further understand current literature on prolonged sitting, sitting posture and active sitting solutions. This paper is divided into three sections: The first section (Part I) is a comprehensive overview of the literature on how a static prolonged seated posture can affect: spinal health, trunk posture, contact pressure/discomfort development and vascular issues. The second section (Part II) reviews and qualitatively compares the four working postures recognized in ANSI/HFES 100-2007: reclined sitting, upright sitting, declined sitting and standing. The final section (Part III) is a summary of research on active chairs that revolves around the two types of movement patterns: 1- sustaining continual movement over a range of postures, occasionally reaching neutral lordosis, and 2- maintaining high frequency and duration of daily light contractile activity in the legs (or lower limbs).
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Affiliation(s)
| | - Michelle Léger
- Faculty of Kinesiology, University of New Brunswick, NB, Canada
| | - Wayne J Albert
- Faculty of Kinesiology, University of New Brunswick, NB, Canada
| | - Michelle Cardoso
- École de kinésiologie et de loisir, Université de Moncton, NB, Canada.
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Stavres J, Aultman RS, Brandner CF, Newsome TA, Vallecillo-Bustos A, Graybeal AJ. Fat-free mass is associated with exercise pressor responses, but not cold pressor responses, in humans: influence of maximal voluntary contraction. Front Sports Act Living 2024; 6:1352192. [PMID: 38510524 PMCID: PMC10952834 DOI: 10.3389/fspor.2024.1352192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 02/15/2024] [Indexed: 03/22/2024] Open
Abstract
Objective This study examined the contributions of fat mass (FM) and fat-free mass (FFM) to the magnitude of exercise pressor responses in humans. Methods The cumulative blood pressure responses (blood pressure index; BPI) to handgrip exercise (BPIhg), post-exercise-circulatory-occlusion (BPIpeco), and cold-pressor activation (BPIcpt) were collected from 67 individuals grouped by BMI (27.8 ± 7.3 kg/m2), FFM index (FFMi, 29.1 ± 3.8 kg/m2), and FM index (FMi 12.5 ± 4.8 kg/m2) quartiles. BPI responses to HG were also normalized to the time-tension index of HG, providing a relative index of exercise pressor response magnitude (BPInorm). Results BPIhg and BPIpeco were significantly elevated in the third FFMi quartile (p ≤ 0.034), while BPInorm significantly decreased in the second and fourth quartiles (p ≤ 0.029). In contrast, no differences in BPIcpt were observed across any FFMi, BMI, or FMi quartiles (p ≥ 0.268). FFM was independently associated with BPIhg, BPI-peco, and BPInorm (all p ≤ 0.049), however, FFM was eliminated as an independent predictor when maximal voluntary contraction (MVC) was included in these regression models (all p ≥ 0.495). Neither FFM nor MVC was associated with BPIcpt (p ≥ 0.229). Conclusions These findings indicate that exercise pressor responses, but not cold-pressor responses, are significantly associated with FFM in humans, and that this association is driven by FFM related differences in MVC.
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Affiliation(s)
- Jon Stavres
- School of Kinesiology and Nutrition, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Ryan S. Aultman
- School of Kinesiology and Nutrition, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Caleb F. Brandner
- School of Kinesiology and Nutrition, The University of Southern Mississippi, Hattiesburg, MS, United States
- Department of Kinesiology, Iowa State University, Ames, IA, United States
| | - Ta’Quoris A. Newsome
- School of Kinesiology and Nutrition, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Anabelle Vallecillo-Bustos
- School of Kinesiology and Nutrition, The University of Southern Mississippi, Hattiesburg, MS, United States
| | - Austin J. Graybeal
- School of Kinesiology and Nutrition, The University of Southern Mississippi, Hattiesburg, MS, United States
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Menêses A, Krastins D, Nam M, Bailey T, Quah J, Sankhla V, Lam J, Jha P, Schulze K, O'Donnell J, Magee R, Golledge J, Greaves K, Askew CD. Toward a Better Understanding of Muscle Microvascular Perfusion During Exercise in Patients With Peripheral Artery Disease: The Effect of Lower-Limb Revascularization. J Endovasc Ther 2024; 31:115-125. [PMID: 35898156 DOI: 10.1177/15266028221114722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Leg muscle microvascular blood flow (perfusion) is impaired in response to maximal exercise in patients with peripheral artery disease (PAD); however, during submaximal exercise, microvascular perfusion is maintained due to a greater increase in microvascular blood volume compared with that seen in healthy adults. It is unclear whether this submaximal exercise response reflects a microvascular impairment, or whether it is a compensatory response for the limited conduit artery flow in PAD. Therefore, to clarify the role of conduit artery blood flow, we compared whole-limb blood flow and skeletal muscle microvascular perfusion responses with exercise in patients with PAD (n=9; 60±7 years) prior to, and following, lower-limb endovascular revascularization. MATERIALS AND METHODS Microvascular perfusion (microvascular volume × flow velocity) of the medial gastrocnemius muscle was measured before and immediately after a 5 minute bout of submaximal intermittent isometric plantar-flexion exercise using contrast-enhanced ultrasound imaging. Exercise contraction-by-contraction whole-leg blood flow and vascular conductance were measured using strain-gauge plethysmography. RESULTS With revascularization there was a significant increase in whole-leg blood flow and conductance during exercise (p<0.05). Exercise-induced muscle microvascular perfusion response did not change with revascularization (pre-revascularization: 3.19±2.32; post-revascularization: 3.89±1.67 aU.s-1; p=0.38). However, the parameters that determine microvascular perfusion changed, with a reduction in the microvascular volume response to exercise (pre-revascularization: 6.76±3.56; post-revascularization: 2.42±0.69 aU; p<0.01) and an increase in microvascular flow velocity (pre-revascularization: 0.25±0.13; post-revascularization: 0.59±0.25 s-1; p=0.02). CONCLUSION These findings suggest that patients with PAD compensate for the conduit artery blood flow impairment with an increase in microvascular blood volume to maintain muscle perfusion during submaximal exercise. CLINICAL IMPACT The findings from this study support the notion that the impairment in conduit artery blood flow in patients with PAD leads to compensatory changes in microvascular blood volume and flow velocity to maintain muscle microvascular perfusion during submaximal leg exercise. Moreover, this study demonstrates that these microvascular changes are reversed and become normalized with successful lower-limb endovascular revascularization.
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Affiliation(s)
- Annelise Menêses
- VasoActive Research Group, School of Health, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | - Digby Krastins
- VasoActive Research Group, School of Health, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | - Michael Nam
- Department of Cardiology, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Tom Bailey
- VasoActive Research Group, School of Health, University of the Sunshine Coast, Sippy Downs, QLD, Australia
- Physiology and Ultrasound Laboratory in Science and Exercise, Centre for Research on Exercise, Physical Activity & Health, School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Jing Quah
- Department of Cardiology, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Vaibhav Sankhla
- Department of Cardiology, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Jeng Lam
- Department of Cardiology, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Pankaj Jha
- Department of Vascular Surgery, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Karl Schulze
- Sunshine Vascular Clinic, Buderim, QLD, Australia
| | - Jill O'Donnell
- Department of Vascular Surgery, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Rebecca Magee
- Department of Vascular Surgery, Sunshine Coast University Hospital, Birtinya, QLD, Australia
| | - Jonathan Golledge
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University and Department of Vascular and Endovascular Surgery, Townsville University Hospital, Townsville, QLD, Australia
| | - Kim Greaves
- Department of Cardiology, Sunshine Coast University Hospital, Birtinya, QLD, Australia
- Sunshine Coast Health Institute, Sunshine Coast Hospital and Health Service, Birtinya, QLD, Australia
| | - Christopher D Askew
- VasoActive Research Group, School of Health, University of the Sunshine Coast, Sippy Downs, QLD, Australia
- Sunshine Coast Health Institute, Sunshine Coast Hospital and Health Service, Birtinya, QLD, Australia
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Vrdoljak D, Foretić N, Drviš I, Ivančev V, Perić M, Dujić Ž. Do freedivers and spearfishermen differ in local muscle oxygen saturation and anaerobic power? J Sports Med Phys Fitness 2024; 64:21-29. [PMID: 37902796 DOI: 10.23736/s0022-4707.23.15185-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2023]
Abstract
BACKGROUND Freediving is defined as an activity where athletes repetitively dive and are exposed to long efforts with limited oxygen consumption. Therefore, anaerobic features are expected to be an important facet of diving performance. This study aimed to investigate differences in anaerobic capacity and local muscle oxygenation in spearfisherman and freedivers. METHODS The sample of participants included 17 male athletes (nine freedivers, and eight spearfishermen), with an average age of 37.0±8.8 years, training experience of 10.6±9.5 years, body mass of 82.5±9.5 kg and height of 184.2±5.7 cm. Anthropometric characteristics included: body mass, body height, seated height, and body fat percentage. Wingate anaerobic test was conducted, during which local muscle oxygenation was measured with a NIRS device (Moxy monitor). Wingate power outputs were measured (peak power [W/kg] and average power [W/kg]), together with muscle oxygenation variables (baseline oxygen saturation [%], desaturation slope [%/s], minimum oxygen saturation [%], half time recovery [s], and maximum oxygen saturation [%]). RESULTS The differences were not obtained between freedivers and spearfisherman in power outputs (peak power (9.24±2.08 spearfisherman; 10.68±1.04 freedivers; P=0.14); average power (6.85±0.95 spearfisherman; 7.44±0.60 freedivers; P=0.15) and muscle oxygenation parameters. However, analysis of effect size showed a moderate effect in training experience (0.71), PP (0.89), AP (0.75), Desat slope mVLR (0.66), half time recovery mVLR (0.90). CONCLUSIONS The non-existence of differences between freedivers and spearfishermen indicates similar training adaptations to the anaerobic demands. However, the results show relatively low anaerobic capacities of our divers that could serve as an incentive for the further development of these mechanisms.
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Affiliation(s)
- Dario Vrdoljak
- Faculty of Kinesiology, University of Split, Split, Croatia -
| | - Nikola Foretić
- Faculty of Kinesiology, University of Split, Split, Croatia
- High Performance Sport Center, Croatian Olympic Committee, Zagreb, Croatia
| | - Ivan Drviš
- Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia
| | | | - Mia Perić
- Faculty of Kinesiology, University of Split, Split, Croatia
| | - Željko Dujić
- School of Medicine, University of Split, Split, Croatia
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Kim DJK, Gao Z, Cui J, Leuenberger UA, Brandt K, Blaha C, Cauffman A, Aziz F, Sinoway LI. Aortic blood pressure and pulse wave indices responses to exercise in peripheral artery disease. Am J Physiol Regul Integr Comp Physiol 2023; 325:R327-R336. [PMID: 37486070 PMCID: PMC10639020 DOI: 10.1152/ajpregu.00303.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 06/29/2023] [Accepted: 07/15/2023] [Indexed: 07/25/2023]
Abstract
Peripheral artery disease (PAD) refers to obstructed blood flow in peripheral arteries typically due to atherosclerotic plaques. How PAD alters aortic blood pressure and pressure wave propagation during exercise is unclear. Thus, this study examined central blood pressure responses to plantar flexion exercise by investigating aortic pulse wave properties in PAD. Thirteen subjects with PAD and 13 healthy [age-, sex-, body mass index (BMI) matched] subjects performed rhythmic plantar flexion for 14 min or until fatigue (20 contractions/min; started at 2 kg with 1 kg/min increment up to 12 kg). Brachial (oscillometric cuff) and radial (SphygmoCor) blood pressure and derived-aortic waveforms were analyzed during supine rest and plantar flexion exercise. At rest, baseline augmentation index (P = 0.0263) and cardiac wasted energy (P = 0.0321) were greater in PAD due to earlier arrival of the reflected wave (P = 0.0289). During exercise, aortic blood pressure (aMAP) and aortic pulse pressure showed significant interaction effects (P = 0.0041 and P = 0.0109, respectively). In particular, PAD had a greater aMAP increase at peak exercise (P = 0.0147). Moreover, the tension time index was greater during exercise in PAD (P = 0.0173), especially at peak exercise (P = 0.0173), whereas the diastolic time index (P = 0.0685) was not different between the two groups. Hence, during exercise, the subendocardial viability ratio was lower in PAD (P = 0.0164), especially at peak exercise (P = 0.0164). The results suggest that in PAD, the aortic blood pressure responses and myocardial oxygen demand during exercise are increased compared with healthy controls.
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Affiliation(s)
- Danielle Jin-Kwang Kim
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Zhaohui Gao
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Jian Cui
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Urs A Leuenberger
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Kristen Brandt
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Cheryl Blaha
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Aimee Cauffman
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Faisal Aziz
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
| | - Lawrence I Sinoway
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania, United States
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Whyte E, Thomas S, Marzolini S. Muscle oxygenation of the paretic and nonparetic legs during and after exercise in chronic stroke: Implications for mobility. PM R 2023; 15:1239-1248. [PMID: 36459570 DOI: 10.1002/pmrj.12927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 10/18/2022] [Accepted: 11/14/2022] [Indexed: 12/05/2022]
Abstract
BACKGROUND Oxygen delivery and demand are reduced in the paretic leg of individuals after stroke. However, it is unknown how muscle oxygenation, the balance between delivery and utilization of oxygen at the muscle, is altered post-stroke during aerobic exercise and how it relates to mobility. OBJECTIVE To monitor muscle oxygenation changes between the paretic and nonparetic legs of individuals after stroke during treadmill exercise and the 6-minute walk test and analyze the association with mobility. DESIGN Cross-sectional study. SETTING Cardiac rehabilitation program. PATIENTS Eleven male participants were enrolled in the study. Ten men (30.8 ± 4.1 months post-stroke; age 63.9 ± 13.9 years) with hemiparetic gait pattern finished the study. METHODS OR INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Muscle oxygenation was measured with near-infrared spectroscopy placed on the vastus lateralis of each leg during treadmill exercise at the first ventilatory threshold and during a 6-minute walk test. RESULTS The desaturation slope during treadmill exercise was significantly steeper (p = .047) in the paretic (-0.7 ± 0.6%/s) compared to the nonparetic leg (-0.3 ± 0.2%/s). There was no other significant difference between legs. The 6-minute walk test distance was not correlated with 6-minute walk test muscle oxygenation in either leg (paretic: r = 0.20, p = 0.590; nonparetic: r = 0.42, p = .232). CONCLUSIONS At the onset of treadmill exercise, the paretic leg was unable to effectively match the oxygen demand and extraction of the nonparetic leg, suggesting the need for an immediate cardiovascular warmup prior to initiating moderate intensity exercise in this population. Because the exercise desaturation rate is thought to indicate increased anaerobic metabolism and lactate production, efforts to delay rapid desaturation could improve the sustainability of activities of daily living and exercise.
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Affiliation(s)
- Elizabeth Whyte
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
- KITE Research Institute, Toronto Rehabilitation Institute - University Health Network, Toronto, Ontario, Canada
| | - Scott Thomas
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
- KITE Research Institute, Toronto Rehabilitation Institute - University Health Network, Toronto, Ontario, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada
| | - Susan Marzolini
- Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, Ontario, Canada
- KITE Research Institute, Toronto Rehabilitation Institute - University Health Network, Toronto, Ontario, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Ontario, Canada
- Canadian Partnership for Stroke Recovery, Toronto, Ontario, Canada
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Stavres J, Aultman RA, Brandner CF, Newsome TA, Vallecillo-Bustos A, Wise HL, Henderson A, Stanfield D, Mannozzi J, Graybeal AJ. Hemodynamic responses to handgrip and metaboreflex activation are exaggerated in individuals with metabolic syndrome independent of resting blood pressure, waist circumference, and fasting blood glucose. Front Physiol 2023; 14:1212775. [PMID: 37608839 PMCID: PMC10441127 DOI: 10.3389/fphys.2023.1212775] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 07/27/2023] [Indexed: 08/24/2023] Open
Abstract
Introduction: Prior studies report conflicting evidence regarding exercise pressor and metaboreflex responses in individuals with metabolic syndrome (MetS). Purpose: To test the hypotheses that 1) exercise pressor and metaboreflex responses are exaggerated in MetS and 2) these differences may be explained by elevated resting blood pressure. Methods: Blood pressure and heart rate (HR) were evaluated in 26 participants (13 MetS) during 2 min of handgrip exercise followed by 3 min of post-exercise circulatory occlusion (PECO). Systolic (SBP), diastolic (DBP), and mean arterial pressure (MAP), along with HR and a cumulative blood pressure index (BPI), were compared between groups using independent samples t-tests, and analyses of covariance were used to adjust for differences in resting blood pressure, fasting blood glucose (FBG), and waist circumference (WC). Results: ΔSBP (∼78% and ∼54%), ΔMAP (∼67% and ∼55%), and BPI (∼16% and ∼20%) responses were significantly exaggerated in individuals with MetS during handgrip and PECO, respectively (all p ≤ 0.04). ΔDBP, ΔMAP, and BPI responses during handgrip remained significantly different between groups after independently covarying for resting blood pressure (p < 0.01), and after simultaneously covarying for resting blood pressure, FBG, and WC (p ≤ 0.03). Likewise, peak SBP, DBP, MAP, and BPI responses during PECO remained significantly different between groups after adjusting for resting blood pressure (p ≤ 0.03), with peak SBP, MAP, and BPI response remaining different between groups after adjusting for all three covariates simultaneously (p ≤ 0.04). Conclusion: These data suggest that exercise pressor and metaboreflex responses are significantly exaggerated in MetS independent of differences in resting blood pressure, FBG, or WC.
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Affiliation(s)
- Jon Stavres
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Ryan A. Aultman
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Caleb F. Brandner
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Ta’Quoris A. Newsome
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | | | - Havens L. Wise
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Alex Henderson
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Diavion Stanfield
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
| | - Joseph Mannozzi
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Austin J. Graybeal
- School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States
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10
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Butenas ALE, Rollins KS, Williams AC, Copp SW. Bradykinin 2 receptors contribute to the exaggerated exercise pressor reflex in a rat model of simulated peripheral artery disease. Am J Physiol Regul Integr Comp Physiol 2023; 324:R183-R195. [PMID: 36534589 PMCID: PMC9886358 DOI: 10.1152/ajpregu.00274.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022]
Abstract
We investigated the role played by bradykinin 2 (B2) receptors in the exaggerated exercise pressor reflex in rats with a femoral artery ligated for 72 h to induce simulated peripheral artery disease (PAD). We hypothesized that in decerebrate, unanesthetized rats with a ligated femoral artery, hindlimb arterial injection of HOE-140 (100 ng, B2 receptor antagonist) would reduce the pressor response to 30 s of electrically induced 1 Hz hindlimb skeletal muscle contraction, and 30 s of 1 Hz hindlimb skeletal muscle stretch (a model of mechanoreflex activation isolated from contraction-induced metabolite production). We hypothesized no effect of HOE-140 in sham-operated "freely perfused" rats. In both freely perfused (n = 4) and "ligated" (n = 4) rats, we first confirmed efficacious B2 receptor blockade by demonstrating that HOE-140 injection significantly reduced (P < 0.05) the peak increase in mean arterial pressure (peak ΔMAP) in response to hindlimb arterial injection of bradykinin. In subsequent experiments, we found that HOE-140 reduced the peak ΔMAP response to muscle contraction in ligated (n = 14; control: 23 ± 2; HOE-140: 17 ± 2 mmHg; P = 0.03) but not freely perfused rats (n = 7; control: 17 ± 3; HOE-140: 18 ± 4 mmHg; P = 0.65). Furthermore, HOE-140 had no effect on the peak ΔMAP response to stretch in ligated rats (n = 14; control: 37 ± 4; HOE-140: 32 ± 5 mmHg; P = 0.13) but reduced the integrated area under the blood pressure signal over the final ∼20 s of the maneuver. The data suggest that B2 receptors contribute to the exaggerated exercise pressor reflex in rats with simulated PAD, and that contribution includes a modest role in the chronic sensitization of the mechanically activated channels/afferents that underlie mechanoreflex activation.
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Affiliation(s)
- Alec L E Butenas
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Korynne S Rollins
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Auni C Williams
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Steven W Copp
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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11
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Luck JC, Sica CT, Blaha C, Cauffman A, Vesek J, Eckenrode J, Stavres J. Agreement between multiparametric MRI (PIVOT), Doppler ultrasound, and near-infrared spectroscopy-based assessments of skeletal muscle oxygenation and perfusion. Magn Reson Imaging 2023; 96:27-37. [PMID: 36396004 PMCID: PMC9789193 DOI: 10.1016/j.mri.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/24/2022] [Accepted: 11/03/2022] [Indexed: 11/16/2022]
Abstract
Skeletal muscle perfusion and oxygenation are commonly evaluated using Doppler ultrasound and near-infrared spectroscopy (NIRS) techniques. However, a recently developed magnetic resonance imaging (MRI) sequence, termed PIVOT, permits the simultaneous collection of skeletal muscle perfusion and T2* (an index of skeletal muscle oxygenation). PURPOSE To determine the level of agreement between PIVOT, Doppler ultrasound, and NIRS-based assessments of skeletal muscle perfusion and oxygenation. METHODS Twelve healthy volunteers (8 females, 25 ± 3 years, 170 ± 11 cm, 71.5 ± 8.0 kg) performed six total reactive hyperemia protocols. During three of these reactive hyperemia protocols, Tissue Saturation Index (TSI) and oxygenated hemoglobin (O2Hb) were recorded from the medial gastrocnemius (MG) and tibialis anterior (TA), and blood flow velocity was recorded from the popliteal artery (BFvpop) via Doppler Ultrasound. The other three trials were performed inside the bore of a 3 T MRI scanner, and the PIVOT sequence was used to assess perfusion (PIVOTperf) and oxygenation (T2*) of the medial gastrocnemius and tibialis anterior muscles. Positive incremental areas under the curve (iAUC) and times to peak (TTP) were calculated for each variable, and the level of agreement between collection methods was evaluated via Bland-Altman analyses and Spearman's Rho correlation analyses. RESULTS The only significant bivariate relationships observed were between the T2* vs. TSI iAUC and PIVOTperf vs. BFvpop values recorded from the MG. Significant mean differences were observed for all comparisons (all P ≤ 0.038), and significant proportional biases were observed for the PIVOTperf vs. tHb TTP (R2 = 0.848, P < 0.001) and T2* vs. TSI TTP comparisons in the TA (R2 = 0.488, P = 0.011), and the PIVOTperf vs. BFvpop iAUC (R2 = 0.477, P = 0.013) and time to peak (R2 = 0.851, P < 0.001) comparisons in the MG. CONCLUSIONS Our findings suggest that the PIVOT technique has, at best, a moderate level of agreement with Doppler ultrasound and NIRS assessment methods and is subject to significant proportional bias. These findings do not challenge the accuracy of either measurement technique but instead reflect differences in the vascular compartments, sampling volumes, and parameters being evaluated.
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Affiliation(s)
- J Carter Luck
- Penn State Heart and Vascular Institute, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, United States of America
| | - Christopher T Sica
- Department of Radiology, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, United States of America
| | - Cheryl Blaha
- Penn State Heart and Vascular Institute, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, United States of America
| | - Aimee Cauffman
- Penn State Heart and Vascular Institute, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, United States of America
| | - Jeffrey Vesek
- Department of Molecular Biology, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, United States of America
| | - John Eckenrode
- School of Medicine, University of South Carolina, Columbia, SC, United States of America
| | - Jon Stavres
- Penn State Heart and Vascular Institute, Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey, PA, United States of America; School of Kinesiology and Nutrition, University of Southern Mississippi, Hattiesburg, MS, United States of America.
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12
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Joseph S, Munshi B, Agarini R, Kwok RCH, Green DJ, Jansen S. Near infrared spectroscopy in peripheral artery disease and the diabetic foot: A systematic review. Diabetes Metab Res Rev 2022; 38:e3571. [PMID: 35939767 DOI: 10.1002/dmrr.3571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 05/03/2022] [Accepted: 07/01/2022] [Indexed: 11/08/2022]
Abstract
With the need for tools that assess microvascular status in diabetic foot disease (DFD) being clear, near infrared spectroscopy (NIRS) is a putative method for noninvasive testing of the diabetic foot. The use of NIRS in patients with peripheral arterial disease (PAD) has extended to its role in studying the pathophysiology of DFD. NIRS generates metrics such as recovery time, deoxygenation, oxygen consumption (VO2 ), tissue oxygen saturation (StO2 ), total haemoglobin (HbT), and oxyhaemoglobin area under the curve (O2 HbAUC ). NIRS may potentially help the multidisciplinary team stratify limbs as high-risk, especially in diabetic patients with symptoms masked by peripheral neuropathy. NIRS may be useful for assessing treatment effectiveness and preventing deterioration of patients with PAD.
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Affiliation(s)
- Simon Joseph
- Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Bijit Munshi
- Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Raden Agarini
- Physiology Department, Faculty of Medicine, Airlangga University, Surabaya, East Java, Indonesia
- School of Human Sciences (Exercise and Sport Sciences), The University of Western Australia, Perth, Western Australia, Australia
| | - Ricky Chi Ho Kwok
- Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Daniel J Green
- School of Human Sciences (Exercise and Sport Sciences), The University of Western Australia, Perth, Western Australia, Australia
| | - Shirley Jansen
- Department of Vascular and Endovascular Surgery, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
- Heart and Vascular Research Institute, Harry Perkins Institute of Medical Research, Perth, Western Australia, Australia
- Curtin Medical School, Curtin University, Perth, Western Australia, Australia
- School of Medicine, The University of Western Australia, Perth, Western Australia, Australia
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13
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Léger MC, Cardoso MR, Dion C, Albert WJ. Does active sitting provide more physiological changes than traditional sitting and standing workstations? APPLIED ERGONOMICS 2022; 102:103741. [PMID: 35287085 DOI: 10.1016/j.apergo.2022.103741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 02/25/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
This cross-sectional study examined the physiological effects of two active chairs (AC1: had the feature to pedal and slide forward; AC2: was a multiaxial chair) compared to a traditional office chair and standing workstation. Twenty-four healthy participants computed at each of the workstations for 60 min. The active protocol was to alternate between a pedalling/side-to-side motion and sliding forward/front-to-back motion to the sound of a metronome operating at 40 bpm. The participants' physiological effects were recorded using near-infrared spectroscopy (NIRS); electrodermal activity (EDA) and a heart rate (HR) monitor for each collection period. Statistical analysis was conducted using a repeated measures analysis of variance for within-task and between-workstation comparisons. A Tukey's post hoc analysis was calculated for significant findings. Both active chairs significantly increased oxygenated blood in the gastrocnemius and participants' heart rate and EDA (stress) levels were affected slightly by task and time. However, participants felt more "productive" sitting in the control chair than in either of the active chairs.
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Affiliation(s)
| | | | - Cynthia Dion
- École de kinésiologie et de loisir, Université de Moncton, NB, Canada
| | - Wayne J Albert
- Faculty of Kinesiology, University of New Brunswick, NB, Canada
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14
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Lanzi S, Nussbaumer P, Calanca L, Mazzolai L, Malatesta D. Descending stair walking in patients with symptomatic lower extremity peripheral artery disease: A pilot study. Vasc Med 2021; 27:171-173. [PMID: 34865584 PMCID: PMC8996288 DOI: 10.1177/1358863x211058784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Stefano Lanzi
- Heart and Vessel Department, Division of Angiology, Lausanne University Hospital, Lausanne, Vaud, Switzerland
| | - Paula Nussbaumer
- Institute of Sport Sciences, University of Lausanne, Lausanne, Vaud, Switzerland
| | - Luca Calanca
- Heart and Vessel Department, Division of Angiology, Lausanne University Hospital, Lausanne, Vaud, Switzerland
| | - Lucia Mazzolai
- Heart and Vessel Department, Division of Angiology, Lausanne University Hospital, Lausanne, Vaud, Switzerland
| | - Davide Malatesta
- Institute of Sport Sciences, University of Lausanne, Lausanne, Vaud, Switzerland
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15
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Rollins KS, Butenas ALE, Williams AC, Copp SW. Sensory neuron inositol 1,4,5-trisphosphate receptors contribute to chronic mechanoreflex sensitization in rats with simulated peripheral artery disease. Am J Physiol Regul Integr Comp Physiol 2021; 321:R768-R780. [PMID: 34494467 PMCID: PMC8616625 DOI: 10.1152/ajpregu.00165.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/02/2021] [Accepted: 09/03/2021] [Indexed: 11/22/2022]
Abstract
The mechanoreflex is exaggerated in patients with peripheral artery disease (PAD) and in a rat model of simulated PAD in which a femoral artery is chronically (∼72 h) ligated. We found recently that, in rats with a ligated femoral artery, blockade of thromboxane A2 (TxA2) receptors on the sensory endings of thin fiber muscle afferents reduced the pressor response to 1 Hz repetitive/dynamic hindlimb skeletal muscle stretch (a model of mechanoreflex activation isolated from contraction-induced metabolite production). Conversely, we found no effect of TxA2 receptor blockade in rats with freely perfused femoral arteries. Here, we extended the isolated mechanoreflex findings in "ligated" rats to experiments evoking dynamic hindlimb skeletal muscle contractions. We also investigated the role played by inositol 1,4,5-trisphosphate (IP3) receptors, receptors associated with intracellular signaling linked to TxA2 receptors, in the exaggerated response to dynamic mechanoreflex and exercise pressor reflex activation in ligated rats. Injection of the TxA2 receptor antagonist daltroban into the arterial supply of the hindlimb reduced the pressor response to 1 Hz dynamic contraction in ligated but not "freely perfused" rats. Moreover, injection of the IP3 receptor antagonist xestospongin C into the arterial supply of the hindlimb reduced the pressor response to 1 Hz dynamic stretch and contraction in ligated but not freely perfused rats. These findings demonstrate that, in rats with a ligated femoral artery, sensory neuron TxA2 receptor and IP3 receptor-mediated signaling contributes to a chronic sensitization of the mechanically activated channels associated with the mechanoreflex and the exercise pressor reflex.
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Affiliation(s)
- Korynne S Rollins
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Alec L E Butenas
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Auni C Williams
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Steven W Copp
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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16
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Slysz JT, Tian L, Zhao L, Zhang D, McDermott MM. Effects of supervised exercise therapy on blood pressure and heart rate during exercise, and associations with improved walking performance in peripheral artery disease: Results of a randomized clinical trial. J Vasc Surg 2021; 74:1589-1600.e4. [PMID: 34090987 DOI: 10.1016/j.jvs.2021.05.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/01/2021] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Supervised exercise therapy (SET) improves walking ability in people with peripheral artery disease (PAD). However, the effects of SET on cardiovascular health in PAD remain unclear. Using data from a randomized clinical trial, this post hoc analyses investigated the effects of a 6-month SET intervention, compared with a control group, on changes in blood pressure (BP) and heart rate (HR) during a graded treadmill exercise test in people with PAD. METHODS We randomized 210 participants with PAD to either SET (3× weekly) or control (1× weekly health lectures) for 6 months. A graded treadmill exercise test, 6-minute walk test, and Walking Impairment Questionnaire were completed at baseline and the 6-month follow-up. BP and HR were measured at the end of each 2-minute stage of the graded treadmill exercise test. Mixed effects regression models compared the overall mean 6-month change in systolic BP, diastolic BP, pulse pressure (PP), and HR during the first 5 stages of the graded treadmill exercise test between groups. RESULTS Of the 210 randomized participants with PAD, 176 (67 ± 9 years; 72 [41%] female, 115 [65%] Black) completed the graded treadmill exercise test at baseline and the 6-month follow-up. Compared with the control group at the 6-month follow-up, SET significantly decreased overall mean systolic BP (-12 mm Hg; P < .001), PP (-9 mm Hg; P < .001), and HR (-7 b/min; P < .01) during a graded treadmill exercise test but not diastolic BP. Among participants randomized to SET, a greater decrease in systolic BP, PP, and HR during a graded treadmill exercise test was significantly associated with a greater improvement in 6-minute walk distance (systolic BP, r = -0.19 [P = .03] and PP, r = -0.23 [P < .01]; and HR, r = -0.21 [P < .01]) and with maximal treadmill walking distance (systolic BP, r = -0.21 [P < .01] and PP, r = -0.17 [P = .03]) at the 6-month follow-up. A greater decrease in the HR during a graded treadmill exercise test was significantly associated with a better WIQ distance score (r = -0.27; P = .03) at the 6-month follow-up. CONCLUSIONS In people with PAD, compared with a control group, SET improved cardiovascular health, measured by changes in BP and HR during exercise. The degree of improvement in cardiovascular health correlated with the degree of improvement in walking performance in people with PAD. NCT: 01408901.
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Affiliation(s)
- Joshua T Slysz
- Deparment of Medicine, Feinberg School of Medicine, Northwestern Univeristy, Chicago
| | - Lu Tian
- Department of Biomedical Data Science, Stanford University, Palo Alto, Calif
| | - Lihui Zhao
- Deparment of Medicine, Feinberg School of Medicine, Northwestern Univeristy, Chicago
| | - Dongxue Zhang
- Deparment of Medicine, Feinberg School of Medicine, Northwestern Univeristy, Chicago
| | - Mary M McDermott
- Deparment of Medicine, Feinberg School of Medicine, Northwestern Univeristy, Chicago.
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17
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Stavres J, Luck JC, Ducrocq GP, Cauffman AE, Pai S, Sinoway LI. Central and peripheral modulation of exercise pressor reflex sensitivity after nonfatiguing work. Am J Physiol Regul Integr Comp Physiol 2020; 319:R575-R583. [PMID: 32877237 DOI: 10.1152/ajpregu.00127.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Autonomic blood pressure control is fundamentally altered during a single bout of exercise, as evidenced by the downward resetting of the baroreflex following exercise (postexercise hypotension). However, it is unclear if an acute bout of exercise is also associated with a change in the sensitivity of the exercise pressor response to a controlled stimulus, such as a static contraction. This study tested the hypothesis that the blood pressure response to a controlled static contraction would be attenuated after unilateral cycling of the contralateral (opposite) leg, but preserved after cycling of the ipsilateral (same) leg. To test this, the blood pressure response to 90 s of isometric plantar flexion [50% maximal voluntary contraction (MVC)] was compared before and after 20 min of contralateral and ipsilateral single-leg cycling at 20% peak oxygen consumption and rest (control) in 10 healthy subjects (three males and seven females). The mean arterial pressure response was significantly attenuated after contralateral single-leg cycling (+9.8 ± 7.5% ∆mmHg vs. +6.7 ± 6.6% ∆mmHg pre and postexercise, respectively, P = 0.04) and rest (+9.0 ± 7.5% ∆mmHg vs. +6.6 ± 5.2% ∆mmHg pre and postexercise, respectively, P = 0.03). In contrast, the pressor response nonsignificantly increased following ipsilateral single-leg cycling (+5.5 ± 5.2% ∆mmHg vs. +8.9 ± 7.2% ∆mmHg pre and postexercise, respectively, P = 0.08). The heart rate, leg blood flow, and leg conductance responses to plantar flexion were not affected by any condition (P ≥ 0.12). These results are consistent with the notion that peripheral, but not central mechanisms promote exercise pressor reflex sensitivity after exercise.
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Affiliation(s)
- Jon Stavres
- Penn State Heart and Vascular Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - J Carter Luck
- Penn State Heart and Vascular Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Guillaume P Ducrocq
- Penn State Heart and Vascular Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Aimee E Cauffman
- Penn State Heart and Vascular Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Samuel Pai
- Penn State Heart and Vascular Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Lawrence I Sinoway
- Penn State Heart and Vascular Institute, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
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18
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Rollins KS, Butenas ALE, Felice KP, Matney JE, Williams AC, Kleweno TE, Copp SW. Thromboxane A 2 receptors mediate chronic mechanoreflex sensitization in a rat model of simulated peripheral artery disease. Am J Physiol Heart Circ Physiol 2020; 319:H320-H330. [PMID: 32530751 DOI: 10.1152/ajpheart.00255.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The exercise pressor reflex is a feedback autonomic and cardiovascular control mechanism evoked by mechanical and metabolic signals within contracting skeletal muscles. The mechanically sensitive component of the reflex (the mechanoreflex) is exaggerated in patients with peripheral artery disease (PAD) and in a rat model of simulated PAD in which a femoral artery is chronically ligated. Products of cyclooxygenase enzyme activity have been shown to chronically sensitize the mechanoreflex in PAD, but the identity of the muscle afferent receptors that mediate the sensitization is unclear. We hypothesized that injection of the endoperoxide 4 receptor (EP4-R) antagonist L161982 or the thromboxane A2 receptor (TxA2-R) antagonist daltroban into the arterial supply of the hindlimb would reduce the pressor response to repetitive, dynamic hindlimb skeletal muscle stretch (a model of isolated mechanoreflex activation) in rats with a femoral artery that was ligated ~72 h before the experiment but not in rats with freely perfused femoral arteries. We found that EP4-R blockade had no effect on the pressor response (peak Δmean arterial pressure) to stretch in freely perfused (n = 6, pre: 14 ± 2, post: 15 ± 2 mmHg, P = 0.97) or ligated (n = 8, pre: 29 ± 4, post: 29 ± 6 mmHg, P = 0.98) rats. In contrast, TxA2-R blockade had no effect on the pressor response to stretch in freely perfused rats (n = 6, pre: 16 ± 3, post: 17 ± 4 mmHg, P = 0.99) but significantly reduced the response in ligated rats (n = 11, pre: 29 ± 4, post: 17 ± 5 mmHg, P < 0.01). We conclude that TxA2-Rs contribute to chronic mechanoreflex sensitization in the chronic femoral artery-ligated rat model of simulated PAD.NEW & NOTEWORTHY We demonstrate that thromboxane A2 receptors, but not endoperoxide 4 receptors, on the sensory endings of thin fiber muscle afferents contribute to the chronic sensitization of the muscle mechanoreflex in rats with a ligated femoral artery (a model of simulated peripheral artery disease). The data may have important implications for our understanding of blood pressure control during exercise in patients with peripheral artery disease.
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Affiliation(s)
- Korynne S Rollins
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Alec L E Butenas
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Kennedy P Felice
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Jacob E Matney
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Auni C Williams
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Talyn E Kleweno
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Steven W Copp
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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Kim DJK, Montgomery PS, Wang M, Shen B, Kuroki M, Gardner AW. Patients With Peripheral Arterial Disease With Exaggerated Pressor Response Have Greater Ambulatory Dysfunction Than Patients With Lower Pressor Response. Angiology 2020; 71:747-753. [PMID: 32425059 DOI: 10.1177/0003319720925970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We determined whether patients with peripheral arterial disease (PAD) who have either an exaggerated or a negative pressor response during treadmill walking have shorter peak walking time (PWT) and claudication onset time (COT) than patients with a normal pressor response, independent of comorbid conditions. A total of 249 patients were categorized to 1 of 3 groups based on systolic blood pressure (SBP) responses at 2 minutes of treadmill walking (speed = 2 mph, grade = 0%): group 1 (negative pressor response, SBP < 0 mm Hg), group 2 (normal pressor response, SBP 18 mm Hg), and group 3 (exaggerated pressor response, SBP > 18 mm Hg). After adjusting for comorbid conditions, group 3 (exaggerated) had significantly reduced COT (P = .011) and PWT (P = .002) compared to group 2 (normal), while group 1 (negative) and group 2 (normal) were not different. Patients with symptomatic PAD with an increase in SBP > 18 mm Hg after 2 minutes of treadmill walking experience claudication earlier and thus have greater ambulatory dysfunction, compared to patients with PAD with a normal pressor response, whereas patients with PAD with negative pressor response had a similar walking performance. The implication is that the magnitude of pressor response to only 2 minutes of treadmill walking can partially explain the degree of ambulatory dysfunction in patients with PAD.
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Affiliation(s)
- Danielle Jin-Kwang Kim
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, PA, USA
| | - Polly S Montgomery
- Department of Physical Medicine and Rehabilitation, Penn State College of Medicine, Hershey, PA, USA
| | - Ming Wang
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - Biyi Shen
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA, USA
| | - Marcos Kuroki
- Department of Surgery, Penn State College of Medicine, Hershey, PA, USA
| | - Andrew W Gardner
- Department of Physical Medicine and Rehabilitation, Penn State College of Medicine, Hershey, PA, USA
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Kim DJK, Kuroki M, Cui J, Gao Z, Luck JC, Pai S, Miller A, Sinoway L. Systemic and regional hemodynamic response to activation of the exercise pressor reflex in patients with peripheral artery disease. Am J Physiol Heart Circ Physiol 2020; 318:H916-H924. [PMID: 32108523 DOI: 10.1152/ajpheart.00493.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Patients with peripheral artery disease (PAD) have an accentuated exercise pressor reflex (EPR) during exercise of the affected limb. The underlying hemodynamic changes responsible for this, and its effect on blood flow to the exercising extremity, are unclear. We tested the hypothesis that the exaggerated EPR in PAD is mediated by an increase in total peripheral resistance (TPR), which augments redistribution of blood flow to the exercising limb. Twelve patients with PAD and 12 age- and sex-matched subjects without PAD performed dynamic plantar flexion (PF) using the most symptomatic leg at progressive workloads of 2-12 kg (increased by 1 kg/min until onset of fatigue). We measured heart rate, beat-by-beat blood pressure, femoral blood flow velocity (FBV), and muscle oxygen saturation (SmO2) continuously during the exercise. Femoral blood flow (FBF) was calculated from FBV and baseline femoral artery diameter. Stroke volume (SV), cardiac output (CO), and TPR were derived from the blood pressure tracings. Mean arterial blood pressure and TPR were significantly augmented in PAD compared with control during PF. FBF increased during exercise to an equal extent in both groups. However, SmO2 of the exercising limb remained significantly lower in PAD compared with control. We conclude that the exaggerated pressor response in PAD is mediated by an abnormal TPR response, which augments redistribution of blood flow to the exercising extremity, leading to an equal rise in FBF compared with controls. However, this increase in FBF is not sufficient to normalize the SmO2 response during exercise in patients with PAD.NEW & NOTEWORTHY In this study, peripheral artery disease (PAD) patients and healthy control subjects performed graded, dynamic plantar flexion exercise. Data from this study suggest that previously reported exaggerated exercise pressor reflex in patients with PAD is driven by greater vasoconstriction in nonexercising vascular territories which also results in a redistribution of blood flow to the exercising extremity. However, this rise in femoral blood flow does not fully correct the oxygen deficit due to changes in other mechanisms that require further investigation.
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Affiliation(s)
- Danielle Jin-Kwang Kim
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Marcos Kuroki
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania.,Department of Surgery, Penn State College of Medicine, Hershey, Pennsylvania
| | - Jian Cui
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Zhaohui Gao
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - J Carter Luck
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Sam Pai
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Amanda Miller
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
| | - Lawrence Sinoway
- Penn State Heart and Vascular Institute, Penn State College of Medicine, Hershey, Pennsylvania
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21
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Cooper DM, Radom-Aizik S. Exercise-associated prevention of adult cardiovascular disease in children and adolescents: monocytes, molecular mechanisms, and a call for discovery. Pediatr Res 2020; 87:309-318. [PMID: 31649340 PMCID: PMC11177628 DOI: 10.1038/s41390-019-0581-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 08/07/2019] [Accepted: 08/15/2019] [Indexed: 12/28/2022]
Abstract
Atherosclerosis originates in childhood and adolescence. The goal of this review is to highlight how exercise and physical activity during childhood and adolescence, critical periods of growth and development, can prevent adult cardiovascular disease (CVD), particularly through molecular mechanisms of monocytes, a key cell of the innate immune system. Monocytes are heterogeneous and pluripotential cells that can, paradoxically, play a role in both the instigation and prevention of atherosclerosis. Recent discoveries in young adults reveal that brief exercise affects monocyte gene pathways promoting a cell phenotype that patrols the vascular system and repairs injuries. Concurrently, exercise inhibits pro-inflammatory monocytes, cells that contribute to vascular damage and plaque formation. Because CVD is typically asymptomatic in youth, minimally invasive techniques must be honed to study the subtle anatomic and physiologic evidence of vascular dysfunction. Exercise gas exchange and heart rate measures can be combined with ultrasound assessments of vascular anatomy and reactivity, and near-infrared spectroscopy to quantify impaired O2 transport that is often hidden at rest. Combined with functional, transcriptomic, and epigenetic monocyte expression and measures of monocyte-endothelium interaction, molecular mechanisms of early CVD can be formulated, and then translated into effective physical activity-based strategies in youth to prevent adult-onset CVD.
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Affiliation(s)
- Dan M Cooper
- Pediatric Exercise and Genomics Research Center, University of California Irvine School of Medicine, Pediatrics, Irvine, CA, USA.
| | - Shlomit Radom-Aizik
- Pediatric Exercise and Genomics Research Center, University of California Irvine School of Medicine, Pediatrics, Irvine, CA, USA
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22
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Bolton L. Peripheral arterial disease: Scoping review of patient-centred outcomes. Int Wound J 2019; 16:1521-1532. [PMID: 31597226 DOI: 10.1111/iwj.13232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 09/04/2019] [Accepted: 09/13/2019] [Indexed: 01/13/2023] Open
Abstract
Peripheral arterial disease (PAD) impairs patients' quality of life (QOL), walking and ulcer healing, increasing patient pain, costs, and risks of amputation or mortality. A literature appraisal described PAD treatment capacity to improve validated patient-centred outcomes in controlled clinical studies. The PUBMED database was searched from 1 January 1970 to 21 June 2018, for original and derivative controlled clinical trial references addressing MeSH terms for 'ischemia' AND 'leg ulcer'. Non-ischemic ulcer treatment references were excluded. Frequencies of improved (P < .05) outcomes were reported. Eighty-eight studies on 4153 patients were summarized. Walking, pain or QOL improved mainly for interventions administered before PAD became severe. Amputation incidence, pain and ulcer healing were more frequently reported in those with severe PAD. Independent of PAD severity, patients experienced more likely improved walking, QOL, or pain reduction in response to structured walking interventions or those increasing calf muscle activity. Those with more severe PAD were more likely to report amputation reduction, mainly in response to invasive interventions. Those with PAD experienced more consistently improved patient-centred outcomes if they received multidisciplinary PAD management with supervised walking or calf muscle activity, with more likely amputation risk reduced for those with more severe PAD.
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Affiliation(s)
- Laura Bolton
- Department of Surgery, Robert Wood Johnson University Hospital, New Brunswick, New Jersey
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23
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Crossley KW, Porter DA, Ellsworth J, Caldwell T, Feland JB, Mitchell U, Johnson AW, Egget D, Gifford JR. Effect of Cuff Pressure on Blood Flow during Blood Flow-restricted Rest and Exercise. Med Sci Sports Exerc 2019; 52:746-753. [PMID: 31568024 DOI: 10.1249/mss.0000000000002156] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
PURPOSE This study investigated the relationship between blood flow restriction (BFR) cuff pressure and blood flow at rest and during exercise, with the aim of determining if lower cuff pressures will provide an ischemic stimulus comparable to higher pressures. METHODS The relationship between blood flow and cuff pressure at rest was determined by measuring blood flow (Doppler Ultrasound) through the superficial femoral artery (SFA) in 23 adults across a range of pressures (0%-100% Arterial Occlusion Pressure at rest [rAOP]). The interplay between cuff pressure, blood flow and exercise was assessed by determining AOP at rest and during plantar flexion exercise (eAOP) and subsequently measuring the blood flow response to plantar flexion exercise with BFR cuff pressure set to either 40% rAOP or 40% eAOP. RESULTS At rest, a nonlinear relationship between cuff pressure and blood flow through the SFA exhibited a plateau at moderate pressures, with nonsignificant differences in blood flow (~9%, P = 1.0) appearing between pressures ranging from 40% to 80% rAOP. While eAOP was greater than rAOP (229 ± 1.5 mm Hg vs 202 ± 1.5 mm Hg, P < 0.01), blood flow during plantar flexion exercise did not significantly differ (P = 0.49) when applying 40% rAOP or 40% eAOP. CONCLUSIONS Blood flow through the SFA exhibits a nonlinear relationship with cuff pressure, such that cuff pressures in the range of 40% to 80% rAOP reduce blood flow to approximately the same degree. The BFR interventions opting for lower (e.g., 40% AOP), more comfortable pressures will likely provide an ischemic stimulus comparable to that of higher (80% AOP), less-comfortable pressures.
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Affiliation(s)
- Kent W Crossley
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Doran A Porter
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Joshua Ellsworth
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | - Tabitha Caldwell
- Department of Exercise Sciences, Brigham Young University, Provo, UT
| | | | | | | | - Dennis Egget
- Department of Statistics, Brigham Young University, Provo, UT
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24
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Stavres J, Sica CT, Blaha C, Herr M, Wang J, Pai S, Cauffman A, Vesek J, Yang QX, Sinoway LI. The exercise pressor reflex and active O 2 transport in peripheral arterial disease. Physiol Rep 2019; 7:e14243. [PMID: 31637857 PMCID: PMC6803779 DOI: 10.14814/phy2.14243] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 12/15/2022] Open
Abstract
It is unclear if the exaggerated exercise pressor reflex observed in peripheral arterial disease (PAD) patients facilitates Oxygen (O2 ) transport during presymptomatic exercise. Accordingly, this study compared O2 transport between PAD patients and healthy controls during graded presymptomatic work. Seven PAD patients and seven healthy controls performed dynamic plantar flexion in the bore of a 3T MRI scanner. Perfusion, T2 * (an index of relative tissue oxygenation), and SvO2 (a measure of venous oxygen saturation) were collected from the medial gastrocnemius (MG) during the final 10 seconds of each stage. Blood pressure was also collected during the final minute of each stage. As expected, the pressor response to presymptomatic work (4 kg) was exaggerated in PAD patients compared to controls (+14 mmHg ± 4 and +7 mmHg ± 2, P ≤ 0.034). When normalized to changes in free water content (S0 ), T2 * was lower at 2 kg in PAD patients compared to controls (-0.91 Δms/ΔAU ± 0.3 and 0.57 Δms/ΔAU ± 0.3, P ≤ 0.008); followed by a greater increase in perfusion at 4 kg in the PAD group (+18.8 mL/min/100g ± 6.2 vs. -0.21 mL/min/100g ± 3.2 in PAD and controls, P ≤ 0.026). Lastly, SvO2 decreased at 4 kg in both groups (-13% ± 4 and -2% ± 4 in PAD and controls, P ≤ 0.049), suggesting an increase in O2 extraction in the PAD group. Based on these findings, O2 transport appears to be augmented during graded presymptomatic work in PAD patients, and this may be partially mediated by an exaggerated pressor response.
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Affiliation(s)
- Jon Stavres
- Penn State Heart and Vascular InstitutePennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Christopher T. Sica
- Department of RadiologyPennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Cheryl Blaha
- Penn State Heart and Vascular InstitutePennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Michael Herr
- Penn State Heart and Vascular InstitutePennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Jianli Wang
- Department of RadiologyPennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Samuel Pai
- Penn State Heart and Vascular InstitutePennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Aimee Cauffman
- Penn State Heart and Vascular InstitutePennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Jeffrey Vesek
- Milton S. Hershey Medical Center, Department of Molecular BiologyPennsylvania State University College of MedicineHersheyPennsylvania
| | - Qing X. Yang
- Department of RadiologyPennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
- Department of NeurosurgeryPennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
| | - Lawrence I. Sinoway
- Penn State Heart and Vascular InstitutePennsylvania State University College of MedicineMilton S. Hershey Medical CenterHersheyPennsylvania
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25
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Butenas ALE, Hopkins TD, Rollins KS, Felice KP, Copp SW. Investigation of the mechanisms of cyclooxygenase-mediated mechanoreflex sensitization in a rat model of simulated peripheral artery disease. Am J Physiol Heart Circ Physiol 2019; 317:H1050-H1061. [PMID: 31469294 DOI: 10.1152/ajpheart.00399.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mechanical and metabolic stimuli within contracting skeletal muscles reflexly increase sympathetic nervous system activity and blood pressure. That reflex, termed the exercise pressor reflex, is exaggerated in patients with peripheral artery disease (PAD) and in a rat PAD model with a chronically ligated femoral artery. The cyclooxygenase (COX) pathway contributes to the exaggerated pressor response during rhythmic skeletal muscle contractions in patients with PAD, but the specific mechanism(s) of the COX-mediated exaggeration are not known. In decerebrate, unanesthetized rats with a chronically ligated femoral artery ("ligated" rats), we hypothesized that hindlimb arterial injection of the COX inhibitor indomethacin would reduce the pressor response during 1-Hz dynamic hindlimb skeletal muscle stretch; a model of the activation of the mechanical component of the exercise pressor reflex (i.e., the mechanoreflex). In ligated rats (n = 7), indomethacin reduced the pressor response during stretch (control: 30 ± 4; indomethacin: 12 ± 3 mmHg; P < 0.01), whereas there was no effect in rats with "freely perfused" femoral arteries (n = 6, control: 18 ± 5; indomethacin: 17 ± 5 mmHg; P = 0.87). In ligated rats (n = 4), systemic indomethacin injection had no effect on the pressor response during stretch. Femoral artery ligation had no effect on skeletal muscle COX protein expression or activity or concentration of the COX metabolite prostaglandin E2. Conversely, femoral artery ligation increased expression of the COX metabolite receptors endoperoxide 4 and thromboxane A2-R in dorsal root ganglia tissue. We conclude that, in ligated rats, the COX pathway sensitizes the peripheral endings of mechanoreflex afferents, which occurs principally as a result of increased expression of COX metabolite receptors.NEW & NOTEWORTHY We demonstrate that the mechanoreflex is sensitized by the cyclooxygenase (COX) pathway within hindlimb skeletal muscles in the rat chronic femoral artery ligation model of simulated peripheral artery disease (PAD). The mechanism of sensitization appears attributable to increased receptors for COX metabolites on sensory neurons and not increased concentration of COX metabolites. Our data may carry important clinical implications for patients with PAD who demonstrate exaggerated increases in blood pressure during exercise compared with healthy counterparts.
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Affiliation(s)
- Alec L E Butenas
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Tyler D Hopkins
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Korynne S Rollins
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Kennedy P Felice
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Steven W Copp
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
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26
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Quast DR, Hummel T, Wutzler A, Meier JJ. Improvement of peripheral microcirculation after cardioversion of atrial fibrillation. PACING AND CLINICAL ELECTROPHYSIOLOGY: PACE 2019; 42:830-835. [PMID: 31106433 DOI: 10.1111/pace.13723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 03/19/2019] [Accepted: 03/24/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Near-infrared spectroscopy (NIRS) is a noninvasive method to measure regional tissue oxygenation (rSO2 ). In patients with atrial fibrillation (AF), cardiac output and endothelial function are altered. Peripheral tissue oxygenation may therefore be reduced. This study aims to describe the peripheral tissue oxygenation of the feet before and after synchronized electrical cardioversion (CV) of patients with AF using NIRS. METHODS Patients with AF undergoing CV were included and screened for peripheral arterial disease (PAD), diabetes mellitus (DM), and peripheral neuropathy (PN). NIRS was performed before and after CV under continuous ECG and monitoring of peripheral oxygen saturation. NIRS was registered on the dorsoplantar and plantar area of both feet. Capillary blood gas analysis was performed and left ventricular ejection fraction (LVEF) was determined. RESULTS Twelve patients (five women, seven men, age 70.8 ± 10.8 years) participated. None had history of PAD. DM was present in three (25%) patients. Two patients (16.7%) had PN. CV was successful in 11 patients. Overall, rSO2 improved significantly in all patients after CV (P = .0003). Mean improvement was 7.17%. There were no significant changes in body temperature, ankle-brachial index, sO2 , pO2 , pCO2 , pH, or lactate after CV. Heart rate was significantly lower (P < .0001) and LVEF significantly higher (P = .0123) after CV. CONCLUSIONS In patients with AF, peripheral tissue oxygen saturation improves significantly after successful CV. This suggests that patients with PAD may not only benefit from interventional or surgical improvement of arterial vascularization, but also from CV in case of AF.
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Affiliation(s)
- Daniel Robert Quast
- Diabetes Center Bochum-Hattingen, Medical Department I, St Josef-Hospital, University Hospital of the Ruhr-University Bochum, Bochum, Germany
| | - Thomas Hummel
- Department of Vascular Surgery, St Josef-Hospital, University Hospital of the Ruhr-University Bochum, Bochum, Germany
| | - Alexander Wutzler
- Cardiovascular Center, St Josef-Hospital, University Hospital of the Ruhr-University Bochum, Bochum, Germany
| | - Juris Jendrik Meier
- Diabetes Center Bochum-Hattingen, Medical Department I, St Josef-Hospital, University Hospital of the Ruhr-University Bochum, Bochum, Germany
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27
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Proctor DN, Luck JC, Maman SR, Leuenberger UA, Muller MD. Esmolol acutely alters oxygen supply-demand balance in exercising muscles of healthy humans. Physiol Rep 2019; 6:e13673. [PMID: 29665297 PMCID: PMC5903697 DOI: 10.14814/phy2.13673] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 03/09/2018] [Indexed: 01/13/2023] Open
Abstract
Beta‐adrenoreceptor antagonists (β blockers) reduce systemic O2 delivery and blood pressure (BP) during exercise, but the subsequent effects on O2 extraction within the active limb muscles are unknown. In this study, we examined the effects of the fast‐acting, β1 selective blocker esmolol on systemic hemodynamics and leg muscle O2 saturation (near infrared spectroscopy, NIRS) during submaximal leg ergometry. Our main hypothesis was that esmolol would augment exercise‐induced reductions in leg muscle O2 saturation. Eight healthy adults (6 men, 2 women; 23–67 year) performed light and moderate intensity bouts of recumbent leg cycling before (PRE), during (β1‐blocked), and 45 min following (POST) intravenous infusion of esmolol. Oxygen uptake, heart rate (HR), BP, and O2 saturation (SmO2) of the vastus lateralis (VL) and medial gastrocnemius (MG) muscles were measured continuously. Esmolol attenuated the increases in HR and systolic BP during light (−12 ± 9 bpm and −26 ± 12 mmHg vs. PRE) and moderate intensity (−20 ± 10 bpm and −40 ± 18 mmHg vs. PRE) cycling (all P < 0.01). Exercise‐induced reductions in SmO2 occurred to a greater extent during the β1‐blockade trial in both the VL (P = 0.001 vs. PRE) and MG muscles (P = 0.022 vs. PRE). HR, SBP and SmO2 were restored during POST (all P < 0.01 vs. β1‐blocked). In conclusion, esmolol rapidly and reversibly increases O2 extraction within exercising muscles of healthy humans.
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Affiliation(s)
- David N Proctor
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania.,Penn State Heart and Vascular Institute, Penn State University College of Medicine, Hershey, Pennsylvania
| | - J Carter Luck
- Penn State Heart and Vascular Institute, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Stephan R Maman
- Penn State Heart and Vascular Institute, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Urs A Leuenberger
- Penn State Heart and Vascular Institute, Penn State University College of Medicine, Hershey, Pennsylvania
| | - Matthew D Muller
- Penn State Heart and Vascular Institute, Penn State University College of Medicine, Hershey, Pennsylvania.,Master of Science in Anesthesia Program, Case Western Reserve University School of Medicine, Cleveland, Ohio
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28
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Hotta K, Batchelor WB, Graven J, Dahya V, Noel TE, Ghai A, Katopodis JN, Dixon WC, Andrews R, Pragle A, Chheda J, Liberatore L, Behnke BJ, Muller-Delp J. Daily Passive Muscle Stretching Improves Flow-Mediated Dilation of Popliteal Artery and 6-minute Walk Test in Elderly Patients with Stable Symptomatic Peripheral Artery Disease. CARDIOVASCULAR REVASCULARIZATION MEDICINE 2019; 20:642-648. [PMID: 31171470 DOI: 10.1016/j.carrev.2019.05.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/29/2019] [Accepted: 05/02/2019] [Indexed: 11/17/2022]
Abstract
BACKGROUND Patients with peripheral arterial disease (PAD) often have walking impairment due to insufficient oxygen supply to skeletal muscle. In aged rats, we have shown that daily stretching of calf muscles improves endothelium-dependent dilation of arterioles from the soleus muscle and increases capillarity and muscle blood flow during exercise. Therefore, we hypothesized that daily muscle stretching of calf muscles would improve endothelium-dependent vasodilation of the popliteal artery and walking function in PAD patients. METHODS We performed a randomized, non-blinded, crossover study whereby 13 patients with stable symptomatic PAD were randomized to undergo either 4 weeks of passive calf muscle stretching (ankle dorsiflexion applied 30 min/d, 5 days/wk) followed by 4 weeks of no muscle stretching and vice versa. Endothelium-dependent flow-mediated dilation (FMD) and endothelium-independent nitroglycerin-induced dilation of the popliteal artery and 6 minute walk test (6MWT) were evaluated at baseline and after each 4 week interval. RESULTS After 4 weeks of muscle stretching, FMD and 6MWT improved significantly in the muscle stretching group vs. the control (FMD: 5.1 ± 0.5% vs. 3.7 ± 0.3%, P = 0.005; 6MWT continuous walking distance: 304 ± 43 m vs. 182 ± 34 m; P = 0.0006). No difference in nitroglycerin-induced dilation was found between groups (10.9 ± 1.2 vs. 9.9 ± 0.4%, P = 0.48). Post-stretching, 6MWT total walking distance was positively correlated with normalized FMD (R = 0.645, P = 0.02). CONCLUSIONS Passive calf muscle stretching enhanced vascular endothelial function and improved walking function in elderly patients with stable symptomatic PAD. These findings merit further investigation in a prospective randomized trial.
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Affiliation(s)
- Kazuki Hotta
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, USA; Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
| | | | - James Graven
- Tallahassee Memorial Healthcare, Tallahassee, FL, USA
| | | | | | - Akash Ghai
- Southern Medical Group, P.A., Tallahassee, FL, USA
| | | | | | | | - Aimee Pragle
- Florida State University College of Medicine, Tallahassee, FL, USA
| | - Jegghna Chheda
- Department of Nutrition, Food and Exercise Sciences, Florida State University College of Human Sciences, Tallahassee, FL, USA
| | - Lia Liberatore
- Department of Nutrition, Food and Exercise Sciences, Florida State University College of Human Sciences, Tallahassee, FL, USA
| | - Brad J Behnke
- Department of Kinesiology, Kansas State University College of Human Ecology, Manhattan, KS, USA
| | - Judy Muller-Delp
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, USA.
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29
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Hart CR, Layec G, Trinity JD, Le Fur Y, Gifford JR, Clifton HL, Richardson RS. Oxygen availability and skeletal muscle oxidative capacity in patients with peripheral artery disease: implications from in vivo and in vitro assessments. Am J Physiol Heart Circ Physiol 2018; 315:H897-H909. [PMID: 29932772 DOI: 10.1152/ajpheart.00641.2017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Evidence suggests that the peak skeletal muscle mitochondrial ATP synthesis rate ( Vmax) in patients with peripheral artery disease (PAD) may be attenuated due to disease-related impairments in O2 supply. However, in vitro assessments suggest intrinsic deficits in mitochondrial respiration despite ample O2 availability. To address this conundrum, Doppler ultrasound, near-infrared spectroscopy, phosphorus magnetic resonance spectroscopy, and high-resolution respirometry were combined to assess convective O2 delivery, tissue oxygenation, Vmax, and skeletal muscle mitochondrial capacity (complex I + II, state 3 respiration), respectively, in the gastrocnemius muscle of 10 patients with early stage PAD and 11 physical activity-matched healthy control (HC) subjects. All participants were studied in free-flow control conditions (FF) and with reactive hyperemia (RH) induced by a period of brief ischemia during the last 30 s of submaximal plantar flexion exercise. Patients with PAD repeated the FF and RH trials under hyperoxic conditions (FF + 100% O2 and RH + 100% O2). Compared with HC subjects, patients with PAD exhibited attenuated O2 delivery at the same absolute work rate and attenuated tissue reoxygenation and Vmax after relative intensity-matched exercise. Compared with the FF condition, only RH + 100% O2 significantly increased convective O2 delivery (~44%), tissue reoxygenation (~54%), and Vmax (~60%) in patients with PAD ( P < 0.05), such that Vmax was now not different from HC subjects. Furthermore, there was no evidence of an intrinsic mitochondrial deficit in PAD, as assessed in vitro with adequate O2. Thus, in combination, this comprehensive in vivo and in vitro investigation implicates O2 supply as the predominant factor limiting mitochondrial oxidative capacity in early stage PAD. NEW & NOTEWORTHY Currently, there is little accord as to the role of O2 availability and mitochondrial function in the skeletal muscle dysfunction associated with peripheral artery disease. This is the first study to comprehensively use both in vivo and in vitro approaches to document that the skeletal muscle dysfunction associated with early stage peripheral artery disease is predominantly a consequence of limited O2 supply and not the impact of an intrinsic mitochondrial defect in this pathology.
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Affiliation(s)
- Corey R Hart
- 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
| | - Gwenael Layec
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, 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.,Department of Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
| | - Yann Le Fur
- Centre de Résonance Magnétique Biologique et Médicale Unité Mixte de Recherché 7339, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille , France
| | - Jayson R Gifford
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah
| | - Heather L Clifton
- Geriatric Research, Education, and Clinical Center, George E. Whalen Veterans Affairs Medical Center , Salt Lake City, Utah.,Department of Medicine, Division of Geriatrics, 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 Medicine, Division of Geriatrics, University of Utah , Salt Lake City, Utah.,Department of Nutrition and Integrative Physiology, University of Utah , Salt Lake City, Utah
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30
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Kruse NT, Ueda K, Hughes WE, Casey DP. Eight weeks of nitrate supplementation improves blood flow and reduces the exaggerated pressor response during forearm exercise in peripheral artery disease. Am J Physiol Heart Circ Physiol 2018. [PMID: 29522355 DOI: 10.1152/ajpheart.00015.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Peripheral artery disease (PAD) is characterized by a reduced blood flow (BF) and an elevated blood pressure (pressor) response during lower extremity exercise. Although PAD is evident in the upper extremities, no studies have determined BF and pressor responses during upper extremity exercise in PAD. Emerging evidence suggests that inorganic nitrate supplementation may serve as an alternative dietary strategy to boost nitric oxide bioavailability, improving exercising BF and pressor responses during exercise. The present study investigated 1) BF and pressor responses to forearm exercise in patients with PAD ( n = 21) relative to healthy age-matched control subjects ( n = 16) and 2) whether 8 wk of NaNO3 supplementation influenced BF and pressor responses to forearm exercise in patients with PAD. Patients with moderate to severe PAD were randomly assigned to a NaNO3 (1 g/day, n = 13)-treated group or a placebo (microcrystalline cellulose, n = 8)-treated group. Brachial artery forearm BF (FBF; via Doppler) and blood pressure (via finger plethysmography) were measured during mild-intensity (~3.5-kg) and moderate-intensity (~7-kg) handgrip exercise. The absolute change (from baseline) in FBF was reduced (except in the 3.5-kg condition) and BP responses were increased in patients with PAD compared with healthy control subjects in 3.5- and 7-kg conditions (all P < 0.05). Plasma nitrate and nitrite were elevated, exercising (7-kg) ΔFBF was improved (from 141 ± 17 to 172 ± 20 ml/min), and mean arterial pressure response was reduced (from 13 ± 1 to 9 ± 1 mmHg, P < 0.05) in patients with PAD that received NaNO3 supplementation for 8 wk relative to those that received placebo. These results suggest that the BF limitation and exaggerated pressor response to moderate-intensity forearm exercise in patients with PAD are improved with 8 wk of NaNO3 supplementation. NEW & NOTEWORTHY Peripheral artery disease (PAD) results in an exaggerated pressor response and reduced blood flow during lower limb exercise; however, the effect of PAD in the upper limbs has remained unknown. These results suggest that 8 wk of inorganic nitrate supplementation improves the blood flow limitation and exaggerated pressor response to moderate-intensity forearm exercise in PAD.
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Affiliation(s)
- Nicholas T Kruse
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa.,Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Kenichi Ueda
- Department of Anesthesia, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - William E Hughes
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Darren P Casey
- Department of Physical Therapy and Rehabilitation Science, Carver College of Medicine, University of Iowa , Iowa City, Iowa.,Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa , Iowa City, Iowa.,Fraternal Order of Eagles Diabetes Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
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Nybäck L, Glännerud C, Larsson G, Weitzberg E, Shannon OM, McGawley K. Physiological and performance effects of nitrate supplementation during roller-skiing in normoxia and normobaric hypoxia. Nitric Oxide 2017; 70:1-8. [DOI: 10.1016/j.niox.2017.08.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 07/31/2017] [Accepted: 08/02/2017] [Indexed: 11/29/2022]
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Henni S, Abraham P. Muscle Oxygen content at exercise in patients with claudication. J Appl Physiol (1985) 2017; 123:1412. [PMID: 29167203 DOI: 10.1152/japplphysiol.00639.2017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 07/18/2017] [Accepted: 08/08/2017] [Indexed: 11/22/2022] Open
Affiliation(s)
- Samir Henni
- Department of Physiology and Functional Investigations, University Hospital, Angers, France; and .,UMR INSERM 1083 CNRS 6015, UFR santé, Reculée, Angers, France
| | - Pierre Abraham
- Department of Physiology and Functional Investigations, University Hospital, Angers, France; and.,UMR INSERM 1083 CNRS 6015, UFR santé, Reculée, Angers, France
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Kempf EA, Rollins KS, Hopkins TD, Butenas AL, Santin JM, Smith JR, Copp SW. Chronic femoral artery ligation exaggerates the pressor and sympathetic nerve responses during dynamic skeletal muscle stretch in decerebrate rats. Am J Physiol Heart Circ Physiol 2017; 314:H246-H254. [PMID: 29054973 DOI: 10.1152/ajpheart.00498.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mechanical and metabolic signals arising during skeletal muscle contraction reflexly increase sympathetic nerve activity and blood pressure (i.e., the exercise pressor reflex). In a rat model of simulated peripheral artery disease in which a femoral artery is chronically (~72 h) ligated, the mechanically sensitive component of the exercise pressor reflex during 1-Hz dynamic contraction is exaggerated compared with that found in normal rats. Whether this is due to an enhanced acute sensitization of mechanoreceptors by metabolites produced during contraction or involves a chronic sensitization of mechanoreceptors is unknown. To investigate this issue, in decerebrate, unanesthetized rats, we tested the hypothesis that the increases in mean arterial blood pressure and renal sympathetic nerve activity during 1-Hz dynamic stretch are larger when evoked from a previously "ligated" hindlimb compared with those evoked from the contralateral "freely perfused" hindlimb. Dynamic stretch provided a mechanical stimulus in the absence of contraction-induced metabolite production that closely replicated the pattern of the mechanical stimulus present during dynamic contraction. We found that the increases in mean arterial blood pressure (freely perfused: 14 ± 1 and ligated: 23 ± 3 mmHg, P = 0.02) and renal sympathetic nerve activity were significantly greater during dynamic stretch of the ligated hindlimb compared with the increases during dynamic stretch of the freely perfused hindlimb. These findings suggest that the exaggerated mechanically sensitive component of the exercise pressor reflex found during dynamic muscle contraction in this rat model of simulated peripheral artery disease involves a chronic sensitizing effect of ligation on muscle mechanoreceptors and cannot be attributed solely to acute contraction-induced metabolite sensitization. NEW & NOTEWORTHY We found that the pressor and sympathetic nerve responses during dynamic stretch were exaggerated in rats with a ligated femoral artery (a model of peripheral artery disease). Our findings provide mechanistic insights into the exaggerated exercise pressor reflex in this model and may have important implications for peripheral artery disease patients.
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Affiliation(s)
- Evan A Kempf
- Department of Kinesiology, Kansas State University , Manhattan, Kansas
| | - Korynne S Rollins
- Department of Kinesiology, Kansas State University , Manhattan, Kansas
| | - Tyler D Hopkins
- Department of Kinesiology, Kansas State University , Manhattan, Kansas
| | - Alec L Butenas
- Department of Kinesiology, Kansas State University , Manhattan, Kansas
| | - Joseph M Santin
- Division of Biological Sciences, University of Missouri , Columbia, Missouri
| | - Joshua R Smith
- Department of Kinesiology, Kansas State University , Manhattan, Kansas
| | - Steven W Copp
- Department of Kinesiology, Kansas State University , Manhattan, Kansas
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