1
|
Martin ZT, Shah AJ, Ko YA, Sheikh SAA, Daaboul O, Haddad G, Goldberg J, Smith NL, Lewis TT, Quyyumi AA, Bremner JD, Vaccarino V. Exaggerated Peripheral and Systemic Vasoconstriction During Trauma Recall in Posttraumatic Stress Disorder: A Co-Twin Control Study. Biol Psychiatry 2024; 96:278-286. [PMID: 38142719 PMCID: PMC11192861 DOI: 10.1016/j.biopsych.2023.12.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/23/2023] [Accepted: 12/14/2023] [Indexed: 12/26/2023]
Abstract
BACKGROUND Individuals with posttraumatic stress disorder (PTSD) face an increased risk of cardiovascular disease, but the mechanisms linking PTSD to cardiovascular disease remain incompletely understood. We used a co-twin control study design to test the hypothesis that individuals with PTSD exhibit augmented peripheral and systemic vasoconstriction during a personalized trauma recall task. METHODS In 179 older male twins from the Vietnam Era Twin Registry, lifetime history of PTSD and current (last month) PTSD symptoms were assessed. Participants listened to neutral and personalized trauma scripts while peripheral vascular tone (Peripheral Arterial Tone ratio) and systemic vascular tone (e.g., total vascular conductance) were measured. Linear mixed-effect models were used to assess the within-pair relationship between PTSD and vascular tone indices. RESULTS The mean age of participants was 68 years, and 19% had a history of PTSD. For the Peripheral Arterial Tone ratio analysis, 32 twins were discordant for a history of PTSD, and 46 were discordant for current PTSD symptoms. Compared with their brothers without PTSD, during trauma recall, participants with a history of PTSD had greater increases in peripheral (β = -1.01, 95% CI [-1.72, -0.30]) and systemic (total vascular conductance: β = -1.12, 95% CI [-1.97, -0.27]) vasoconstriction after adjusting for cardiovascular risk factors. Associations persisted after adjusting for antidepressant medication use and heart rate and blood pressure during the tasks. Analysis of current PTSD symptom severity showed consistent results. CONCLUSIONS PTSD is associated with exaggerated peripheral and systemic vasoconstrictor responses to traumatic stress reminders, which may contribute to elevated risk of cardiovascular disease.
Collapse
Affiliation(s)
- Zachary T Martin
- Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Amit J Shah
- Rollins School of Public Health, Emory University, Atlanta, Georgia; Emory University School of Medicine, Emory University, Atlanta, Georgia; Joseph Maxwell Cleland Atlanta VA Medical Center, Decatur, Georgia
| | - Yi-An Ko
- Rollins School of Public Health, Emory University, Atlanta, Georgia
| | | | - Obada Daaboul
- Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - George Haddad
- Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Jack Goldberg
- Seattle Epidemiologic Research and Information Center, U.S. Department of Veterans Affairs Office of Research and Development, Seattle, Washington
| | - Nicholas L Smith
- Seattle Epidemiologic Research and Information Center, U.S. Department of Veterans Affairs Office of Research and Development, Seattle, Washington
| | - Tené T Lewis
- Rollins School of Public Health, Emory University, Atlanta, Georgia
| | - Arshed A Quyyumi
- Emory University School of Medicine, Emory University, Atlanta, Georgia
| | - J Douglas Bremner
- Emory University School of Medicine, Emory University, Atlanta, Georgia; Joseph Maxwell Cleland Atlanta VA Medical Center, Decatur, Georgia
| | - Viola Vaccarino
- Rollins School of Public Health, Emory University, Atlanta, Georgia; Emory University School of Medicine, Emory University, Atlanta, Georgia.
| |
Collapse
|
2
|
Shiozawa K, Saito M, Lee JB, Seo N, Kondo H, Kashima H, Endo MY, Ishida K, Millar PJ, Katayama K. Aging in females has minimal effect on changes in celiac artery blood flow during dynamic light-intensity exercise. Am J Physiol Regul Integr Comp Physiol 2024; 327:R14-R24. [PMID: 38738294 DOI: 10.1152/ajpregu.00012.2024] [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: 01/16/2024] [Revised: 04/30/2024] [Accepted: 05/02/2024] [Indexed: 05/14/2024]
Abstract
Blood flow to the active muscles and arterial blood pressure (ABP) increase during dynamic exercise, whereas blood flow to inactive organs (e.g., splanchnic organs and inactive limbs) declines. Aging leads to exaggerated ABP responses to exercise in females, but whether this is related to greater splanchnic vasoconstriction is unknown. This study sought to clarify the effect of aging in females on celiac artery blood flow during dynamic light-intensity exercise. Twelve healthy young females (YF: 20 ± 2 yr, mean ± SD) and 12 healthy older females (OF: 71 ± 4 yr) performed dynamic knee-extension and knee-flexion exercises at 30% of heart rate reserve for 4 min. The absolute changes from baseline (Δ) for mean arterial blood pressure (MAP), celiac artery mean blood flow (celMBF), and celiac vascular conductance (celVC) during exercise were calculated. ABP was measured using an automated sphygmomanometer, and celMBF was recorded by Doppler ultrasonography. The increase in MAP during exercise was greater in OF than in YF (YF: +14 ± 7 mmHg, OF: +24 ± 13 mmHg, P = 0.028). The celMBF decreased during exercise in both groups, but there was no significant difference in the response between YF and OF (YF: -93.0 ± 66.1 mL/min, OF: -89.6 ± 64.0 mL/min, P = 0.951). The celVC also decreased during exercise and remained lower than baseline during exercise. However, the response was not different between YF and OF (YF: -1.8 ± 1.0 mL/min/mmHg, OF: -1.5 ± 0.6 mL/min/mmHg, P = 0.517). These results demonstrate that aging in females has minimal influence on splanchnic artery hemodynamic responses during dynamic light-intensity exercise, suggesting that exaggerated ABP responses during exercise in OF are not due to greater splanchnic vasoconstriction.NEW & NOTEWORTHY During exercise, the splanchnic arteries vasoconstrict, contributing to blood flow redistribution and the blood pressure response. Blood pressure responses to exercise are exaggerated with aging in females; however, the physiological mechanism responsible has not been clarified. We show that celiac artery blood flow changes during light-intensity dynamic exercise do not differ with age in females. This indicates the exaggerated blood pressure to exercise with aging is likely not due to a difference in splanchnic vasoconstriction.
Collapse
Affiliation(s)
- Kana Shiozawa
- Graduate School of Medicine, Nagoya University, Nagoya, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Mitsuru Saito
- Applied Physiology Laboratory, Toyota Technological Institute, Nagoya, Japan
| | - Jordan B Lee
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Natsuki Seo
- Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Haruna Kondo
- Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Hideaki Kashima
- Department of Health Science, Prefectural University of Hiroshima, Hiroshima, Japan
| | - Masako Yamaoka Endo
- Department of Health Science, Prefectural University of Hiroshima, Hiroshima, Japan
| | - Koji Ishida
- Graduate School of Medicine, Nagoya University, Nagoya, Japan
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
| | - Philip J Millar
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Keisho Katayama
- Graduate School of Medicine, Nagoya University, Nagoya, Japan
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
| |
Collapse
|
3
|
Vikström A, Holmlund P, Holmgren M, Wåhlin A, Zarrinkoob L, Malm J, Eklund A. Establishing the distribution of cerebrovascular resistance using computational fluid dynamics and 4D flow MRI. Sci Rep 2024; 14:14585. [PMID: 38918589 PMCID: PMC11199643 DOI: 10.1038/s41598-024-65431-4] [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: 01/26/2024] [Accepted: 06/20/2024] [Indexed: 06/27/2024] Open
Abstract
Cerebrovascular resistance (CVR) regulates blood flow in the brain, but little is known about the vascular resistances of the individual cerebral territories. We present a method to calculate these resistances and investigate how CVR varies in the hemodynamically disturbed brain. We included 48 patients with stroke/TIA (29 with symptomatic carotid stenosis). By combining flow rate (4D flow MRI) and structural computed tomography angiography (CTA) data with computational fluid dynamics (CFD) we computed the perfusion pressures out from the circle of Willis, with which CVR of the MCA, ACA, and PCA territories was estimated. 56 controls were included for comparison of total CVR (tCVR). CVR were 33.8 ± 10.5, 59.0 ± 30.6, and 77.8 ± 21.3 mmHg s/ml for the MCA, ACA, and PCA territories. We found no differences in tCVR between patients, 9.3 ± 1.9 mmHg s/ml, and controls, 9.3 ± 2.0 mmHg s/ml (p = 0.88), nor in territorial CVR in the carotid stenosis patients between ipsilateral and contralateral hemispheres. Territorial resistance associated inversely to territorial brain volume (p < 0.001). These resistances may work as reference values when modelling blood flow in the circle of Willis, and the method can be used when there is need for subject-specific analysis.
Collapse
Affiliation(s)
- Axel Vikström
- Department of Diagnostics and Intervention, Biomedical Engineering and Radiation Physics, Umeå University, 901 87, Umeå, Sweden.
| | - Petter Holmlund
- Department of Diagnostics and Intervention, Biomedical Engineering and Radiation Physics, Umeå University, 901 87, Umeå, Sweden
- Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden
| | - Madelene Holmgren
- Department of Diagnostics and Intervention, Biomedical Engineering and Radiation Physics, Umeå University, 901 87, Umeå, Sweden
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Wåhlin
- Department of Diagnostics and Intervention, Biomedical Engineering and Radiation Physics, Umeå University, 901 87, Umeå, Sweden
- Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
- Department of Applied Physics and Electronics, Umeå University, Umeå, Sweden
| | - Laleh Zarrinkoob
- Department of Diagnostics and Intervention, Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden
| | - Jan Malm
- Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden
| | - Anders Eklund
- Department of Diagnostics and Intervention, Biomedical Engineering and Radiation Physics, Umeå University, 901 87, Umeå, Sweden
- Umeå Center for Functional Brain Imaging, Umeå University, Umeå, Sweden
| |
Collapse
|
4
|
Gentilin A, Cevese A, Tam E. Postexercise cardiovascular hemodynamics assessment before and after a 30-minute standing still recovery. J Sports Med Phys Fitness 2024; 64:201-210. [PMID: 37791829 DOI: 10.23736/s0022-4707.23.15330-8] [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: 10/05/2023]
Abstract
BACKGROUND Although postexercise syncope usually occurs shortly after physical exercise conclusion, athletes commonly reveal symptoms of postexercise hypotension several tens of minutes after exercise completion. Currently, no studies have investigated central hemodynamic regulation during posture changes occurring several tens of minutes after exercise compared to immediately after cessation. METHODS This study examined changes in mean arterial pressure (MAP), heart rate (HR), systemic vascular conductance (SVC), cardiac output, and stroke volume during two sets of tilt tests performed before vs. after a 30-minute standing still recovery, respectively. Tilt tests were performed after a short-lasting supramaximal test (WNG) and long-lasting maximal incremental test (INC) in 12 young endurance-trained individuals. RESULTS The key findings were that, regardless of the exercise type, the 30-minute recovery augmented (P<0.01) the increase in HR and the drop in SVC during the transition from supine to upright, although the MAP drop was similar (P=0.99) after vs. before recovery. INC led to greater increases (P<0.01) in HR and drops (P<0.01) in SVC compared to WNG during postural transitions both before and after the recovery. CONCLUSIONS These findings suggest that, in a population that tolerates postexercise hypotension, MAP neural control is more challenged after a 30-minute standing still recovery than before, as evidenced by an augmented vasodilation capacity along with an increased HR buffering response during posture changes. Moreover, our data suggest that effective MAP control is resulting from an equally effective HR buffering response on MAP. Therefore, exercises that induce greater systemic vasodilation lead to greater HR buffering responses.
Collapse
Affiliation(s)
| | - Antonio Cevese
- Department of Neuroscience, Biomedicine, and Movement Sciences, University of Verona, Verona, Italy
| | - Enrico Tam
- Department of Neuroscience, Biomedicine, and Movement Sciences, University of Verona, Verona, Italy
| |
Collapse
|
5
|
Gondim ML, Rocha HNM, Mira PAC, Nobrega ACL, Prodel E. Effects of alpha-adrenergic receptor blockade on coronary circulation in postmenopausal women. Eur J Appl Physiol 2023; 123:2779-2790. [PMID: 37368136 DOI: 10.1007/s00421-023-05267-4] [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: 01/31/2023] [Accepted: 06/19/2023] [Indexed: 06/28/2023]
Abstract
We sought to investigate the effect of the α1-adrenergic receptor blockade during handgrip exercise (Grip), isolated metaboreflex activation (Metabo), and cold pressor test (CPT) on coronary circulation in young (YW) and postmenopausal women (PMW). Ten YW and 9 PMW underwent two protocols: (1) 3 min of baseline followed by 3 min of CPT and (2) 3 min of rest, 3 min of Grip followed by 3 min of Metabo. Protocols were carried out under control conditions and α1-adrenergic receptor blockade (oral prazosin 0.03 mg·kg-1). Coronary blood velocity (CBV) and vascular conductance (CCI) were lower in PMW. Grip increased CBV only in YW (YW: Δ18.0 ± 21.1% vs. PMW: Δ4.2 ± 10.1%; p < 0.05), and the blockade did not change the CBV response to Grip in YW and PMW. During the Metabo, CBV returned to resting levels in YW and was unchanged from rest in PMW, before (YW:Δ1.7 ± 8.7% vs. PMW: Δ- 1.5 ± 8.6) and under the blockade (YW: Δ4.5 ± 14.8% vs. PMW: Δ9.1 ± 29.5%). CPT did not change CBV in both groups (YW: Δ3.9 ± 8.0 vs. PMW: Δ- 4.1 ± 6.2%), following the α1-blockade, CPT increased CBV only in YW (YW: Δ11.2 ± 12.8% vs. PMW: Δ2.2 ± 7.1%; p < 0.05 for group and condition). CCI decreased during Grip, Metabo, and CPT in YW and PMW, while the blockade prevented that decrease only in YW. The α1-adrenergic receptor plays a role in the control of coronary circulation in young women, evoking stronger vasoconstriction during CPT than Grip and Metabo in YW. PMW have impaired vasomotor control in the coronary circulation, which seems not to be caused by the α1-adrenergic receptor.
Collapse
Affiliation(s)
- Maitê L Gondim
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil
| | - Helena N M Rocha
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil
- Laboratory of Integrative Cardiometabology, Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil
| | - Pedro A C Mira
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil
| | - Antonio C L Nobrega
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil
| | - Eliza Prodel
- Laboratory of Exercise Science, Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Brazil.
| |
Collapse
|
6
|
Lammers J, Al-Malak M, Kopparthy V, Figueroa BA, Rampazzo A, Bassiri Gharb B. Letter Regarding: Continuous Versus Pulsatile Flow in 24-Hour Vascularized Composite Allograft Machine Perfusion in Swine: A Pilot Study. J Surg Res 2023; 291:749-750. [PMID: 37394332 DOI: 10.1016/j.jss.2023.04.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 07/04/2023]
Affiliation(s)
- Jacob Lammers
- Department of Plastic and Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Mazen Al-Malak
- Department of Plastic and Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Varun Kopparthy
- Department of Plastic and Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Brian A Figueroa
- Department of Plastic and Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Antonio Rampazzo
- Department of Plastic and Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Bahar Bassiri Gharb
- Department of Plastic and Reconstructive Surgery, Cleveland Clinic Foundation, Cleveland, Ohio.
| |
Collapse
|
7
|
D'Souza AW, Hissen SL, Manabe K, Washio T, Annis MC, Sanchez B, Fu Q, Shoemaker JK. Effects of biological sex and oral contraception on the sympathetic neurocirculatory adjustments to static handgrip exercise in humans. Am J Physiol Regul Integr Comp Physiol 2023; 325:R629-R644. [PMID: 37694305 DOI: 10.1152/ajpregu.00147.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/14/2023] [Accepted: 09/02/2023] [Indexed: 09/12/2023]
Abstract
While biological sex affects the neurocirculatory adjustments to exercise, the effects of sex hormones on sympathetic action potential (AP) patterns and ensuing vascular transduction remain unknown. We tested the hypothesis that males, and females using oral contraceptive pills (OCPs), would demonstrate larger increases in sympathetic activation and sympathetic vascular transduction compared with naturally menstruating females during static handgrip exercise (SHG) and postexercise circulatory occlusion (PECO). Young males [n = 14, 25 (5) yr], females using OCPs [n = 16, 24 (6) yr], and naturally menstruating females [n = 18, 26 (4) yr] underwent assessments of multiunit muscle sympathetic nerve activity (MSNA)/AP discharge patterns (microneurography) and femoral artery blood flow (ultrasound) during fatiguing SHG at 40% maximum voluntary contraction and 2-min PECO. Sympathetic vascular transduction was determined as the quotient of the change in leg vascular conductance (LVC) and MSNA/AP discharge. Males demonstrated greater increases in APs/burst [males: Δ7 (6) vs. midluteal: Δ2 (3), P = 0.028] and total AP clusters [males: Δ5 (3) vs. midluteal: Δ2 (3), P = 0.008] compared with naturally menstruating females only but not those using OCPs during exercise (APs/burst: P = 0.171, total clusters: P = 0.455). Sympathetic vascular transduction of MSNA burst amplitude, APs/burst, and total AP clusters was greater in males and females using OCPs compared with naturally menstruating females (range: P = 0.004-0.044). In contrast, during PECO no group differences were observed in AP discharge (range: P = 0.510-0.872), and AP discharge was not related to LVC during PECO (range: P = 0.08-0.949). These data indicate that biological sex and OCP use impact the central generation of AP discharge, as well as the transduction of these neuronal messages into peripheral vasoconstriction during static exercise.
Collapse
Affiliation(s)
- Andrew W D'Souza
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, Ontario, Canada
- Women's Heart Health Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Sarah L Hissen
- Women's Heart Health Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Kazumasa Manabe
- Women's Heart Health Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Takuro Washio
- Women's Heart Health Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Meghan C Annis
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, Ontario, Canada
| | - Belinda Sanchez
- Women's Heart Health Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Qi Fu
- Women's Heart Health Laboratory, Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - J Kevin Shoemaker
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, Ontario, Canada
- Department of Physiology and Pharmacology, Western University, London, Ontario, Canada
| |
Collapse
|
8
|
D'Souza AW, Hissen SL, Manabe K, Takeda R, Washio T, Coombs GB, Sanchez B, Fu Q, Shoemaker JK. Age- and sex-related differences in sympathetic vascular transduction and neurohemodynamic balance in humans. Am J Physiol Heart Circ Physiol 2023; 325:H917-H932. [PMID: 37594483 DOI: 10.1152/ajpheart.00301.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/14/2023] [Accepted: 08/15/2023] [Indexed: 08/19/2023]
Abstract
Bursts of muscle sympathetic nerve activity (MSNA) and the ensuing vasoconstriction are pivotal determinants of beat-by-beat blood pressure regulation. Although age and sex impact blood pressure regulation, how these factors affect the central and peripheral arcs of the baroreflex remains unclear. In 27 young [25 (SD 3) yr] males (YM; n = 14) and females (YF; n = 13) and 23 older [71 (SD 5) yr] males (OM; n = 11) and females (OF; n = 12), femoral artery blood flow, blood pressure, and MSNA were recorded for 10 min of supine rest. Sympathetic baroreflex sensitivity (i.e., central arc) was quantified as the relationship between diastolic blood pressure and MSNA burst incidence. Signal averaging was used to determine sympathetic vascular transduction into leg vascular conductance (LVC) for 12 cardiac cycles following MSNA bursts (i.e., peripheral arc). Older adults demonstrated attenuated sympathetic transduction into LVC (both P < 0.001) following MSNA bursts, and smaller increases in sympathetic transduction as a function of MSNA burst size and firing pattern compared with young adults (range, P = 0.004-0.032). YM (r2 = 0.36; P = 0.032) and OM (r2 = 0.51; P = 0.014) exhibited an inverse relationship between the central and peripheral arcs of the baroreflex, whereas females did not (YF, r2 = 0.03, P = 0.621; OF, r2 = 0.06, P = 0.445). MSNA burst incidence was inversely related to sympathetic transduction in YM and OF (range, P = 0.03-0.046) but not in YF or OM (range, P = 0.360-0.603). These data indicate that age is associated with attenuated sympathetic vascular transduction, whereas age- and sex-specific changes are present in the relationship between the central and peripheral arcs of the baroreflex regulation of blood pressure.NEW & NOTEWORTHY Sympathetic vascular transduction is attenuated in older compared with young adults, regardless of biological sex. Males, but not females (regardless of age), demonstrate an inverse relationship between central (sympathetic baroreflex sensitivity) and peripheral (sympathetic vascular transduction) components of the baroreflex arc. Young males and older females exhibit an inverse relationship between resting sympathetic outflow and sympathetic vascular transduction. Our results indicate that age and sex exert independent and interactive effects on sympathetic vascular transduction and sympathetic neurohemodynamic balance in humans.
Collapse
Affiliation(s)
- Andrew W D'Souza
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, Ontario, Canada
| | - Sarah L Hissen
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Kazumasa Manabe
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Ryosuke Takeda
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Laboratory of Neuromuscular Biomechanics, School of Health and Sport Sciences, Chukyo University, Toyota, Japan
| | - Takuro Washio
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Geoff B Coombs
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, Ontario, Canada
| | - Belinda Sanchez
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Qi Fu
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, Texas, United States
- Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - J Kevin Shoemaker
- Neurovascular Research Laboratory, School of Kinesiology, Western University, London, Ontario, Canada
- Department of Physiology and Pharmacology, Western University, London, Ontario, Canada
| |
Collapse
|
9
|
Simpson LL, Hansen AB, Moralez G, Amin SB, Hofstaetter F, Gasho C, Stembridge M, Dawkins TG, Tymko MM, Ainslie PN, Lawley JS, Hearon CM. Adrenergic control of skeletal muscle blood flow during chronic hypoxia in healthy males. Am J Physiol Regul Integr Comp Physiol 2023; 324:R457-R469. [PMID: 36717165 PMCID: PMC10026988 DOI: 10.1152/ajpregu.00230.2022] [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: 09/19/2022] [Revised: 01/24/2023] [Accepted: 01/24/2023] [Indexed: 02/01/2023]
Abstract
Sympathetic transduction is reduced following chronic high-altitude (HA) exposure; however, vascular α-adrenergic signaling, the primary mechanism mediating sympathetic vasoconstriction at sea level (SL), has not been examined at HA. In nine male lowlanders, we measured forearm blood flow (Doppler ultrasound) and calculated changes in vascular conductance (ΔFVC) during 1) incremental intra-arterial infusion of phenylephrine to assess α1-adrenergic receptor responsiveness and 2) combined intra-arterial infusion of β-adrenergic and α-adrenergic antagonists propranolol and phentolamine (α-β-blockade) to assess adrenergic vascular restraint at rest and during exercise-induced sympathoexcitation (cycling; 60% peak power). Experiments were performed near SL (344 m) and after 3 wk at HA (4,383 m). HA abolished the vasoconstrictor response to low-dose phenylephrine (ΔFVC: SL: -34 ± 15%, vs. HA; +3 ± 18%; P < 0.0001) and markedly attenuated the response to medium (ΔFVC: SL: -45 ± 18% vs. HA: -28 ± 11%; P = 0.009) and high (ΔFVC: SL: -47 ± 20%, vs. HA: -35 ± 20%; P = 0.041) doses. Blockade of β-adrenergic receptors alone had no effect on resting FVC (P = 0.500) and combined α-β-blockade induced a similar vasodilatory response at SL and HA (P = 0.580). Forearm vasoconstriction during cycling was not different at SL and HA (P = 0.999). Interestingly, cycling-induced forearm vasoconstriction was attenuated by α-β-blockade at SL (ΔFVC: Control: -27 ± 128 vs. α-β-blockade: +19 ± 23%; P = 0.0004), but unaffected at HA (ΔFVC: Control: -20 ± 22 vs. α-β-blockade: -23 ± 11%; P = 0.999). Our results indicate that in healthy males, altitude acclimatization attenuates α1-adrenergic receptor responsiveness; however, resting α-adrenergic restraint remains intact, due to concurrent resting sympathoexcitation. Furthermore, forearm vasoconstrictor responses to cycling are preserved, although the contribution of adrenergic receptors is diminished, indicating a reliance on alternative vasoconstrictor mechanisms.
Collapse
Affiliation(s)
- Lydia L Simpson
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Alexander B Hansen
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Gilbert Moralez
- Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, United States
| | - Sachin B Amin
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Florian Hofstaetter
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
| | - Christopher Gasho
- Department of Medicine, Division of Pulmonary and Critical Care, Loma Linda University, Loma Linda, California, United States
| | - Mike Stembridge
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, Wales, United Kingdom
| | - Tony G Dawkins
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Michael M Tymko
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
- Faculty of Kinesiology, Sport, and Recreation, University of Alberta, Edmonton, Alberta, Canada
- Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Philip N Ainslie
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Justin S Lawley
- Department of Sport Science, Division of Performance Physiology and Prevention, Universität Innsbruck, Innsbruck, Austria
- Institute of Mountain Emergency Medicine, Eurac Research, Bolzano, Italy
| | - Christopher M Hearon
- Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, United States
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Dallas, Dallas, Texas, United States
| |
Collapse
|
10
|
Sluyter R, Sophocleous RA, Stokes L. P2X receptors: Insights from the study of the domestic dog. Neuropharmacology 2023; 224:109358. [PMID: 36464207 DOI: 10.1016/j.neuropharm.2022.109358] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 11/23/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022]
Abstract
Fifty years ago, the late Geoffrey Burnstock described the concept of purinergic nerves and transmission bringing into existence the broader concepts of purinergic signaling including P2X receptors. These receptors are trimeric ligand-gated cation channels activated by extracellular adenosine 5'-triphosphate (ATP). P2X receptors have important roles in health and disease and continue to gain interest as potential therapeutic targets in inflammatory, neurological, cardiovascular and many other disorders including cancer. Current understanding of P2X receptors has largely arisen from the study of these receptors in humans and rodents, but additional insights have been obtained from the study of P2X receptors in the domestic dog, Canis familiaris. This review article will briefly introduce purinergic signaling and P2X receptors, before detailing the pharmacological profiles of the two recombinant canine P2X receptors studied to date, P2X7 and P2X4. The article will then describe the current state of knowledge concerning the distribution and function of the P2X receptor family in dogs. The article will also discuss the characterization of single nucleotide polymorphisms in the canine P2RX7 gene, and contrast this variation to the canine P2RX4 gene, which is largely conserved between dogs. Finally, this article will outline published examples of the use of dogs to study the pharmacokinetics of P2X7 and P2X3 antagonists, and how they have contributed to the preclinical testing of antagonists to human P2X7, CE-224,535, and human P2X3, Gefapixant (AF-219, MK-7264) and Eliapixant (BAY, 1817080), with Gefapixant gaining recent approval for use in the treatment of refractory chronic cough in humans. This article is part of the Special Issue on 'Purinergic Signaling: 50 years'.
Collapse
Affiliation(s)
- Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia.
| | - Reece A Sophocleous
- Illawarra Health and Medical Research Institute, Wollongong, NSW, 2522, Australia; Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Leanne Stokes
- School of Pharmacy, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK
| |
Collapse
|
11
|
Skow RJ, Brothers RM, Claassen JAHR, Day TA, Rickards CA, Smirl JD, Brassard P. On the use and misuse of cerebral hemodynamics terminology using Transcranial Doppler ultrasound: a call for standardization. Am J Physiol Heart Circ Physiol 2022; 323:H350-H357. [PMID: 35839156 DOI: 10.1152/ajpheart.00107.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cerebral hemodynamics (e.g., cerebral blood flow) can be measured and quantified using many different methods, with Transcranial Doppler ultrasound (TCD) being one of the most commonly utilized approaches. In human physiology, the terminology used to describe metrics of cerebral hemodynamics are inconsistent, and in some instances technically inaccurate; this is especially true when evaluating, reporting, and interpreting measures from TCD. Therefore, this perspectives article presents recommended terminology when reporting cerebral hemodynamic data. We discuss the current use and misuse of the terminology in the context of using TCD to measure and quantify cerebral hemodynamics and present our rationale and consensus on the terminology that we recommend moving forward. For example, one recommendation is to discontinue use of the term "cerebral blood flow velocity" in favor of "cerebral blood velocity" with precise indication of the vessel of interest. We also recommend clarity when differentiating between discrete cerebrovascular regulatory mechanisms, namely cerebral autoregulation, neurovascular coupling, and cerebrovascular reactivity. This will be a useful guide for investigators in the field of cerebral hemodynamics research.
Collapse
Affiliation(s)
- Rachel J Skow
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, United States
| | - R Matthew Brothers
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, United States
| | - Jurgen A H R Claassen
- Department of Geriatrics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Trevor A Day
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, Alberta, Canada
| | - Caroline A Rickards
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Jonathan D Smirl
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Canada
| |
Collapse
|
12
|
Kawasaki A, Hayashi N. Playing a musical instrument increases blood flow in the middle cerebral artery. PLoS One 2022; 17:e0269679. [PMID: 35675278 PMCID: PMC9176837 DOI: 10.1371/journal.pone.0269679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 05/25/2022] [Indexed: 11/18/2022] Open
Abstract
Purpose Studies using functional magnetic resonance imaging and positron-emission tomography suggest that many regions of the brain are activated by such complex muscle activity. Although these studies demonstrated relative increases in blood flow in some brain regions with increased neural activity, whether or not the absolute value of cerebral blood flow increases has yet to be elucidated. It also remains unknown whether playing musical instruments affects cerebral blood flow. The aim of this study was to determine the impact of playing a musical instrument on blood flow velocity in the middle cerebral artery (MCAv) by using Doppler ultrasound to measure absolute values of arterial flow velocity. Methods Thirteen musicians performed three pieces of music with different levels of difficulty: play for the first time (FS), music in practice (PR) and already mastered (MS) on either piano or violin. MCAv was recorded continuously from 10 min before until 10 min after playing. Associations between the cerebral blood flow response and blood pressure and gas-exchange variables were examined. Results PR and MS significantly increased the MCAv. The blood pressure increased significantly in performances of all difficulty levels except for MS. There were no significant changes in exhaled gas variables during the performance. Conclusion These findings suggest that playing a musical instrument increases MCAv, and that this change is influenced by the difficulty of the performance.
Collapse
Affiliation(s)
- Ai Kawasaki
- Department of Social and Human Sciences, Tokyo Institute of Technology, Tokyo, Japan
| | - Naoyuki Hayashi
- Department of Social and Human Sciences, Tokyo Institute of Technology, Tokyo, Japan.,Faculty of Sport Sciences, Waseda University, Saitama, Japan
| |
Collapse
|
13
|
Urroz Lopez M, Mitchell JR, Sheldon RS, Tyberg JV. Effector mechanisms in the baroreceptor control of blood pressure. ADVANCES IN PHYSIOLOGY EDUCATION 2022; 46:282-285. [PMID: 35201919 DOI: 10.1152/advan.00160.2021] [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: 10/04/2021] [Revised: 01/31/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
While the effects of changing heart rate and systemic vascular resistance have been generally understood and appreciated, the effects of changes in left ventricular contractility on end-systolic volume may have been less understood and appreciated and the effects of changes in venous capacitance on end-diastolic volume may have been unknown to many readers. Herein, we have provided a brief review for the medical student and beginning graduate student highlighting these sometimes-complex relationships.
Collapse
Affiliation(s)
- Maryell Urroz Lopez
- Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada
- Department of Cardiac Sciences, Cumming School of Medicine, Calgary, Alberta, Canada
| | - Jamie R Mitchell
- Faculty of Medicine and Dentistry, Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
| | - Robert S Sheldon
- Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada
- Department of Cardiac Sciences, Cumming School of Medicine, Calgary, Alberta, Canada
| | - John V Tyberg
- Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada
- Physiology/Pharmacology, Cumming School of Medicine, Calgary, Alberta, Canada
| |
Collapse
|
14
|
Hansen AB, Amin SB, Hofstätter F, Mugele H, Simpson LL, Gasho C, Dawkins TG, Tymko MM, Ainslie PN, Villafuerte FC, Hearon CM, Lawley JS, Moralez G. Global Reach 2018: sympathetic neural and hemodynamic responses to submaximal exercise in Andeans with and without chronic mountain sickness. Am J Physiol Heart Circ Physiol 2022; 322:H844-H856. [PMID: 35333117 PMCID: PMC9018046 DOI: 10.1152/ajpheart.00555.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 03/14/2022] [Accepted: 03/14/2022] [Indexed: 11/22/2022]
Abstract
Andeans with chronic mountain sickness (CMS) and polycythemia have similar maximal oxygen uptakes to healthy Andeans. Therefore, this study aimed to explore potential adaptations in convective oxygen transport, with a specific focus on sympathetically mediated vasoconstriction of nonactive skeletal muscle. In Andeans with (CMS+, n = 7) and without (CMS-, n = 9) CMS, we measured components of convective oxygen delivery, hemodynamic (arterial blood pressure via intra-arterial catheter), and autonomic responses [muscle sympathetic nerve activity (MSNA)] at rest and during steady-state submaximal cycling exercise [30% and 60% peak power output (PPO) for 5 min each]. Cycling caused similar increases in heart rate, cardiac output, and oxygen delivery at both workloads between both Andean groups. However, at 60% PPO, CMS+ had a blunted reduction in Δtotal peripheral resistance (CMS-, -10.7 ± 3.8 vs. CMS+, -4.9 ± 4.1 mmHg·L-1·min-1; P = 0.012; d = 1.5) that coincided with a greater Δforearm vasoconstriction (CMS-, -0.2 ± 0.6 vs. CMS+, 1.5 ± 1.3 mmHg·mL-1·min-1; P = 0.008; d = 1.7) and a rise in Δdiastolic blood pressure (CMS-, 14.2 ± 7.2 vs. CMS+, 21.6 ± 4.2 mmHg; P = 0.023; d = 1.2) compared with CMS-. Interestingly, although MSNA burst frequency did not change at 30% or 60% of PPO in either group, at 60% Δburst incidence was attenuated in CMS+ (P = 0.028; d = 1.4). These findings indicate that in Andeans with polycythemia, light intensity exercise elicited similar cardiovascular and autonomic responses compared with CMS-. Furthermore, convective oxygen delivery is maintained during moderate-intensity exercise despite higher peripheral resistance. In addition, the elevated peripheral resistance during exercise was not mediated by greater sympathetic neural outflow, thus other neural and/or nonneural factors are perhaps involved.NEW & NOTEWORTHY During submaximal exercise, convective oxygen transport is maintained in Andeans suffering from polycythemia. Light intensity exercise elicited similar cardiovascular and autonomic responses compared with healthy Andeans. However, during moderate-intensity exercise, we observed a blunted reduction in total peripheral resistance, which cannot be ascribed to an exaggerated increase in muscle sympathetic nerve activity, indicating possible contributions from other neural and/or nonneural mechanisms.
Collapse
Affiliation(s)
- Alexander B Hansen
- Division of Performance, Physiology and Prevention, Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Sachin B Amin
- Division of Performance, Physiology and Prevention, Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Florian Hofstätter
- Division of Performance, Physiology and Prevention, Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Hendrik Mugele
- Division of Performance, Physiology and Prevention, Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Lydia L Simpson
- Division of Performance, Physiology and Prevention, Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Christopher Gasho
- Division of Pulmonary and Critical Care, Department of Medicine, University of Loma Linda, Loma Linda, California
| | - Tony G Dawkins
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, United Kingdom
| | - Michael M Tymko
- Physical Activity and Diabetes Laboratory, Faculty of Kinesiology and Recreation, University of Alberta, Edmonton, Alberta, Canada
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Philip N Ainslie
- Centre of Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Francisco C Villafuerte
- Laboratorio de Fisiología Comparada/Fisiología del Transporte de Oxígeno Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Christopher M Hearon
- Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Dallas, Dallas, Texas
| | - Justin S Lawley
- Division of Performance, Physiology and Prevention, Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Gilbert Moralez
- Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
15
|
Lake SL, Guadagni V, Kendall KD, Chadder M, Anderson TJ, Leigh R, Rawling JM, Hogan DB, Hill MD, Poulin MJ. Aerobic exercise training in older men and women-Cerebrovascular responses to submaximal exercise: Results from the Brain in Motion study. Physiol Rep 2022; 10:e15158. [PMID: 35212167 PMCID: PMC8874289 DOI: 10.14814/phy2.15158] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 12/07/2021] [Indexed: 12/12/2022] Open
Abstract
Physical inactivity is a leading modifiable risk factor for cardiovascular and cerebrovascular disease, cognitive dysfunction, and global mortality. Regular exercise might mitigate age-related declines in cardiovascular and cerebrovascular function. In this study, we hypothesize that a 6-month aerobic exercise intervention will lead to a decrease in cerebrovascular resistance index (CVRi) and to an increase in cerebral blood flow (CBF) and cerebrovascular conductance index (CVCi) during two submaximal exercise workloads (40% VO2 max and 65 W), intensities that have been shown to be comparable to activities of daily life. Two hundred three low-active healthy men and women enrolled in the Brain in Motion study, completed a 6-month exercise intervention and underwent submaximal and maximal tests pre-/post-intervention. The intervention improved the gas exchange threshold and maximal oxygen consumption (VO2 max), with no change in heart rate at VO2 max, during the treadmill VO2 max test. Heart rate and CVRi decreased from pre-intervention values during both relative (40% VO2 max) and absolute (65 W) submaximal exercise tests. Blood flow velocity in the middle cerebral artery and CVCi increased post-intervention during 40% VO2 max and 65 W. Changes in mean arterial pressure were found only during the absolute component (65 W). Our study demonstrates that aerobic exercise improves not only cardiorespiratory indices but also cerebrovascular function at submaximal workloads which may help to mitigate age-related declines in everyday life. Investigation of the mechanisms underlying the decline in cardiovascular and cerebrovascular capacity with aging has important implications for the maintenance of health and continued independence of older adults.
Collapse
Affiliation(s)
- Sonja L Lake
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Clinical & Translational Exercise Physiology Lab, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Veronica Guadagni
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Karen D Kendall
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Clinical & Translational Exercise Physiology Lab, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Michaela Chadder
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Clinical & Translational Exercise Physiology Lab, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Todd J Anderson
- Department of Cardiac Sciences, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Richard Leigh
- Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jean M Rawling
- Department of Family Medicine, University of Calgary, Calgary, Alberta, Canada
| | - David B Hogan
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Division of Geriatric Medicine, Department of Medicine, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Michael D Hill
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Marc J Poulin
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Brenda Strafford Foundation Chair in Alzheimer Research, Calgary, Alberta, Canada
| |
Collapse
|
16
|
Boparai RS, Skow RJ, Farooq S, Steinback CD, Davenport MH. Prenatal exercise and cardiovascular health (PEACH) study: The remote effect of aerobic exercise training on conduit artery and resistance vessel function. Appl Physiol Nutr Metab 2021; 46:1459-1468. [PMID: 34161737 DOI: 10.1139/apnm-2020-0902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We assessed the impact of a structured lower-limb aerobic exercise training intervention during pregnancy on brachial artery endothelial function, shear rate and patterns, and forearm blood flow and reactive hyperemia. Twenty-seven pregnant women were recruited and randomized into either a control group (n=11; 31.0 ± 0.7 years), or an exercise intervention group (n=16; 32.6 ± 0.9 years; NCT02948439). The exercise group completed 40 minutes of aerobic exercise (50-70% heart rate reserve) 3-4 times per week, between the second and third trimester of pregnancy. Endothelial function was assessed using flow-mediated dilation (FMD, normalized for shear stress) pre- (16-20 weeks) and post-intervention (34-36 weeks). The exercise training group experienced an attenuated increase in mean arterial pressure (MAP) relative to the control group (∆MAP exercise: +2± 2 mmHg vs. control: +7±3 mmHg; p=0.044) from pre- to post-intervention. % FMD change corrected for shear stress was not different between groups (p=0.460); however, the post occlusion mean flow rate (exercise: 437±32 mL/min vs. control: 364±35 mL/min; p=0.001) and post occlusion anterograde flow rate (exercise: 438±32 mL/min vs. control: 364±46 mL/min;p=0.001) were larger for the exercise training group compared to controls, post-intervention. Although endothelial function was not different between groups, we observed an increase in microcirculatory dilatory capacity, as suggested by the augmented reactive hyperemia in the exercise training group. Novelty: • Endothelial function was not altered with exercise training during pregnancy. • Exercise training did contribute to improved cardiovascular outcomes, which may have been associated with augmented reactive hyperaemia, indicative of increased microcirculatory dilatory capacity.
Collapse
Affiliation(s)
- Rakhbeer Singh Boparai
- University of Alberta, Faculty of Kinesiology, Sport, and Recreation, Edmonton, Alberta, Canada;
| | - Rachel J Skow
- University of Alberta, Faculty of Physical Education and Recreation, 8602 112St NW, 1-052 Li Ka Shing Center, Edmonton, Alberta, Canada, T6G 2E3;
| | - Sauleha Farooq
- University of Alberta, Faculty of Kinesiology, Sport, and Recreation, Edmonton, Alberta, Canada;
| | - Craig D Steinback
- University of Alberta, Faculty of Physical Education and Recreation, -1059A Li Ka Shing Centre for Health Research Innovation, 8602-112 St., Edmonton, Alberta, Canada, T6G2E1;
| | - Margie H Davenport
- University of Alberta, Faculty of Kinesiology, Sport, and Recreation, Program for Pregnancy and Postpartum Health, 1-059A Li Ka Shing Center for Health Research Innovation, Edmonton, Alberta, Canada, T6G 2E1;
| |
Collapse
|
17
|
Abstract
In the 1950s, Arthur C. Guyton removed the heart from its pedestal in cardiovascular physiology by arguing that cardiac output is primarily regulated by the peripheral vasculature. This is counterintuitive, as modulating heart rate would appear to be the most obvious means of regulating cardiac output. In this Review, we visit recent and classic advances in comparative physiology in light of this concept. Although most vertebrates increase heart rate when oxygen demands rise (e.g. during activity or warming), experimental evidence suggests that this tachycardia is neither necessary nor sufficient to drive a change in cardiac output (i.e. systemic blood flow, Q̇ sys) under most circumstances. Instead, Q̇ sys is determined by the interplay between vascular conductance (resistance) and capacitance (which is mainly determined by the venous circulation), with a limited and variable contribution from heart function (myocardial inotropy). This pattern prevails across vertebrates; however, we also highlight the unique adaptations that have evolved in certain vertebrate groups to regulate venous return during diving bradycardia (i.e. inferior caval sphincters in diving mammals and atrial smooth muscle in turtles). Going forward, future investigation of cardiovascular responses to altered metabolic rate should pay equal consideration to the factors influencing venous return and cardiac filling as to the factors dictating cardiac function and heart rate.
Collapse
Affiliation(s)
- William Joyce
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark .,Department of Biology, University of Ottawa, 30 Marie Curie, Ottawa, ON K1N 6N5, Canada
| | - Tobias Wang
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark
| |
Collapse
|
18
|
Stuckless TJR, Vermeulen TD, Brown CV, Boulet LM, Shafer BM, Wakeham DJ, Steinback CD, Ayas NT, Floras JS, Foster GE. Acute intermittent hypercapnic hypoxia and sympathetic neurovascular transduction in men. J Physiol 2020; 598:473-487. [PMID: 31805605 DOI: 10.1113/jp278941] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/03/2019] [Indexed: 01/02/2023] Open
Abstract
KEY POINTS Intermittent hypoxia leads to long-lasting increases in muscle sympathetic nerve activity and blood pressure, contributing to increased risk for hypertension in obstructive sleep apnoea patients. We determined whether augmented vascular responses to increasing sympathetic vasomotor outflow, termed sympathetic neurovascular transduction (sNVT), accompanied changes in blood pressure following acute intermittent hypercapnic hypoxia in men. Lower body negative pressure was utilized to induce a range of sympathetic vasoconstrictor firing while measuring beat-by-beat blood pressure and forearm vascular conductance. IH reduced vascular shear stress and steepened the relationship between diastolic blood pressure and sympathetic discharge frequency, suggesting greater systemic sNVT. Our results indicate that recurring cycles of acute intermittent hypercapnic hypoxia characteristic of obstructive sleep apnoea could promote hypertension by increasing sNVT. ABSTRACT Acute intermittent hypercapnic hypoxia (IH) induces long-lasting elevations in sympathetic vasomotor outflow and blood pressure in healthy humans. It is unknown whether IH alters sympathetic neurovascular transduction (sNVT), measured as the relationship between sympathetic vasomotor outflow and either forearm vascular conductance (FVC; regional sNVT) or diastolic blood pressure (systemic sNVT). We tested the hypothesis that IH augments sNVT by exposing healthy males to 40 consecutive 1 min breathing cycles, each comprising 40 s of hypercapnic hypoxia ( P ETC O 2 : +4 ± 3 mmHg above baseline; P ET O 2 : 48 ± 3 mmHg) and 20 s of normoxia (n = 9), or a 40 min air-breathing control (n = 7). Before and after the intervention, lower body negative pressure (LBNP; 3 min at -15, -30 and -45 mmHg) was applied to elicit reflex increases in muscle sympathetic nerve activity (MSNA, fibular microneurography) when clamping end-tidal gases at baseline levels. Ventilation, arterial pressure [systolic blood pressure, diastolic blood pressure, mean arterial pressure (MAP)], brachial artery blood flow ( Q ̇ BA ), FVC ( Q ̇ BA /MAP) and MSNA burst frequency were measured continuously. Following IH, but not control, ventilation [5 L min-1 ; 95% confidence interval (CI) = 1-9] and MAP (5 mmHg; 95% CI = 1-9) were increased, whereas FVC (-0.2 mL min-1 mmHg-1 ; 95% CI = -0.0 to -0.4) and mean shear rate (-21.9 s-1 ; 95% CI = -5.8 to -38.0; all P < 0.05) were reduced. Systemic sNVT was increased following IH (0.25 mmHg burst-1 min-1 ; 95% CI = 0.01-0.49; P < 0.05), whereas changes in regional forearm sNVT were similar between IH and sham. Reductions in vessel wall shear stress and, consequently, nitric oxide production may contribute to heightened systemic sNVT and provide a potential neurovascular mechanism for elevated blood pressure in obstructive sleep apnoea.
Collapse
Affiliation(s)
- Troy J R Stuckless
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada
| | - Tyler D Vermeulen
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada
| | - Courtney V Brown
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada
| | - Lindsey M Boulet
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada
| | - Brooke M Shafer
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada
| | - Denis J Wakeham
- Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK
| | - Craig D Steinback
- Faculty of Kinesiology, Sport, and Recreation, University of Alberta, Edmonton, AB, Canada
| | - Najib T Ayas
- Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - John S Floras
- University Health Network and Mount Sinai Hospital Division of Cardiology, Toronto, ON, Canada.,Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Glen E Foster
- Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, Canada
| |
Collapse
|
19
|
Chaseling GK, Crandall CG, Gagnon D. Skin blood flow measurements during heat stress: technical and analytical considerations. Am J Physiol Regul Integr Comp Physiol 2019; 318:R57-R69. [PMID: 31596109 DOI: 10.1152/ajpregu.00177.2019] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
During heat stress, the skin vasculature can greatly increase conductance secondary to vasodilation. The subsequent increase in skin blood flow allows for convective heat transfer from the core to the skin and between the skin surface and the surrounding environment. Measurement of skin blood flow, therefore, provides valuable information regarding heat exchange between the body and the environment. In addition, assessment of skin blood flow can be used to study vascular control mechanisms. Most often, skin blood flow is measured by venous occlusion plethysmography, Doppler ultrasound, laser-Doppler flowmetry, and, more recently, optical coherence tomography. However, important delimitations to each of these methods, which may be dependent on the research question, must be considered when responses from these approaches are interpreted. In this brief review, we discuss these methods of skin blood flow measurement and highlight potential sources of error and limitations. We also provide recommendations to guide the interpretation of skin blood flow data.
Collapse
Affiliation(s)
- Georgia K Chaseling
- Cardiovascular Prevention and Rehabilitation Centre, Montreal Heart Institute, Montréal, Québec, Canada.,Département de Pharmacologie et Physiologie, Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| | - Craig G Crandall
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, and University of Texas Southwestern Medical Center, Dallas, Texas
| | - Daniel Gagnon
- Cardiovascular Prevention and Rehabilitation Centre, Montreal Heart Institute, Montréal, Québec, Canada.,Département de Pharmacologie et Physiologie, Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
| |
Collapse
|