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Romanchuk O. Cardiorespiratory dynamics during respiratory maneuver in athletes. FRONTIERS IN NETWORK PHYSIOLOGY 2023; 3. [DOI: https:/doi.org/10.3389/fnetp.2023.1276899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Introduction: The modern practice of sports medicine and medical rehabilitation requires the search for subtle criteria for the development of conditions and recovery of the body after diseases, which would have a prognostic value for the prevention of negative effects of training and rehabilitation tools, and also testify to the development and course of mechanisms for counteracting pathogenetic processes in the body. The purpose of this study was to determine the informative directions of the cardiorespiratory system parameters dynamics during the performing a maneuver with a change in breathing rate, which may indicate the body functional state violation.Methods: The results of the study of 183 healthy men aged 21.2 ± 2.3 years who regularly engaged in various sports were analyzed. The procedure for studying the cardiorespiratory system included conducting combined measurements of indicators of activity of the respiratory and cardiovascular systems in a sitting position using a spiroarteriocardiograph device. The duration of the study was 6 min and involved the sequential registration of three measurements with a change in breathing rate (spontaneous breathing, breathing at 0.1 Hz and 0.25 Hz).Results: Performing a breathing maneuver at breathing 0.1 Hz and breathing 0.25 Hz in comparison with spontaneous breathing leads to multidirectional significant changes in heart rate variability indicators–TP (ms2), LF (ms2), LFHF (ms2/ms2); of blood pressure variability indicators–TPDBP (mmHg2), LFSBP (mmHg2), LFDBP (mmHg2), HFSBP (mmHg2); of volume respiration variability indicators - LFR, (L×min-1)2; HFR, (L×min-1)2; LFHFR, (L×min-1)2/(L×min-1)2; of arterial baroreflex sensitivity indicators - BRLF (ms×mmHg-1), BRHF (ms×mmHg-1). Differences in indicators of systemic hemodynamics and indicators of cardiovascular and respiratory systems synchronization were also informative.Conclusion: According to the results of the study, it is shown that during performing a breathing maneuver with a change in the rate of breathing, there are significant changes in cardiorespiratory parameters, the analysis of which the increments made it possible to determine of the changes directions dynamics, their absolute values and informative limits regarding the possible occurrence of the cardiorespiratory interactions dysregulation.
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Romanchuk O. Cardiorespiratory dynamics during respiratory maneuver in athletes. FRONTIERS IN NETWORK PHYSIOLOGY 2023; 3:1276899. [PMID: 38020241 PMCID: PMC10643240 DOI: 10.3389/fnetp.2023.1276899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 10/19/2023] [Indexed: 12/01/2023]
Abstract
Introduction: The modern practice of sports medicine and medical rehabilitation requires the search for subtle criteria for the development of conditions and recovery of the body after diseases, which would have a prognostic value for the prevention of negative effects of training and rehabilitation tools, and also testify to the development and course of mechanisms for counteracting pathogenetic processes in the body. The purpose of this study was to determine the informative directions of the cardiorespiratory system parameters dynamics during the performing a maneuver with a change in breathing rate, which may indicate the body functional state violation. Methods: The results of the study of 183 healthy men aged 21.2 ± 2.3 years who regularly engaged in various sports were analyzed. The procedure for studying the cardiorespiratory system included conducting combined measurements of indicators of activity of the respiratory and cardiovascular systems in a sitting position using a spiroarteriocardiograph device. The duration of the study was 6 min and involved the sequential registration of three measurements with a change in breathing rate (spontaneous breathing, breathing at 0.1 Hz and 0.25 Hz). Results: Performing a breathing maneuver at breathing 0.1 Hz and breathing 0.25 Hz in comparison with spontaneous breathing leads to multidirectional significant changes in heart rate variability indicators-TP (ms2), LF (ms2), LFHF (ms2/ms2); of blood pressure variability indicators-TPDBP (mmHg2), LFSBP (mmHg2), LFDBP (mmHg2), HFSBP (mmHg2); of volume respiration variability indicators - LFR, (L×min-1)2; HFR, (L×min-1)2; LFHFR, (L×min-1)2/(L×min-1)2; of arterial baroreflex sensitivity indicators - BRLF (ms×mmHg-1), BRHF (ms×mmHg-1). Differences in indicators of systemic hemodynamics and indicators of cardiovascular and respiratory systems synchronization were also informative. Conclusion: According to the results of the study, it is shown that during performing a breathing maneuver with a change in the rate of breathing, there are significant changes in cardiorespiratory parameters, the analysis of which the increments made it possible to determine of the changes directions dynamics, their absolute values and informative limits regarding the possible occurrence of the cardiorespiratory interactions dysregulation.
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Affiliation(s)
- Oleksandr Romanchuk
- Department of Medical Rehabilitation, Ukrainian Research Institute of Medical Rehabilitation and Resort Therapy of the Ministry of Health of Ukraine, Odesa, Ukraine
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Lagatta DC, Fassini A, Terzian AL, Corrêa FMA, Resstel LBM. The medial prefrontal cortex and the cardiac baroreflex activity: physiological and pathological implications. Pflugers Arch 2023; 475:291-307. [PMID: 36695881 DOI: 10.1007/s00424-022-02786-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 12/16/2022] [Accepted: 12/25/2022] [Indexed: 01/26/2023]
Abstract
The cardiac baroreflex is an autonomic neural mechanism involved in the modulation of the cardiovascular system. It influences the heart rate and peripheral vascular resistance to preserve arterial blood pressure within a narrow variation range. This mechanism is mainly controlled by medullary nuclei located in the brain stem. However, supramedullary areas, such as the ventral portion of medial prefrontal cortex (vMPFC), are also involved. Particularly, the glutamatergic NMDA/NO pathway in the vMPFC can facilitate baroreflex bradycardic and tachycardic responses. In addition, cannabinoid receptors in this same area can reduce or increase those cardiac responses, possibly through alteration in glutamate release. This vMPFC network has been associated to cardiovascular responses during stressful situations. Recent results showed an involvement of glutamatergic, nitrergic, and endocannabinoid systems in the blood pressure and heart rate increases in animals after aversive conditioning. Consequently, baroreflex could be modified by the vMPFC neurotransmission during stressful situations, allowing necessary cardiovascular adjustments. Remarkably, some mental, neurological and neurodegenerative disorders can involve damage in the vMPFC, such as posttraumatic stress disorder, major depressive disorder, Alzheimer's disease, and neuropathic pain. These pathologies are also associated with alterations in glutamate/NO release and endocannabinoid functions along with baroreflex impairment. Thus, the vMPFC seems to play a crucial role on the baroreflex control, either during pathological or physiological stress-related responses. The study of baroreflex mechanism under such pathological view may be helpful to establish causality mechanisms for the autonomic and cardiovascular imbalance found in those conditions. It can explain in the future the reasons of the high cardiovascular risk some neurological and neurodegenerative disease patients undergo. Additionally, the present work offers insights on the possible contributions of vMPFC dysfunction on baroreflex alterations, which, in turn, may raise questions in what extent other brain areas may play a role in autonomic deregulation under such pathological situations.
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Affiliation(s)
- Davi C Lagatta
- Faculty of Pharmaceutical Sciences, Food and Nutrition, Federal University of Mato Grosso do Sul, MS, 79070-900, Campo Grande, Brazil
| | - Aline Fassini
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14090-900, Brazil
| | - Ana L Terzian
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14090-900, Brazil
| | - Fernando M A Corrêa
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14090-900, Brazil
| | - Leonardo B M Resstel
- Department of Pharmacology, Medical School of Ribeirão Preto, University of São Paulo, Avenida Bandeirantes 3900, Ribeirão Preto, SP, 14090-900, Brazil.
- Center for Interdisciplinary Research On Applied Neurosciences (NAPNA), Medical School of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, Brazil.
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Kullmann PHM, Horn JP. Patch-clamp analysis of nicotinic synapses whose strength straddles the firing threshold of rat sympathetic neurons. Front Neurosci 2022; 16:869753. [PMID: 36267230 PMCID: PMC9577239 DOI: 10.3389/fnins.2022.869753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 09/16/2022] [Indexed: 11/25/2022] Open
Abstract
Neurons in paravertebral sympathetic ganglia are innervated by converging nicotinic synapses of varying strength. Based upon intracellular recordings of excitatory postsynaptic potentials (EPSPs) with sharp microelectrodes these synapses were classified in the past as either primary (strong) or secondary (weak) by their ability to trigger postsynaptic action potentials. Here we present an analysis of 22 synapses whose strength straddled threshold, thereby distinguishing them from the original classification scheme for primary and secondary synapses. Recordings at 36°C were made from intact superior cervical ganglia isolated from 13 male and 3 female Sprague-Dawley rats and from 4 male spontaneously hypertensive (SHR) rats. Ganglia were pretreated with collagenase to permit patch recording. By dissecting a 1 cm length of the presynaptic cervical sympathetic nerve as part of the preparation and through use of graded presynaptic stimulation it was possible to fractionate synaptic inputs by their distinct latencies and magnitudes, and by the presynaptic stimulus threshold for each component. Comparison of cell-attached extracellular recordings with intracellular recordings of synaptic potentials and synaptic currents indicated that straddling EPSPs are not an artifact of shunting damage caused by intracellular recording. The results also showed that in cells where a single presynaptic shock elicits multiple action potentials, the response is driven by multiple synapses and not by repetitive postsynaptic firing. The conductance of straddling synapses also provides a direct estimate of the threshold synaptic conductance (9.8 nS ± 7.6 nS, n = 22, mean ± SD). The results are discussed in terms of their implications for ganglionic integration and an existing model of synaptic amplification.
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Prodel E, Gondim ML, Rocha HNM, Mira PAC, Nobrega ACL. Cardiovascular adjustments to cold pressor test in postmenopausal women and the impact of α1-adrenergic blockade. Clin Auton Res 2022; 32:261-269. [DOI: 10.1007/s10286-022-00879-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 07/09/2022] [Indexed: 11/03/2022]
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D'Souza AW, Klassen SA, Badrov MB, Lalande S, Shoemaker JK. Aging is associated with enhanced central, but impaired peripheral arms of the sympathetic baroreflex arc. J Appl Physiol (1985) 2022; 133:349-360. [PMID: 35736951 DOI: 10.1152/japplphysiol.00045.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We tested the hypothesis that the baroreflex control of action potential (AP) subpopulations would be blunted in older compared to young adults. Integrated muscle sympathetic nerve activity (MSNA) and the underlying sympathetic APs were obtained using microneurography and a continuous wavelet analysis approach, respectively, during 5 minutes of supine rest in 13 older (45-75 years, 6 females) and 14 young (21-30 years, 7 females) adults. Baroreflex threshold relationships were quantified as the slope of the linear regression between MSNA burst probability (%) and diastolic blood pressure (mmHg), or AP cluster firing probability (%) and diastolic blood pressure (mmHg). Integrated MSNA baroreflex threshold gain was greater in older compared to young adults (older: -7.6±3.6 %/mmHg vs. Young: -3.5±1.5 %/mmHg, P<0.001). Similarly, the baroreflex threshold gain of AP clusters was modified by aging (group-by-cluster effect: P<0.001) such that older adults demonstrated greater baroreflex threshold gains of medium-sized AP clusters (e.g., Cluster 4, older: -8.2±3.2 %/mmHg vs. Young: -3.6±1.9 %/mmHg, P=0.003) but not for the smallest- (Cluster 1, older: -1.6±1.9 %/mmHg vs. Young: -1.0±1.7 %/mmHg, P>0.999) and largest-sized (Cluster 10, older: -0.5±0.5 %/mmHg vs. Young: -0.2±0.1 %/mmHg, P=0.819) AP clusters compared to young adults. In contrast, the peak change in mean arterial pressure (MAP) following a spontaneous MSNA burst (i.e., sympathetic transduction) was impaired with aging (older: -0.7±0.3 mmHg vs. Young: 1.8±1.2 mmHg, P<0.001). We conclude that aging is associated with elevated baroreflex control over high-probability AP content of sympathetic bursts that may compensate for impaired sympathetic neurovascular transduction.
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Affiliation(s)
- Andrew W D'Souza
- Neurovascular research laboratory, School of Kinesiology, Western University, London, Ontario, Canada
| | - Stephen A Klassen
- Neurovascular research laboratory, School of Kinesiology, Western University, London, Ontario, Canada.,Department of Kinesiology, Brock University, St. Catharines, Ontario, Canada
| | - Mark B Badrov
- Neurovascular research laboratory, School of Kinesiology, Western University, London, Ontario, Canada.,University Health Network and Sinai Health System Division of Cardiology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Sophie Lalande
- Neurovascular research laboratory, School of Kinesiology, Western University, London, Ontario, Canada.,Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, 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
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Coovadia Y, Adler TE, Martin-Arrowsmith PW, Usselman CW. Sex differences in sympathetic neuro-vascular and neuro-hemodynamic relationships during the cold pressor test. Am J Physiol Regul Integr Comp Physiol 2022; 322:R411-R420. [PMID: 35293259 DOI: 10.1152/ajpregu.00223.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Muscle sympathetic nerve activity (MSNA) affects vascular resistance differently in women and men. However, whether this sex difference persists during pronounced increases in MSNA remains unclear. Therefore, the purpose of this study was to examine sex differences in neurovascular transduction during cold pressor test (CPT)-mediated sympatho-excitation. Integrated peroneal MSNA (microneurography) was measured at rest and during a 3-minute CPT in young healthy women (n=11) and men (n=10). Mean arterial pressure (MAP) was measured beat-by-beat (Finometer) and superficial femoral artery blood flow was measured using duplex ultrasound. Femoral vascular resistance (FVR) was quantified as MAP/femoral blood flow (mmHg/mL/min). Baseline MSNA was similar between women and men (14±9 vs 15±9 bursts/100hb, respectively; P=0.83), whereas MAP was lower (86±7 vs 92±4 mmHg; P=0.047), and FVR was greater in women than men (0.54±0.16 vs 0.36±0.15 mmHg/mL/min; P=0.02). CPT-induced increases in MSNA were similar between the sexes (+19±11 vs +26±14 bursts/100hb; P=0.26) while increases in MAP (+7±3 vs +10±3mmHg; P=0.03) and FVR (+3.2±18.6 vs +26.8±12.8%; P<0.01) were smaller in women than men. Within men, CPT- induced increases in MSNA predicted increases in MAP (R2=0.51, P=0.02) and FVR (R2=0.49, P=0.02). However, MSNA did not predict MAP (R2=0.11, P=0.35) or FVR (R2=0.07, P=0.46) in women. Our findings demonstrate that men experience robust CPT-induced MAP responses that are driven by both neuro-vascular (MSNA-FVR) and neuro-hemodynamic (MSNA-MAP) coupling. These relationships were not observed in women, indicating that even during pronounced increases in sympathetic outflow, MSNA is not predictive of vascular nor blood pressure outcomes in young healthy women.
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Affiliation(s)
- Yasmine Coovadia
- Cardiovascular Health and Autonomic Regulation Laboratory, McGill University, Montreal, Quebec, Canada
| | - Tessa E Adler
- Cardiovascular Health and Autonomic Regulation Laboratory, McGill University, Montreal, Quebec, Canada
| | - Patrick W Martin-Arrowsmith
- Exercise Metabolism and 6 Nutrition Research Lab, Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Charlotte W Usselman
- Cardiovascular Health and Autonomic Regulation Laboratory, McGill University, Montreal, Quebec, Canada.,McGill Research Centre for Physical Activity and Health, McGill University, Montreal, Quebec, Canada
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Modelling Female Physiology from Head to Toe: Impact of Sex Hormones, Menstrual Cycle, and Pregnancy. J Theor Biol 2022; 540:111074. [DOI: 10.1016/j.jtbi.2022.111074] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 12/14/2022]
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Trindade CO, Oliveira EC, Coelho DB, Casonatto J, Becker LK. Effects of Aquatic Exercise in Post-exercise Hypotension: A Systematic Review and Meta-Analysis. Front Physiol 2022; 13:834812. [PMID: 35173635 PMCID: PMC8841763 DOI: 10.3389/fphys.2022.834812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 01/06/2022] [Indexed: 11/13/2022] Open
Abstract
Background Post-exercise hypotension (PEH) can be an important non-pharmacological strategy in the treatment of arterial hypertension. Both aerobic and resistance exercises produce PEH, but it is not clear if the exercise environment can lead to a higher PEH. Objective This meta-analysis investigated whether a session of aquatic exercise (AE) induces PEH in comparison with control conditions such as land exercise (LE) or rest in hypertensive subjects. Methods The present systematic review and meta-analysis was conducted using the following electronic databases: PubMed, Google Scholar, and EMBASE. Ambulatory blood pressure measurements made in randomized clinical trials were pooled to compare PEH induced by AE with LE and rest conditions in hypertensive subjects. Results Data from four trials were included, which comprised 127 participants (94 women and 33 men). A 24-h analysis did not detect significant differences between AE and LE or rest for either systolic blood pressure (SBP) or diastolic blood pressure (DBP). Monitoring during the night showed that AE induced significant PEH in comparison with LE for SBP [−8.6 (−15.0 to −1.5) mmHg (p = 0.01)]. For DBP, the AE had pronounced PEH during the night in comparison with LE [−3.7 (−4.7 to −2.8) mmHg, p = 0.000] and rest [−1.7 (−1.9 to −0.8) mmHg, p = 0.000]. There were no differences in daytime values. Conclusion AE showed a higher PEH effect than LE sessions and rest conditions. PEH was observed in both SBP and DBP during the night. The number of studies was low, but all studies included in this meta-analysis used 24-h monitoring. The understanding of clinical relevance of AE, inducing a higher PEH, depends on a standardization of exercise protocols plus a rigorous monitoring of blood pressure. Systematic Review Registration PROSPERO registration: CRD42021271928.
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Affiliation(s)
- Cristina Oliveira Trindade
- Postgraduate Program in Health and Nutrition/PPGSN, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Emerson Cruz Oliveira
- Postgraduate Program in Health and Nutrition/PPGSN, Federal University of Ouro Preto, Ouro Preto, Brazil
- Physical Education Department, Physical Education School, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Daniel Barbosa Coelho
- Postgraduate Program in Health and Nutrition/PPGSN, Federal University of Ouro Preto, Ouro Preto, Brazil
- Physical Education Department, Physical Education School, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Juliano Casonatto
- Research Group in Physiology and Physical Activity, University of Northern Paraná, Londrina, Brazil
| | - Lenice Kappes Becker
- Postgraduate Program in Health and Nutrition/PPGSN, Federal University of Ouro Preto, Ouro Preto, Brazil
- Physical Education Department, Physical Education School, Federal University of Ouro Preto, Ouro Preto, Brazil
- *Correspondence: Lenice Kappes Becker
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Scalco A, Moro N, Mongillo M, Zaglia T. Neurohumoral Cardiac Regulation: Optogenetics Gets Into the Groove. Front Physiol 2021; 12:726895. [PMID: 34531763 PMCID: PMC8438220 DOI: 10.3389/fphys.2021.726895] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 07/27/2021] [Indexed: 12/25/2022] Open
Abstract
The cardiac autonomic nervous system (ANS) is the main modulator of heart function, adapting contraction force, and rate to the continuous variations of intrinsic and extrinsic environmental conditions. While the parasympathetic branch dominates during rest-and-digest sympathetic neuron (SN) activation ensures the rapid, efficient, and repeatable increase of heart performance, e.g., during the "fight-or-flight response." Although the key role of the nervous system in cardiac homeostasis was evident to the eyes of physiologists and cardiologists, the degree of cardiac innervation, and the complexity of its circuits has remained underestimated for too long. In addition, the mechanisms allowing elevated efficiency and precision of neurogenic control of heart function have somehow lingered in the dark. This can be ascribed to the absence of methods adequate to study complex cardiac electric circuits in the unceasingly moving heart. An increasing number of studies adds to the scenario the evidence of an intracardiac neuron system, which, together with the autonomic components, define a little brain inside the heart, in fervent dialogue with the central nervous system (CNS). The advent of optogenetics, allowing control the activity of excitable cells with cell specificity, spatial selectivity, and temporal resolution, has allowed to shed light on basic neuro-cardiology. This review describes how optogenetics, which has extensively been used to interrogate the circuits of the CNS, has been applied to untangle the knots of heart innervation, unveiling the cellular mechanisms of neurogenic control of heart function, in physiology and pathology, as well as those participating to brain-heart communication, back and forth. We discuss existing literature, providing a comprehensive view of the advancement in the understanding of the mechanisms of neurogenic heart control. In addition, we weigh the limits and potential of optogenetics in basic and applied research in neuro-cardiology.
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Affiliation(s)
- Arianna Scalco
- Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padova, Padova, Italy
- Veneto Institute of Molecular Medicine, Padova, Italy
| | - Nicola Moro
- Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padova, Padova, Italy
- Veneto Institute of Molecular Medicine, Padova, Italy
| | - Marco Mongillo
- Veneto Institute of Molecular Medicine, Padova, Italy
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Tania Zaglia
- Veneto Institute of Molecular Medicine, Padova, Italy
- Department of Biomedical Sciences, University of Padova, Padova, Italy
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Suarez-Roca H, Mamoun N, Sigurdson MI, Maixner W. Baroreceptor Modulation of the Cardiovascular System, Pain, Consciousness, and Cognition. Compr Physiol 2021; 11:1373-1423. [PMID: 33577130 DOI: 10.1002/cphy.c190038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Baroreceptors are mechanosensitive elements of the peripheral nervous system that maintain cardiovascular homeostasis by coordinating the responses to external and internal environmental stressors. While it is well known that carotid and cardiopulmonary baroreceptors modulate sympathetic vasomotor and parasympathetic cardiac neural autonomic drive, to avoid excessive fluctuations in vascular tone and maintain intravascular volume, there is increasing recognition that baroreceptors also modulate a wide range of non-cardiovascular physiological responses via projections from the nucleus of the solitary tract to regions of the central nervous system, including the spinal cord. These projections regulate pain perception, sleep, consciousness, and cognition. In this article, we summarize the physiology of baroreceptor pathways and responses to baroreceptor activation with an emphasis on the mechanisms influencing cardiovascular function, pain perception, consciousness, and cognition. Understanding baroreceptor-mediated effects on cardiac and extra-cardiac autonomic activities will further our understanding of the pathophysiology of multiple common clinical conditions, such as chronic pain, disorders of consciousness (e.g., abnormalities in sleep-wake), and cognitive impairment, which may result in the identification and implementation of novel treatment modalities. © 2021 American Physiological Society. Compr Physiol 11:1373-1423, 2021.
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Affiliation(s)
- Heberto Suarez-Roca
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University, Durham, North Carolina, USA
| | - Negmeldeen Mamoun
- Department of Anesthesiology, Division of Cardiothoracic Anesthesia and Critical Care Medicine, Duke University, Durham, North Carolina, USA
| | - Martin I Sigurdson
- Department of Anesthesiology and Critical Care Medicine, Landspitali, University Hospital, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - William Maixner
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University, Durham, North Carolina, USA
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Time-series analysis of heart rate and blood pressure in response to changes in work rate before and after 60 days of 6° head down tilt bed rest. Eur J Appl Physiol 2020; 121:1037-1048. [PMID: 33427969 PMCID: PMC7965855 DOI: 10.1007/s00421-020-04576-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 12/01/2020] [Indexed: 11/18/2022]
Abstract
Purpose Cardiovascular regulation during exercise, described using time series analysis, is expected to be attenuated after bed rest (BR) and this effect will be dampened by a reactive jumps countermeasure. Methods Twenty subjects (29 ± 6 years, 23.6 ± 1.7 kg m−2) were tested on a cycle ergometer 9 days (BDC-9) before the beginning of BR as well as 2 (R + 2) and 13 days (R + 13) after the end of BR, applying moderate pseudo-random binary (PRBS) work rate changes. Heart rate (HR) and mean arterial blood pressure (mBP) were measured beat-to-beat and interpolated to 1 s intervals. HR and mBP were cross-correlated [CCF(HR-mBP)] during the PRBS. Eleven subjects participated in a reactive jump countermeasure (JUMP) during the BR period, the other part of the group served as control group (CTRL). Results In the CTRL group, significantly lower CCF(HR-mBP) values during BDC-9 were observed compared to R + 2 during the lags 20–25 s and significantly higher values during the lags − 39 s to − 35 s. In the JUMP group, significantly lower CCFs were only observed at R + 2 compared with BDC-9 during the lags 23 s and 24 s, whereas the CCFs for BDC-9 were significantly higher at several lags compared with R + 13. Conclusion Attenuations in the regulation of the cardiovascular system during cycling exercise after BR were found in the CTRL group of the RSL study. Cardiovascular regulation in the JUMP group was improved compared to values before the beginning of BR, suggesting the effectiveness of the reactive jumps countermeasure to mitigate the deleterious effects of prolonged BR.
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Medeiros AR, Leicht AS, Michael S, Boullosa D. Weekly vagal modulations and their associations with physical fitness and physical activity. Eur J Sport Sci 2020; 21:1326-1336. [PMID: 33070741 DOI: 10.1080/17461391.2020.1838619] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The root mean square of successive differences (RMSSD) of R-R intervals, the most robust vagal modulation parameter of heart rate variability (HRV), has been proposed as a marker of global health and training adaptations. The weekly averaging of RMSSD and its natural logarithm (LnRMSSD) has been adopted to enhance detection of training-induced adaptations. We assessed measures of aerobic fitness, body composition, objective physical activity (PA), and daily LnRMSSD recordings during different conditions, such as supine rest, seated rest, standing and walking at 5 km/h, over a week in 34 healthy young individuals of both sexes (age: 22 ± 4 yr; body fatness: 20 ± 8%; estimated VO2max: 40 ± 8 mL·kg-1·min-1). The day-to-day reliability and agreement among LnRMSSD averages over 5, 4, 3, 2 and a single-day value per condition were assessed, while correlations between LnRMSSD, aerobic fitness, body composition, and PA were also examined. Poor to good day-to-day reliability, and moderate to excellent agreement were observed for LnRMSSD recordings for diverse conditions with a minimum of two daily recordings in the supine condition, and three in the other conditions achieving excellent agreement for weekly HRV assessment. Several correlations between LnRMSSD, aerobic fitness, body composition, and PA were revealed, with stronger observed associations during walking. Utilisation of weekly HRV (average of 2-3 daily recordings), as described in the current study, may provide practitioners with a tool to assess weekly vagal modulations for health and performance purposes. Walking HRV recordings may be a practical alternative to other conditions for the investigation of cardiac autonomic function.
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Affiliation(s)
| | - Anthony S Leicht
- Sport & Exercise Science, James Cook University, Townsville, Australia
| | - Scott Michael
- Centre for Human and Applied Physiology, University of Wollongong, Wollongong, Australia
| | - Daniel Boullosa
- Sport & Exercise Science, James Cook University, Townsville, Australia.,Graduate Program in Movement Sciences, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
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14
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Continuous cardiac autonomic and haemodynamic responses to isometric exercise in females. Eur J Appl Physiol 2020; 121:319-329. [PMID: 33070245 DOI: 10.1007/s00421-020-04525-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 10/06/2020] [Indexed: 12/13/2022]
Abstract
PURPOSE Hypertension is associated with impaired haemodynamic control mechanisms and autonomic dysfunction. Isometric exercise (IE) interventions have been shown to improve autonomic modulation and reduce blood pressure (BP) predominantly in male participants. The physiological responses to IE are unexplored in female populations; therefore, this study investigated the continous cardiac autonomic and haemodynamic response to a single bout of IE in a large female population. METHODS Forty physically inactive females performed a single, individually prescribed isometric wall squat training session. Total power spectral density of heart rate variability (HRV) and associated low-frequency (LF) and high-frequency (HF) power spectral components were recorded in absolute (ms2) and normalised units (nu) pre, during and post an IE session. Heart rate (HR) was recorded via electrocardiography and baroreceptor reflex sensitivity (BRS) via the sequence method. Continuous blood pressure was recorded via the vascular unloading technique and stroke volume via impedance cardiography. Total peripheral resistance (TPR) was calculated according to Ohm's law. RESULTS During IE, there were significant reductions in HRV (p < 0.001) and BRS (p < 0.001), and significant increases in heart rate (p < 0.001), systolic, mean and diastolic BP (p < 0.001 for all). In recovery following the IE session, cardiac autonomic parameters returned to baseline (p = 0.974); however, total peripheral vascular resistance significantly reduced below baseline (p < 0.001). This peripheral vascular response was associated with significant reductions in systolic (-17.3 ± 16.5 mmHg, p < 0.001), mean (-18.8 ± 17.4 mmHg, p < 0.001) and diastolic BP (-17.3 ± 16.2 mmHg, p < 0.001), below baseline. CONCLUSION A single IE session is associated with improved haemodynamic cardiovascular responses in females. Cardiac autonomic responses return to baseline values, which suggests that alternative mechanisms are responsible for the post-exercise haemodynamic improvements in females. Future mechanistic research is required to investigate the acute and chronic effects of IE in female populations with different resting BP profiles.
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15
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Christian LM, Koenig J, Williams DP, Kapuku G, Thayer JF. Impaired vasodilation in pregnant African Americans: Preliminary evidence of potential antecedents and consequences. Psychophysiology 2020; 58:e13699. [PMID: 33040402 DOI: 10.1111/psyp.13699] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 08/10/2020] [Accepted: 08/10/2020] [Indexed: 01/15/2023]
Abstract
Significant health disparities exist between African Americans (AA) and European Americans (EA) in hypertension and hypertension-related disorders. Evidence suggests that this is due to impaired vasodilation in AAs. Pregnancy is a potent systemic vasodilatory state. However, differences in vasodilation between AAs and EAs have not been investigated in pregnancy. We sought to examine the effects of pregnancy on vasodilation in AA and EA women and how this might be related to discrimination and low birth weight in their offspring. Hemodynamics [blood pressure (MAP), cardiac output (CO), total peripheral resistance (TPR)] and heart rate variability (HF-HRV) were examined at baseline in 40 pregnant AAs (n = 20) and EAs (n = 20) and matched nonpregnant women (n = 40). The Experiences of Discrimination scale and birth weight were also measured in the offspring of the pregnant participants. Whereas pregnancy was associated with decreased MAP independent of race, AAs showed impaired vasodilation independent of pregnancy status as indicated by greater TPR despite greater HF-HRV. In AAs, but not EAs, reports of fewer incidences of discrimination were associated with greater TPR. Finally, the HF-HRV of EA mothers was inversely related to the birth weight of their offspring but was uncorrelated in AAs. We report novel evidence of impaired vasodilation to an endogenous vasodilatory stimulus in AAs. Higher TPR was related to discrimination in AAs and higher HF-HRV was related to low birth weight in EAs. These findings have implications for understanding the intergenerational transmission of impaired vasodilation in AAs.
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Affiliation(s)
- Lisa M Christian
- Department of Psychiatry & Behavioral Health, The Ohio State University Wexner Medical Center, Columbus, OH, USA.,The Institute for Behavioral Medicine Research, The Ohio State University Wexner Medical Center, Columbus, OH, USA.,Department of Obstetrics and Gynecology, The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Julian Koenig
- Section for Experimental Child and Adolescent Psychiatry, Department of Child and Adolescent Psychiatry, Centre for Psychosocial Medicine, University of Heidelberg, Heidelberg, Germany.,University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - DeWayne P Williams
- Department of Psychological Science, The University of California Irvine, Irvine, CA, USA
| | - Gaston Kapuku
- Georgia Prevention Institute, Georgia Health Sciences University, Augusta, GA, USA
| | - Julian F Thayer
- Department of Psychological Science, The University of California Irvine, Irvine, CA, USA
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16
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Impaired cerebral blood flow regulation in chronic traumatic brain injury. Brain Res 2020; 1743:146924. [DOI: 10.1016/j.brainres.2020.146924] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/28/2020] [Accepted: 06/01/2020] [Indexed: 01/26/2023]
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17
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Trevisan IB, Vanderlei LCM, David RM, Santos CP, Ramos EMC, Ramos D. Influência de uma sessão de exercício aeróbico submáximo e máximo sobre o transporte mucociliar e função autonômica em tabagistas. FISIOTERAPIA E PESQUISA 2020. [DOI: 10.1590/1809-2950/20003627032020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
RESUMO O objetivo do estudo foi avaliar e correlacionar o comportamento da depuração mucociliar e do sistema nervoso autônomo de fumantes após sessões de exercício aeróbico submáximo e máximo. Foram avaliados 25 fumantes e 15 não fumantes, entre 30 e 50 anos. Ambos os grupos foram submetidos ao teste do tempo de trânsito de sacarina (TTS) e variabilidade da frequência cardíaca (VFC) antes e após uma sessão de exercício submáximo (teste de caminhada de seis minutos) e máximo (teste de exercício cardiopulmonar). Teste t pareado ou Wilcoxon foi utilizado para análise intragrupos e o teste t não pareado ou Mann-Whitney para a análise intergrupos. A correlação foi realizada utilizando os coeficientes de Pearson ou Spearman (p <0,05). Houve redução significativa do TTS após exercícios submáximo e máximo em ambos os grupos. Após o exercício submáximo, ambos grupos apresentaram redução significativa do intervalo RR e aumento da FC em comparação ao repouso, no grupo de não fumantes houve reduções significativas nos índices RMSSD, HFms² e SD1. Após o exercício máximo, ambos grupos apresentaram reduções significativas no SDNN, RMSSD, intervalo RR, LF e HF, em ms² e un, SD1 e SD2, além do aumento da FC, LFun e da razão LF/HF. Houve correlação positiva entre TTS e LFms² (r = 0,520, p = 0,008) após o exercício máximo para o grupo de fumantes. Conclui-se que independentemente da intensidade do exercício aeróbio, houve um aumento na depuração mucociliar em fumantes, mas essa alteração parece ser influenciada pelo sistema nervoso autônomo apenas frente o exercício máximo.
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Affiliation(s)
| | | | | | | | | | - Dionei Ramos
- Universidade Estadual Paulista Júlio de Mesquita Filho, Brasil
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18
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Young BE, Kaur J, Vranish JR, Stephens BY, Barbosa TC, Cloud JN, Wang J, Keller DM, Fadel PJ. Augmented resting beat-to-beat blood pressure variability in young, healthy, non-Hispanic black men. Exp Physiol 2020; 105:1102-1110. [PMID: 32362031 DOI: 10.1113/ep088535] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Accepted: 04/24/2020] [Indexed: 12/21/2022]
Abstract
NEW FINDINGS What is the central question of this study? The prevalence of hypertension in black individuals exceeds that in other racial groups. Despite this well-known heightened risk, the underlying contributory factors remain incompletely understood. We hypothesized that young black men would exhibit augmented beat-to-beat blood pressure variability compared with white men and that black men would exhibit augmented total peripheral resistance variability. What is the main finding and its importance? We demonstrate that young, healthy black men exhibit greater resting beat-to-beat blood pressure variability compared with their white counterparts, which is accompanied by greater variability in total peripheral resistance. These swings in blood pressure over time might contribute to the enhanced cardiovascular risk profile in black individuals. ABSTRACT The prevalence of hypertension in black (BL) individuals exceeds that in other racial groups. Recently, resting beat-to-beat blood pressure (BP) variability has been shown to predict cardiovascular risk and detect target organ damage better than ambulatory BP monitoring. Given the heightened risk in BL individuals, we hypothesized young BL men would exhibit augmented beat-to-beat BP variability compared with white (WH) men. Furthermore, given studies reporting reduced vasodilatation and augmented vasoconstriction in BL individuals, we hypothesized that BL men would exhibit augmented variability in total peripheral resistance (TPR). In 45 normotensive men (24 BL), beat-to-beat BP (Finometer) was measured during 10-20 min of quiet rest. Cardiac output and TPR were estimated (Modelflow method). Despite similar resting BP, BL men exhibited greater BP standard deviation (e.g. systolic BP SD; BL, 7.1 ± 2.2 mmHg; WH, 5.4 ± 1.5 mmHg; P = 0.006) compared with WH men, which was accompanied by a greater TPR SD (P = 0.003), but not cardiac output SD (P = 0.390). Other traditional measures of variability provided similar results. Histogram analysis indicated that BL men exhibited a greater percentage of cardiac cycles with BPs higher (> +10 mmHg higher) and lower (< -8 mmHg lower) than mean systolic BP compared with WH men (interaction, P < 0.001), which was accompanied by a greater percentage of cardiac cycles with high/low TPR (P < 0.001). In a subset of subjects (n = 30), reduced sympathetic baroreflex sensitivity was associated with augmented BP variability (r = -0.638, P < 0.001), whereas cardiac baroreflex sensitivity had no relationship (P = 0.447). Herein, we document an augmented beat-to-beat BP variability in young BL men, which coincided with fluctuations in vascular resistance and reduced sympathetic BRS.
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Affiliation(s)
- Benjamin E Young
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Jasdeep Kaur
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Jennifer R Vranish
- Department of Integrative Physiology and Health Science, Alma College, Alma, MI, USA
| | - Brandi Y Stephens
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Thales C Barbosa
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Jane N Cloud
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Jing Wang
- College of Nursing, University of Texas at Arlington, Arlington, TX, USA
| | - David M Keller
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
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19
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Duplicated Hering's nerves with formation of unusual neural loop. TRANSLATIONAL RESEARCH IN ANATOMY 2020. [DOI: 10.1016/j.tria.2019.100057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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20
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Teixeira AL, Fernandes IA, Vianna LC. GABA A receptors modulate sympathetic vasomotor outflow and the pressor response to skeletal muscle metaboreflex activation in humans. J Physiol 2019; 597:4139-4150. [PMID: 31247674 DOI: 10.1113/jp277929] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 06/24/2019] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS The activation of the group III/IV skeletal muscle afferents is one of the principal mediators of cardiovascular responses to exercise; however, the neuronal circuitry mechanisms that are involved during the activation of group III/IV muscle afferents in humans remain unknown. Recently, we showed that GABAergic mechanisms are involved in the cardiac vagal withdrawal during the activation of mechanically sensitive (predominantly mediated by group III fibres) skeletal muscle afferents in humans. In the present study, we found that increases in muscle sympathetic nerve activity and mean blood pressure during isometric handgrip exercise and postexercise ischaemia were significantly greater after the oral administration of diazepam, a benzodiazepine that increases GABAA activity, but not after placebo administration in young healthy subjects. These findings indicate for the first time that GABAA receptors modulate sympathetic vasomotor outflow and the pressor responses to activation of metabolically sensitive (predominantly mediated by group IV fibres) skeletal muscle afferents in humans. ABSTRACT Animal studies have indicated that GABAA receptors are involved in the neuronal circuitry of the group III/IV skeletal muscle afferent activation-induced neurocardiovascular responses to exercise. In the present study, we aimed to determine whether GABAA receptors modulate the neurocardiovascular responses to activation of metabolically sensitive (predominantly mediated by group IV fibres) skeletal muscle afferents in humans. In a randomized, double-blinded, placebo-controlled and cross-over design, 17 healthy subjects (eight women) performed 2 min of ischaemic isometric handgrip exercise at 30% of the maximal voluntary contraction followed by 2 min of postexercise ischaemia (PEI). Muscle sympathetic nerve activity (MSNA), blood pressure (BP) and heart rate (HR) were continuously measured and trials were conducted before and 60 min after the oral administration of either placebo or diazepam (10 mg), a benzodiazepine that enhances GABAA activity. At rest, MSNA was reduced, whereas HR and BP did not change after diazepam administration. During ischaemic isometric handgrip, greater MSNA (pre: ∆13 ± 9 bursts min-1 vs. post: ∆29 ± 15 bursts min-1 , P < 0.001), HR (pre: ∆23 ± 11 beats min-1 vs. post: ∆31 ± 17 beats min-1 , P < 0.01) and mean BP (pre: ∆33 ± 12 mmHg vs. post: ∆37 ± 12 mmHg, P < 0.01) responses were observed after diazepam. During PEI, MSNA and mean BP remained elevated from baseline before diazepam (∆10 ± 8 bursts min-1 and ∆25 ± 14 mmHg, respectively) and these elevations were increased after diazepam (∆17 ± 12 bursts min-1 and ∆28 ± 13 mmHg, respectively) (P ≤ 0.05). Importantly, placebo pill had no effect on neural, cardiac and pressor responses. These findings demonstrate for the first time that GABAA receptors modulate MSNA and the pressor responses to skeletal muscle metaboreflex activation in humans.
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Affiliation(s)
- André L Teixeira
- NeuroV̇ASQ̇ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, DF, Brazil
| | - Igor A Fernandes
- NeuroV̇ASQ̇ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, DF, Brazil
| | - Lauro C Vianna
- NeuroV̇ASQ̇ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, DF, Brazil
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21
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Teixeira AL. Lifelong high-altitude hypoxia induces arterial baroreflex adaptations: new insights and future directions. J Physiol 2019; 597:3253-3254. [PMID: 31078133 DOI: 10.1113/jp278174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- André L Teixeira
- Neuro V̇ASQ̇ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, DF, Brazil
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22
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Teixeira AL, Samora M, Vianna LC. Muscle metaboreflex activation via postexercise ischemia as a tool for teaching cardiovascular physiology for undergraduate students. ADVANCES IN PHYSIOLOGY EDUCATION 2019; 43:34-41. [PMID: 30540204 DOI: 10.1152/advan.00174.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The cardiovascular responses to exercise are mediated by several interactive neural mechanisms, including central command, arterial baroreflex, and skeletal muscle mechano- and metaboreflex. In humans, muscle metaboreflex activation can be isolated via postexercise ischemia (PEI), which increases sympathetic nerve activity and partially maintains the exercise-induced increase in arterial blood pressure. Here, we describe a practical laboratory class using PEI as a simple and useful technique to teach cardiovascular physiology. In an undergraduate exercise physiology class ( n = 47), a traditional 4-h lecture was conducted discussing the neural control mechanisms of cardiovascular regulation during exercise. Thereafter, eight students (4 men and 4 women) were selected to participate as a volunteer of a practical laboratory class. Each participant performed 90 s of isometric handgrip exercise at 40% of maximal voluntary contraction, followed by 3 min of PEI. Arterial blood pressure and heart rate were measured by digital monitors at rest and during isometric handgrip, PEI, and recovery. In addition, blood samples were collected from the tip of the exercising finger for blood lactate analyses. After the laboratory class, a survey was given to determine the perceptions of the students. The findings demonstrate that this laboratory class has proved to be highly popular with students, who self-reported a significant improvement in their understanding of several aspects of cardiovascular regulation during exercise.
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Affiliation(s)
- André L Teixeira
- NeuroV̇ASQ̇, Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília , Brasília , Brazil
| | - Milena Samora
- NeuroV̇ASQ̇, Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília , Brasília , Brazil
| | - Lauro C Vianna
- NeuroV̇ASQ̇, Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília , Brasília , Brazil
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23
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Hypotensive Effect of Heated Water-Based Exercise Persists After 12-Week Cessation of Training in Patients With Resistant Hypertension. Can J Cardiol 2018; 34:1641-1647. [PMID: 30527153 DOI: 10.1016/j.cjca.2018.09.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 09/27/2018] [Accepted: 09/29/2018] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Heated water-based exercise (HEx) promotes a marked reduction of blood pressure (BP), but it is not entirely clear whether its effects on BP persist after cessation of HEx. METHODS We analyzed the effects of cessation of HEx on 24-hour ambulatory BP monitoring (ABPM) in patients with resistant hypertension (RH). Thirty-two patients (aged 53 ± 6 years) with RH (4 to 6 antihypertensive drugs) were randomly assigned to HEx (n = 16) or control (n = 16) groups. Antihypertensive therapy remained unchanged during the protocol. The HEx group participated in 36 sessions (60 minutes) in a heated pool (32oC [89.6°F]) for 12 weeks (training), followed by 12 weeks of cessation of training. The control group was evaluated during the same period and instructed to maintain their habitual activities. RESULTS HEx and control groups had similar BP levels at baseline. HEx training reduced the 24-hour systolic (-19.5 ± 4.6 vs 3.0 ± 0.7 mm Hg, P = 0.001) and diastolic BP (-11.1 ± 2.4 vs 2.06 ± 0.9 mm Hg, P = 0.001) at week 12, compared with the control group. After 12 weeks of training cessation (week 24), 24-hour BP remained significantly lower in the HEx group than in the control group (-9.6 ± 3.8 vs 6.3 ± 3.5 mm Hg, P = 0.01 and -7.5±2.2 vs 2.2 ± 1.0 mm Hg, P = 0.009, for systolic and diastolic BP, respectively), although these differences were attenuated. CONCLUSIONS BP remained lower after cessation of 12-week training among patients with RH who underwent HEx compared with the controls. The carryover effects of HEx on BP may help to overcome the challenging problem of exercise compliance in long-term follow-up.
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24
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Sabino-Carvalho JL, Teixeira AL, Samora M, Daher M, Vianna LC. Blunted cardiovascular responses to exercise in Parkinson’s disease patients: role of the muscle metaboreflex. J Neurophysiol 2018; 120:1516-1524. [DOI: 10.1152/jn.00308.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Patients with Parkinson’s disease (PD) exhibit attenuated cardiovascular responses to exercise. The underlying mechanisms that are potentially contributing to these impairments are not fully understood. Therefore, we sought to test the hypothesis that patients with PD exhibit blunted cardiovascular responses to isolated muscle metaboreflex activation following exercise. For this, mean blood pressure, cardiac output, and total peripheral resistance were measured using finger photoplethysmography and the Modelflow method in 11 patients with PD [66 ± 2 yr; Hoehn and Yahr score: 2 ± 1 a.u.; time since diagnosis: 7 ± 1 yr; means ± SD) and 9 age-matched controls (66 ± 3 yr). Measurements were obtained at rest, during isometric handgrip exercise performed at 40% maximal voluntary contraction, and during postexercise ischemia. Also, a cold pressor test was assessed to confirm that blunted cardiovascular responses were specific to exercise and not representative of generalized sympathetic responsiveness. Changes in mean blood pressure were attenuated in patients with PD during handgrip (PD: ∆25 ± 2 mmHg vs. controls: ∆31 ± 3 mmHg; P < 0.05), and these group differences remained during postexercise ischemia (∆17 ± 1 mmHg vs. ∆26 ± 1 mmHg, respectively; P < 0.01). Additionally, changes in total peripheral resistance were attenuated during exercise and postexercise ischemia, indicating blunted reflex vasoconstriction in patients with PD. Responses to cold pressor test did not differ between groups, suggesting no group differences in generalized sympathetic responsiveness. Our results support the concept that attenuated cardiovascular responses to exercise observed in patients with PD are, at least in part, explained by an altered skeletal muscle metaboreflex. NEW & NOTEWORTHY Patients with Parkinson’s disease (PD) presented blunted cardiovascular responses to exercise. We showed that cardiovascular response evoked by the metabolic component of the exercise pressor reflex is blunted in patients with PD. Furthermore, patients with PD presented similar pressor response during the cold pressor test compared with age-matched controls. Altogether, our results support the hypothesis that attenuated cardiovascular responses to exercise observed in patients with PD are mediate by an altered skeletal muscle metaboreflex.
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Affiliation(s)
- Jeann L. Sabino-Carvalho
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - André L. Teixeira
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Milena Samora
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Maurício Daher
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Lauro C. Vianna
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
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25
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Al-Khazraji BK, Shoemaker JK. The human cortical autonomic network and volitional exercise in health and disease. Appl Physiol Nutr Metab 2018; 43:1122-1130. [PMID: 30058352 DOI: 10.1139/apnm-2018-0305] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The autonomic nervous system elicits continuous beat-by-beat homeostatic adjustments to cardiovascular control. These modifications are mediated by sensory inputs (e.g., baroreceptors, metaboreceptors, pulmonary, thermoreceptors, and chemoreceptors afferents), integration at the brainstem control centres (i.e., medulla), and efferent autonomic neural outputs (e.g., spinal, preganglionic, and postganglionic pathways). However, extensive electrical stimulation and functional imaging research show that the brain's higher cortical regions (e.g., insular cortex, medial prefrontal cortex, anterior cingulate cortex) partake in homeostatic regulation of the cardiovascular system at rest and during exercise. We now appreciate that these cortical areas form a network, namely the "cortical autonomic network" (CAN), which operate as part of a larger central autonomic network comprising 2-way communication of cortical and subcortical areas to exert autonomic influence. Interestingly, differential patterns of CAN activity and ensuing cardiovascular control are present in disease states, thereby highlighting the importance of considering the role of CAN as an integral aspect of cardiovascular regulation in health and disease. This review discusses current knowledge on human cortical autonomic activation during volitional exercise, and the role of exercise training on this activation in both health and disease.
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Affiliation(s)
- Baraa K Al-Khazraji
- a School of Kinesiology, Faculty of Health Sciences, University of Western Ontario, London, Ontario, Canada.,b Bone and Joint Institute, University of Western Ontario, London, Ontario, Canada
| | - J Kevin Shoemaker
- a School of Kinesiology, Faculty of Health Sciences, University of Western Ontario, London, Ontario, Canada.,b Bone and Joint Institute, University of Western Ontario, London, Ontario, Canada.,c Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, London, Ontario, Canada
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26
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Fonseca GF, Farinatti PTV, Midgley AW, Ferreira A, de Paula T, Monteiro WD, Cunha FA. Continuous and Accumulated Bouts of Cycling Matched by Intensity and Energy Expenditure Elicit Similar Acute Blood Pressure Reductions in Prehypertensive Men. J Strength Cond Res 2018; 32:857-866. [PMID: 29120987 DOI: 10.1519/jsc.0000000000002317] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fonseca, GF, Farinatti, PTV, Midgley, AW, Ferreira, A, de Paula, T, Monteiro, WD, and Cunha, FA. Continuous and accumulated bouts of cycling matched by intensity and energy expenditure elicit similar acute blood pressure reductions in prehypertensive men. J Strength Cond Res 32(3): 857-866, 2018-This study investigated differences in postexercise hypotension (PEH) after continuous vs. accumulated isocaloric bouts of cycling. Ten prehypertensive men, aged 23-34 years, performed 2 bouts of cycling at 75% oxygen uptake reserve, with total energy expenditures of 400 kcal per bout. One exercise bout was performed continuously (CONTIN) and the other as 2 smaller bouts each expending 200 kcal (INTER1 and INTER2). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and cardiac autonomic control were monitored in a supine position for 10 minutes before and 60 minutes after each exercise bout, and during a control session. Compared with control, blood pressure was significantly reduced after CONTIN (SBP: [INCREMENT] - 3.4 mm Hg, p < 0.001; MAP: [INCREMENT] - 2.5 mm Hg, p = 0.001), INTER1 (SBP: [INCREMENT] - 2.2 mm Hg, p = 0.045), and INTER2 (SBP: [INCREMENT] - 4.4 mm Hg, p < 0.001; DBP: [INCREMENT] - 2.7 mm Hg, p = 0.045; MAP: [INCREMENT] - 3.3 mm Hg, p = 0.001). The PEH was similar in CONTIN and INTER2, whereas INTER2 elicited greater PEH than INTER1 (SBP and MAP: [INCREMENT] - 2.0 and [INCREMENT] - 1.8 mm Hg, respectively, p ≤ 0.05). Increases in sympathovagal balance from baseline were inversely related to changes in SBP and DBP after CONTIN and INTER2 (r = -0.64 to -0.71; p = 0.021-0.047). These findings indicate that similar amounts of PEH are observed when exercise is performed as a single 400-kcal exercise bout or 2 × 200-kcal bouts and that the exercise recovery pattern of cardiac autonomic activity may be important in eliciting PEH.
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Affiliation(s)
- Guilherme F Fonseca
- Post-Graduate Program in Rehabilitation Sciences, Augusto Motta University Center (UNISUAM), Rio de Janeiro, Brazil
| | - Paulo T V Farinatti
- Post-Graduate Program in Exercise Science and Sports, University of Rio de Janeiro State, Rio de Janeiro, Brazil.,Laboratory of Physical Activity and Health Promotion, University of Rio de Janeiro State, Rio de Janeiro, Brazil.,Post-Graduate Program in Physical Activity Sciences, Salgado de Oliveira University, Rio de Janeiro, Brazil
| | - Adrian W Midgley
- Department of Sport and Physical Activity, Edge Hill University, Ormskirk, Lancashire, England
| | - Arthur Ferreira
- Post-Graduate Program in Rehabilitation Sciences, Augusto Motta University Center (UNISUAM), Rio de Janeiro, Brazil
| | - Tainah de Paula
- Laboratory of Physical Activity and Health Promotion, University of Rio de Janeiro State, Rio de Janeiro, Brazil.,Post-Graduate Program in Medical Sciences, Faculty of Medical Sciences, University of Rio de Janeiro State, Rio de Janeiro, Brazil
| | - Walace D Monteiro
- Laboratory of Physical Activity and Health Promotion, University of Rio de Janeiro State, Rio de Janeiro, Brazil.,Post-Graduate Program in Physical Activity Sciences, Salgado de Oliveira University, Rio de Janeiro, Brazil
| | - Felipe A Cunha
- Post-Graduate Program in Rehabilitation Sciences, Augusto Motta University Center (UNISUAM), Rio de Janeiro, Brazil.,Post-Graduate Program in Exercise Science and Sports, University of Rio de Janeiro State, Rio de Janeiro, Brazil.,Laboratory of Physical Activity and Health Promotion, University of Rio de Janeiro State, Rio de Janeiro, Brazil
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Vianna LC, Fernandes IA, Barbosa TC, Teixeira AL, Nóbrega ACL. Capsaicin-based analgesic balm attenuates the skeletal muscle metaboreflex in healthy humans. J Appl Physiol (1985) 2018; 125:362-368. [PMID: 29698108 DOI: 10.1152/japplphysiol.00038.2018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The exercise pressor reflex (EPR) is comprised of group III and IV skeletal muscle afferents and is one of the principal mediators of the cardiovascular response to exercise. In animals, capsaicin-based analgesic balm (CAP) attenuates the pressor response to muscle contraction, indicating the transient receptor potential vanilloid 1 (TRPv1) receptor (localized on the group IV afferent neuron) as an important mediator of the EPR. However, whether these findings can be extrapolated to humans remains unknown. Here, we tested the hypothesis that CAP would attenuate blood pressure (BP) and muscle sympathetic nerve activity (MSNA) responses to isolated muscle metaboreflex activation in healthy men. MSNA (microneurography) and beat-to-beat heart hate (HR, by electrocardiography), and BP (finger photoplethysmography) were continuously measured in eight healthy males (23 ± 5 yr) at rest, during isometric handgrip exercise, and during postexercise ischemia (PEI). Trials were performed before and 30 and 60 min after the topical application of CAP (0.1%, CAPZASIN-HP) over the volar forearm of the subject's exercising arm. Isometric exercise evoked increases in mean BP (∆32 ± 4 mmHg) and MSNA (∆26 ± 5 bursts/min; ∆19 ± 5 bursts/100 heart beats). The increases in BP during handgrip were not affected by CAP, but the increase in MSNA was lower after 60 min of CAP application. During PEI, the increases in BP and MSNA were all significantly less than those before CAP (all P < 0.05). In conclusion, CAP attenuated BP and sympathetic responses evoked by PEI in humans. These data provide evidence that transient receptor potential vanilloid 1 receptors potentially contribute to the EPR in humans, via its metabolic component. NEW & NOTEWORTHY We found that topical application of capsaicin-based analgesic balm attenuates arterial blood pressure and muscle sympathetic nerve activity during isolated muscle metaboreflex activation following isometric handgrip exercise in healthy humans. These findings suggest that the transient receptor potential vanilloid 1 may contribute to the exercise pressor reflex in humans via its metabolic component.
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Affiliation(s)
- Lauro C Vianna
- NeuroVASQ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília , Brasilia, Federal District , Brazil
| | - Igor A Fernandes
- NeuroVASQ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília , Brasilia, Federal District , Brazil.,Department of Physiology and Pharmacology, Fluminense Federal University , Niterói, Rio de Janeiro , Brazil
| | - Thales C Barbosa
- Department of Kinesiology, University of Texas at Arlington , Arlington, Texas
| | - André L Teixeira
- NeuroVASQ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília , Brasilia, Federal District , Brazil
| | - Antonio C L Nóbrega
- Department of Physiology and Pharmacology, Fluminense Federal University , Niterói, Rio de Janeiro , Brazil
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TEIXEIRA ANDRÉL, RITTI-DIAS RAPHAEL, ANTONINO DIEGO, BOTTARO MARTIM, MILLAR PHILIPJ, VIANNA LAUROC. Sex Differences in Cardiac Baroreflex Sensitivity after Isometric Handgrip Exercise. Med Sci Sports Exerc 2018; 50:770-777. [DOI: 10.1249/mss.0000000000001487] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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29
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Eddie D, Bates ME, Vaschillo EG, Lehrer PM, Retkwa M, Miuccio M. Rest, Reactivity, and Recovery: A Psychophysiological Assessment of Borderline Personality Disorder. Front Psychiatry 2018; 9:505. [PMID: 30386267 PMCID: PMC6199964 DOI: 10.3389/fpsyt.2018.00505] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 09/25/2018] [Indexed: 12/19/2022] Open
Abstract
Difficulty regulating emotion is a cardinal feature of borderline personality disorder (BPD), yet little is known about the automatic psychophysiological processes involved in this phenotype. Inconsistent findings have emerged from studies that employed limited assessments (e.g., heart rate variability, skin conductance) of autonomic nervous system response to emotional contexts, and compared groups based on the presence or absence of BPD as a categorical diagnosis. This exploratory study assessed a comprehensive set of autonomic nervous system processes in 44 individuals (22 with BPD) at rest, in response to emotionally evocative stimuli, and during a subsequent recovery period. BPD was characterized with a dimensional measure of BPD symptom severity, as a well by categorical diagnosis. At baseline and across experimental tasks, higher heart rate was observed in those diagnosed with BPD compared to controls, and in those expressing greater BPD symptom severity. These effects, however, were fully mediated by differences in physical exercise. In contrast, during recovery from emotional activation, greater symptom severity predicted consistently higher levels of multiple sympathetic and parasympathetic processes compared to lower symptom severity. Overall, these findings suggest that the heart rate elevations sometimes observed in those diagnosed with BPD may be associated with individual and group differences in levels of physical exercise. Results further indicate that adaptive psychophysiological recovery responses following emotional challenge may be disrupted in proportion to BPD symptom severity, independently of exercise. Results highlight the utility of considering lifestyle factors and symptom severity in studies of emotional activation and regulation processes in BPD.
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Affiliation(s)
- David Eddie
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Marsha E Bates
- Rutgers University - New Brunswick, Piscataway, NJ, United States
| | | | - Paul M Lehrer
- Rutgers University - New Brunswick, Piscataway, NJ, United States.,Rutgers Robert Wood Johnson Medical School, Piscataway, NJ, United States
| | - Michelle Retkwa
- Rutgers University - New Brunswick, Piscataway, NJ, United States
| | - Michael Miuccio
- Rutgers University - New Brunswick, Piscataway, NJ, United States
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30
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Teixeira AL, Ramos PS, Samora M, Sabino-Carvalho JL, Ricardo DR, Colombari E, Vianna LC. GABAergic contribution to the muscle mechanoreflex-mediated heart rate responses at the onset of exercise in humans. Am J Physiol Heart Circ Physiol 2017; 314:H716-H723. [PMID: 29351468 DOI: 10.1152/ajpheart.00557.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies have indicated that central GABAergic mechanisms are involved in the heart rate (HR) responses at the onset of exercise. On the basis of previous research that showed similar increases in HR during passive and active cycling, we reasoned that the GABAergic mechanisms involved in the HR responses at the exercise onset are primarily mediated by muscle mechanoreceptor afferents. Therefore, in this study, we sought to determine whether central GABA mechanisms are involved in the muscle mechanoreflex-mediated HR responses at the onset of exercise in humans. Twenty-eight healthy subjects (14 men and 14 women) aged between 18 and 35 yr randomly performed three bouts of 5-s passive and active cycling under placebo and after oral administration of diazepam (10 mg), a benzodiazepine that produces an enhancement in GABAA activity. Beat-to-beat HR (electrocardiography) and arterial blood pressure (finger photopletysmography) were continuously measured. Electromyography of the vastus lateralis was obtained to confirm no electrical activity during passive trials. HR increased from rest under placebo and further increased after administration of diazepam in both passive (change: 12 ± 1 vs. 17 ± 1 beats/min, P < 0.01) and active (change: 14 ± 1 vs. 18 ± 1 beats/min, P < 0.01) cycling. Arterial blood pressure increased from rest similarly during all conditions ( P > 0.05). Importantly, no sex-related differences were found in any variables during experiments. These findings demonstrate, for the first time, that the GABAergic mechanisms significantly contribute to the muscle mechanoreflex-mediated HR responses at the onset of exercise in humans. NEW & NOTEWORTHY We found that passive and voluntary cycling evokes similar increases in heart rate and that these responses were enhanced after diazepam administration, a benzodiazepine that enhances GABAA activity. These findings suggest that the GABAergic system may contribute to the muscle mechanoreflex-mediated vagal withdrawal at the onset of exercise in humans.
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Affiliation(s)
- André L Teixeira
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Plinio S Ramos
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil.,Maternity Hospital Therezinha de Jesus, Faculty of Health and Medical Sciences (SUPREMA), Juiz de Fora, Minas Gerais, Brazil
| | - Milena Samora
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Jeann L Sabino-Carvalho
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Djalma R Ricardo
- Maternity Hospital Therezinha de Jesus, Faculty of Health and Medical Sciences (SUPREMA), Juiz de Fora, Minas Gerais, Brazil
| | - Eduardo Colombari
- Department of Physiology and Pathology, School of Dentistry of Araraquara, São Paulo State University, UNESP, Araraquara, São Paulo , Brazil
| | - Lauro C Vianna
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
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31
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Teixeira AL, Daher M, Souza MC, Ramos PS, Fisher JP, Vianna LC. Sympathetically mediated cardiac responses to isolated muscle metaboreflex activation following exercise are modulated by body position in humans. Am J Physiol Heart Circ Physiol 2017; 314:H593-H602. [PMID: 29351473 DOI: 10.1152/ajpheart.00576.2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Isolated muscle metaboreflex activation with posthandgrip exercise ischemia (PEI) increases sympathetic nerve activity and partially maintains the exercise-induced increase in blood pressure, but a smaller heart rate (HR) response occurs. The cardiopulmonary baroreceptors, mechanically sensitive receptors that respond to changes in central blood volume and pressure, are strongly associated with changes in body position and upon activation elicit reflex sympathoinhibition. Here, we tested the hypothesis that postural changes modulate the sympathetically mediated cardiac response to PEI in humans. Beat-to-beat HR (electrocardiography) and blood pressure (finger photoplethysmography) were continuously measured, and cardiac function was assessed by echocardiography in 13 healthy men (21 ± 3 yr). After a 15-min rest period, 90-s static handgrip at 40% maximum voluntary contraction was performed followed by 3 min of PEI. Four trials were randomly conducted during either seated or supine position with and without β1-adrenergic blockade (25 mg atenolol). During PEI under control conditions, HR remained elevated from baseline in the seated [change (Δ): 4 ± 1 beats/min] but not in the supine (change: -1 ± 1 beats/min) position. Similarly, stroke volume and cardiac output were increased from baseline in the seated (∆13.0 ± 2.4 ml and ∆1.1 ± 0.2 l/min, respectively) but not in the supine (∆2.5 ± 2.9 ml and ∆0.13 ± 0.20 l/min, respectively) position. During β1-adrenergic blockade, HR, stroke volume, and cardiac output remained unchanged in both conditions. We conclude that sympathetically mediated cardiac responses to PEI are influenced by changes in body position. These findings indicated that muscle metaboreflex and cardiopulmonary baroreflex have an interactive influence on the neural control of cardiovascular function in humans. NEW & NOTEWORTHY In the present study, we demonstrated that muscle metaboreflex activation increases heart rate, stroke volume, and cardiac output in the seated position but not in the supine position and not after β1-adrenergic blockade. These findings indicate that sympathetically mediated cardiac responses to isolated muscle metaboreflex activation after exercise are modulated by central blood volume mobilization.
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Affiliation(s)
- André L Teixeira
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Mauricio Daher
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil.,Institute of Cardiology of Federal District, Brasília, Distrito Federal, Brazil
| | - Mayara C Souza
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
| | - Plinio S Ramos
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil.,Maternity Hospital Therezinha de Jesus, Faculty of Medical and Health Sciences-SUPREMA, Juiz de Fora, Minas Gerais, Brazil
| | - James P Fisher
- School of Sport, Exercise and Rehabilitation Sciences, College of Life and Environmental Sciences, University of Birmingham , Birmingham , United Kingdom
| | - Lauro C Vianna
- NeuroVASQ-Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasília, Brasília, Distrito Federal, Brazil
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Goswami N, Blaber AP, Hinghofer-Szalkay H, Montani JP. Orthostatic Intolerance in Older Persons: Etiology and Countermeasures. Front Physiol 2017; 8:803. [PMID: 29163185 PMCID: PMC5677785 DOI: 10.3389/fphys.2017.00803] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 09/29/2017] [Indexed: 12/16/2022] Open
Abstract
Orthostatic challenge produced by upright posture may lead to syncope if the cardiovascular system is unable to maintain adequate brain perfusion. This review outlines orthostatic intolerance related to the aging process, long-term bedrest confinement, drugs, and disease. Aging-associated illness or injury due to falls often leads to hospitalization. Older patients spend up to 83% of hospital admission lying in bed and thus the consequences of bedrest confinement such as physiological deconditioning, functional decline, and orthostatic intolerance represent a central challenge in the care of the vulnerable older population. This review examines current scientific knowledge regarding orthostatic intolerance and how it comes about and provides a framework for understanding of (patho-) physiological concepts of cardiovascular (in-) stability in ambulatory and bedrest confined senior citizens as well as in individuals with disease conditions [e.g., orthostatic intolerance in patients with diabetes mellitus, multiple sclerosis, Parkinson's, spinal cord injury (SCI)] or those on multiple medications (polypharmacy). Understanding these aspects, along with cardio-postural interactions, is particularly important as blood pressure destabilization leading to orthostatic intolerance affects 3-4% of the general population, and in 4 out of 10 cases the exact cause remains elusive. Reviewed also are countermeasures to orthostatic intolerance such as exercise, water drinking, mental arithmetic, cognitive training, and respiration training in SCI patients. We speculate that optimally applied countermeasures such as mental challenge maintain sympathetic activity, and improve venous return, stroke volume, and consequently, blood pressure during upright standing. Finally, this paper emphasizes the importance of an active life style in old age and why early re-mobilization following bedrest confinement or bedrest is crucial in preventing orthostatic intolerance, falls and falls-related injuries in older persons.
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Affiliation(s)
- Nandu Goswami
- Gravitational Physiology and Medicine Research Unit, Institute of Physiology, Medical University of Graz, Graz, Austria
| | - Andrew P Blaber
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, BC, Canada
| | - Helmut Hinghofer-Szalkay
- Gravitational Physiology and Medicine Research Unit, Institute of Physiology, Medical University of Graz, Graz, Austria
| | - Jean-Pierre Montani
- Department of Medicine/Physiology, University of Fribourg, Fribourg, Switzerland
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33
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Xu D, Verma AK, Garg A, Bruner M, Fazel-Rezai R, Blaber AP, Tavakolian K. Significant role of the cardiopostural interaction in blood pressure regulation during standing. Am J Physiol Heart Circ Physiol 2017. [PMID: 28626082 DOI: 10.1152/ajpheart.00836.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cardiovascular and postural control systems have been studied independently despite the increasing evidence showing the importance of cardiopostural interaction in blood pressure regulation. In this study, we aimed to assess the role of the cardiopostural interaction in relation to cardiac baroreflex in blood pressure regulation under orthostatic stress before and after mild exercise. Physiological variables representing cardiovascular control (heart rate and systolic blood pressure), lower limb muscle activation (electromyography), and postural sway (center of pressure derived from force and moment data during sway) were measured from 17 healthy participants (25 ± 2 yr, 9 men and 8 women) during a sit-to-stand test before and after submaximal exercise. The cardiopostural control (characterized by baroreflex-mediated muscle-pump effect in response to blood pressure changes, i.e., muscle-pump baroreflex) was assessed using wavelet transform coherence and causality analyses in relation to the baroreflex control of heart rate. Significant cardiopostural blood pressure control was evident counting for almost half of the interaction time with blood pressure changes that observed in the cardiac baroreflex (36.6-72.5% preexercise and 34.7-53.9% postexercise). Thus, cardiopostural input to blood pressure regulation should be considered when investigating orthostatic intolerance. A reduction of both cardiac and muscle-pump baroreflexes in blood pressure regulation was observed postexercise and was likely due to the absence of excessive venous pooling and a less stressed system after mild exercise. With further studies using more effective protocols evoking venous pooling and muscle-pump activity, the cardiopostural interaction could improve our understanding of the autonomic control system and ultimately lead to a more accurate diagnosis of cardiopostural dysfunctions.NEW & NOTEWORTHY We examined the interaction between cardiovascular and postural control systems during standing before and after mild exercise. Significant cardiopostural input to blood pressure regulation was shown, suggesting the importance of cardiopostural integration when investigating orthostatic hypotension. In addition, we observed a reduction of baroreflex-mediated blood pressure regulation after exercise.
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Affiliation(s)
- Da Xu
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Ajay K Verma
- Department of Electrical Engineering, University of North Dakota, Grand Forks, North Dakota; and
| | - Amanmeet Garg
- Department of Engineering Science, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Michelle Bruner
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Reza Fazel-Rezai
- Department of Electrical Engineering, University of North Dakota, Grand Forks, North Dakota; and
| | - Andrew P Blaber
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada.,Department of Electrical Engineering, University of North Dakota, Grand Forks, North Dakota; and
| | - Kouhyar Tavakolian
- Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada; .,Department of Electrical Engineering, University of North Dakota, Grand Forks, North Dakota; and
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Rhim JK, Jeon JP, Park JJ, Choi HJ, Cho YD, Sheen SH, Jang KS. Prediction of Prolonged Hemodynamic Instability During Carotid Angioplasty and Stenting. Neurointervention 2016; 11:120-6. [PMID: 27621949 PMCID: PMC5018548 DOI: 10.5469/neuroint.2016.11.2.120] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 08/25/2016] [Indexed: 11/24/2022] Open
Abstract
Purpose The aim of this study was to assess the risk factors of prolonged hemodynamic instability (HDI) after carotid angioplasty and stenting (CAS). Herein, a simplified predictive scoring system for prolonged HDI is proposed. Materials and Methods Sixty-six patients who had CAS from 2011 to 2016 at a single institution were evaluated. Prolonged HDI was defined as systolic blood pressure >160 mm Hg or <90 mm Hg or heart rate <50 beats/min, lasting over 30 minutes despite medical treatments. For the study, clinical data and radiologic data, including plaque morphology and stenosis were analyzed. Results Prolonged HDI was observed in 21 patients (31.8%). Multivariable analysis revealed that calcification (OR, 6.726; p=0.006), eccentric stenosis (OR, 3.645; p=0.047) and extensive plaque distribution (OR, 7.169; p=0.006) were related to prolonged HDI. According to these results, a simplified scoring scale was proposed based on the summation of points: 2 points for calcified plaque, 2 points for extensive plaque distribution, and 1 point for eccentric stenosis. The percentages of prolonged HDI according to the total score were as follows: score 0, 8.7%; score 1, 20.0%; score 2, 38.5%; score 3, 72.7%; score 4, 66.7%; score 5, 100%. From the analysis, the total score in patients with prolonged HDI was significantly higher than those without prolonged HDI (p<0.001). Conclusion Prolonged HDI can be associated with calcification of plaque, eccentric stenosis and extensive plaque distribution, and a simplified scoring system enables prediction of prolonged HDI according to our cohort.
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Affiliation(s)
- Jong Kook Rhim
- Department of Neurosurgery, Jeju National University College of Medicine, Jeju, Korea
| | - Jin Pyeong Jeon
- Department of Neurosurgery, Hallym University College of Medicine, Chuncheon, Korea
| | - Jeong Jin Park
- Department of Neurology, Konkuk University College of Medicine, Seoul, Korea
| | - Hyuk Jai Choi
- Department of Neurosurgery, Hallym University College of Medicine, Chuncheon, Korea
| | - Young Dae Cho
- Department of Radiology, Seoul National University College of Medicine, Seoul, Korea
| | - Seung Hun Sheen
- Department of Neurosurgery, Bundang Jesaeng Hospital, Bundang, Korea
| | - Kyung-Sool Jang
- Department of Neurosurgery, Catholic University College of Medicine, Incheon, Korea
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35
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Shoemaker JK, Badrov MB, Al-Khazraji BK, Jackson DN. Neural Control of Vascular Function in Skeletal Muscle. Compr Physiol 2015; 6:303-29. [PMID: 26756634 DOI: 10.1002/cphy.c150004] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The sympathetic nervous system represents a fundamental homeostatic system that exerts considerable control over blood pressure and the distribution of blood flow. This process has been referred to as neurovascular control. Overall, the concept of neurovascular control includes the following elements: efferent postganglionic sympathetic nerve activity, neurotransmitter release, and the end organ response. Each of these elements reflects multiple levels of control that, in turn, affect complex patterns of change in vascular contractile state. Primarily, this review discusses several of these control layers that combine to produce the integrative physiology of reflex vascular control observed in skeletal muscle. Beginning with three reflexes that provide somewhat dissimilar vascular patterns of response despite similar changes in efferent sympathetic nerve activity, namely, the baroreflex, chemoreflex, and muscle metaboreflex, the article discusses the anatomical and physiological bases of postganglionic sympathetic discharge patterns and recruitment, neurotransmitter release and management, and details of regional variations of receptor density and responses within the microvascular bed. Challenges are addressed regarding the fundamentals of measurement and how conclusions from one response or vascular segment should not be used as an indication of neurovascular control as a generalized physiological dogma. Whereas the bulk of the article focuses on the vasoconstrictor function of sympathetic neurovascular integration, attention is also given to the issues of sympathetic vasodilation as well as the impact of chronic changes in sympathetic activation and innervation on vascular health. © 2016 American Physiological Society.
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Affiliation(s)
- J K Shoemaker
- School of Kinesiology, Western University, London, Ontario, Canada.,Department of Physiology and Pharmacology, Western University, London, Ontario, Canada
| | - M B Badrov
- School of Kinesiology, Western University, London, Ontario, Canada
| | - B K Al-Khazraji
- Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - D N Jackson
- Department of Medical Biophysics, Western University, London, Ontario, Canada
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Lima EM, Nascimento AM, Brasil GA, Kalil IC, Lenz D, Endringer DC, Andrade TU, Bissoli NS. Cardiopulmonary reflex, cardiac cytokines, and nandrolone decanoate: response to resistance training in rats. Can J Physiol Pharmacol 2015; 93:985-91. [DOI: 10.1139/cjpp-2015-0014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study evaluated the effects of nandrolone associated with resistance training (RT) on cardiac cytokines, angiotensin-converting enzyme activity (ACEA), and the sensitivity of the Bezold-Jarisch reflex (BJR). Male Wistar rats were divided into 3 groups: CONT (received vehicle, no training); EXERC (RT: after one week of water adaptation, rats were exercised by jumping into water twice a week for 4 weeks), and ND+EXERC (received nandrolone decanoate 10 mg/kg, twice/week, i.m, associated with RT). The BJR was analysed by measuring bradycardic and hypotensive responses elicited by serotonin administration. Myocyte hypertrophy and matrix collagen deposition were determined by morphometric analysis of H&E and picrosirius red-stained samples, respectively. TNF-α and ACEA were also studied. RT promoted physiological myocyte hyrpertrophy but did not cause changes in the other parameters. The association of ND with RT increased myocyte hypertrophy, deposition of matrix type I collagen, TNF-α and ACEA; decreased IL-10, and impairment in the BJR were observed in ND+EXERC compared with CONT and EXERC. ND is associated with alterations in cardiac structure and function as a result of the development of pathological cardiac hypertrophy (cardiac cytokine imbalance, elevation of ACEA) and cardiac injury, even when combined with resistance training.
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Affiliation(s)
| | - Andrews Marques Nascimento
- Department of Pharmacy, University of Vila Velha, Espírito Santo, Brazil
- Department of Physiological Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Vitória, Espírito Santo 29042-755, Brazil
| | - Girlandia Alexandre Brasil
- Department of Pharmacy, University of Vila Velha, Espírito Santo, Brazil
- Department of Physiological Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Vitória, Espírito Santo 29042-755, Brazil
| | | | - Dominik Lenz
- Department of Pharmacy, University of Vila Velha, Espírito Santo, Brazil
| | | | | | - Nazaré Souza Bissoli
- Department of Physiological Sciences, Health Sciences Center, Federal University of Espírito Santo, Av. Marechal Campos, 1468, Vitória, Espírito Santo 29042-755, Brazil
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Cunha FA, Midgley AW, Soares PP, Farinatti PT. Postexercise hypotension after maximal short-term incremental exercise depends on exercise modality. Appl Physiol Nutr Metab 2015; 40:605-14. [DOI: 10.1139/apnm-2014-0354] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study investigated postexercise hypotension (PEH) after maximal cardiopulmonary exercise testing (CPET) performed using different exercise modalities. Twenty healthy men (aged 23 ± 3 years) performed 3 maximal CPETs (cycling, walking, and running), separated by 72 h in a randomized, counter-balanced order. Systolic (SBP) and diastolic blood pressure (DBP), heart rate, cardiac output, systemic vascular resistance (SVR), autonomic function (spontaneous baroreflex sensitivity (BRS) and heart rate variability (HRV)), and energy expenditure (EE) were assessed during a 60-min nonexercise control session and for 60 min immediately after each CPET. Total exercise volume (EE during CPET plus 60 min recovery) was significantly higher in running versus cycling and walking CPETs (P ≤ 0.001). Compared with control, only SBP after running CPET was significantly reduced (Δ = −6 ± 8 mm Hg; P < 0.001). Heart rate and cardiac output were significantly increased (P < 0.001) and SVR significantly decreased (P < 0.001) postexercise. BRS and HRV decreased after all CPETs (P < 0.001), whereas sympatho-vagal balance (low- and high-frequency (LF:HF) ratio) increased significantly after all exercise conditions, especially after running CPET (P < 0.001). Changes in SVR, BRS, sympathetic activity (low-frequency component of HRV), and LF:HF ratio were negatively correlated to variations in SBP (range −0.69 to −0.91; P < 0.001) and DBP (range −0.58 to −0.93; P ≤ 0.002). These findings suggest that exercise mode or the total exercise volume are major determinants of PEH magnitude in healthy men. Because of the running CPET, the PEH was primarily related to a decrease in SVR and to an increase in sympatho-vagal balance, which might be a reflex response to peripheral vasodilatation after exercise.
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Affiliation(s)
- Felipe A. Cunha
- Medical Sciences Graduate Program, Faculty of Medical Sciences, University of Rio de Janeiro State, Rio de Janeiro, Brazil
- Physical Activity and Health Promotion Laboratory, University of Rio de Janeiro State, Rio de Janeiro, Brazil
| | - Adrian W. Midgley
- Department of Sport and Physical Activity, Edge Hill University, Ormskirk, Lancashire, England
| | - Pedro P. Soares
- Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil
| | - Paulo T.V. Farinatti
- Physical Activity and Health Promotion Laboratory, University of Rio de Janeiro State, Rio de Janeiro, Brazil
- Physical Activity Sciences Graduate Program, Salgado de Oliveira University, Niterói, Brazil
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Kamoi S, Pretty C, Chiew YS, Davidson S, Pironet A, Desaive T, Shaw GM, Chase JG. Relationship between Stroke Volume and Pulse Wave Velocity. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.ifacol.2015.10.153] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Holwerda SW, Restaino RM, Fadel PJ. Adrenergic and non-adrenergic control of active skeletal muscle blood flow: implications for blood pressure regulation during exercise. Auton Neurosci 2014; 188:24-31. [PMID: 25467222 DOI: 10.1016/j.autneu.2014.10.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 09/18/2014] [Accepted: 10/13/2014] [Indexed: 12/13/2022]
Abstract
Blood flow to active skeletal muscle increases markedly during dynamic exercise. However, despite the massive capacity of skeletal muscle vasculature to dilate, arterial blood pressure is well maintained. Sympathetic nerve activity is elevated with increased intensity of dynamic exercise, and is essential for redistribution of cardiac output to active skeletal muscle and maintenance of arterial blood pressure. In addition, aside from the sympathetic nervous system, evidence from human studies is now emerging that supports roles for non-adrenergic vasoconstrictor pathways that become active during exercise and contribute to vasoconstriction in active skeletal muscle. Neuropeptide Y and adenosine triphosphate are neurotransmitters that are co-released with norepinephrine from sympathetic nerve terminals capable of producing vasoconstriction. Likewise, plasma concentrations of arginine vasopressin, angiotensin II (Ang II) and endothelin-1 (ET-1) increase during dynamic exercise, particularly at higher intensities. Ang II and ET-1 have both been shown to be important vasoconstrictor pathways for restraint of blood flow in active skeletal muscle and the maintenance of arterial blood pressure during exercise. Indeed, although both adrenergic and non-adrenergic vasoconstriction can be attenuated in exercising muscle with greater intensity of exercise, with the higher volume of blood flow, the active skeletal muscle vasculature remains capable of contributing importantly to the maintenance of blood pressure. In this brief review we provide an update on skeletal muscle blood flow regulation during exercise with an emphasis on adrenergic and non-adrenergic vasoconstrictor pathways and their potential capacity to offset vasodilation and aid in the regulation of blood pressure.
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Affiliation(s)
- Seth W Holwerda
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Robert M Restaino
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Paul J Fadel
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States.
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Stanley J, Peake JM, Buchheit M. Cardiac parasympathetic reactivation following exercise: implications for training prescription. Sports Med 2014; 43:1259-77. [PMID: 23912805 DOI: 10.1007/s40279-013-0083-4] [Citation(s) in RCA: 240] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of exercise training is to initiate desirable physiological adaptations that ultimately enhance physical work capacity. Optimal training prescription requires an individualized approach, with an appropriate balance of training stimulus and recovery and optimal periodization. Recovery from exercise involves integrated physiological responses. The cardiovascular system plays a fundamental role in facilitating many of these responses, including thermoregulation and delivery/removal of nutrients and waste products. As a marker of cardiovascular recovery, cardiac parasympathetic reactivation following a training session is highly individualized. It appears to parallel the acute/intermediate recovery of the thermoregulatory and vascular systems, as described by the supercompensation theory. The physiological mechanisms underlying cardiac parasympathetic reactivation are not completely understood. However, changes in cardiac autonomic activity may provide a proxy measure of the changes in autonomic input into organs and (by default) the blood flow requirements to restore homeostasis. Metaboreflex stimulation (e.g. muscle and blood acidosis) is likely a key determinant of parasympathetic reactivation in the short term (0-90 min post-exercise), whereas baroreflex stimulation (e.g. exercise-induced changes in plasma volume) probably mediates parasympathetic reactivation in the intermediate term (1-48 h post-exercise). Cardiac parasympathetic reactivation does not appear to coincide with the recovery of all physiological systems (e.g. energy stores or the neuromuscular system). However, this may reflect the limited data currently available on parasympathetic reactivation following strength/resistance-based exercise of variable intensity. In this review, we quantitatively analyse post-exercise cardiac parasympathetic reactivation in athletes and healthy individuals following aerobic exercise, with respect to exercise intensity and duration, and fitness/training status. Our results demonstrate that the time required for complete cardiac autonomic recovery after a single aerobic-based training session is up to 24 h following low-intensity exercise, 24-48 h following threshold-intensity exercise and at least 48 h following high-intensity exercise. Based on limited data, exercise duration is unlikely to be the greatest determinant of cardiac parasympathetic reactivation. Cardiac autonomic recovery occurs more rapidly in individuals with greater aerobic fitness. Our data lend support to the concept that in conjunction with daily training logs, data on cardiac parasympathetic activity are useful for individualizing training programmes. In the final sections of this review, we provide recommendations for structuring training microcycles with reference to cardiac parasympathetic recovery kinetics. Ultimately, coaches should structure training programmes tailored to the unique recovery kinetics of each individual.
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Affiliation(s)
- Jamie Stanley
- Centre of Excellence for Applied Sport Science Research, Queensland Academy of Sport, Brisbane, QLD, Australia,
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Jung KT, Kim SH, Lee HY, Jung JD, Yu BS, Lim KJ, So KY, Lee JY, An TH. Effect on thermoregulatory responses in patients undergoing a tympanoplasty in accordance to the anesthetic techniques during PEEP: a comparison between inhalation anesthesia with desflurane and TIVA. Korean J Anesthesiol 2014; 67:32-7. [PMID: 25097736 PMCID: PMC4121491 DOI: 10.4097/kjae.2014.67.1.32] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/06/2014] [Accepted: 01/09/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It has been known that positive end-expiratory pressure (PEEP) increases the vasoconstriction threshold by baroreceptor unloading. We compared the effect on the thermoregulatory responses according to anesthetic techniques between an inhalation anesthesia with desflurane and a total intravenous anesthesia (TIVA) with propofol and reminfentanil when PEEP was applied in patients undergoing tympanoplasty. METHODS Forty-six patients with a scheduled tympanoplasty were enrolled and the patients were divided in two study groups. Desflurane was used as an inhalation anesthetic in group 1 (n = 22), while TIVA with propofol and remifentanil was used in group 2 (n = 24). PEEP was applied by 5 cmH2O in both groups and an ambient temperature was maintained at 22-24℃ during surgery. The core temperature and the difference of skin temperature between forearm and fingertip were monitored for about 180 minutes before and after the induction of general anesthesia. RESULTS The final core temperature was significantly higher in group 2 (35.4 ± 0.7℃) than in group 1 (34.9 ± 0.5℃). Peripheral thermoregulatory vasoconstriction was found in 5 subjects (23%) in group 1 and in 21 subjects (88%) in group 2. The time taken for reaching the thermoregulatory vasoconstriction threshold was 151.4 ± 19.7 minutes in group 1 and 88.9 ± 14.4 minutes in group 2. CONCLUSIONS When PEEP will be applied, anesthesia with TIVA may have more advantages in core temperature preservation than an inhalation anesthesia with desflurane.
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Affiliation(s)
- Ki Tae Jung
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Sang Hun Kim
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Hyun Young Lee
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Jong Dal Jung
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Byung Sik Yu
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Kyung Joon Lim
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Keum Young So
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
| | - Ju Young Lee
- Department of Anesthesiology and Pain Medicine, Chosun University Hospital, Gwangju, Korea
| | - Tae Hun An
- Department of Anesthesiology and Pain Medicine, Chosun University School of Medicine, Gwangju, Korea
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Credeur DP, Holwerda SW, Boyle LJ, Vianna LC, Jensen AK, Fadel PJ. Effect of aging on carotid baroreflex control of blood pressure and leg vascular conductance in women. Am J Physiol Heart Circ Physiol 2014; 306:H1417-25. [PMID: 24682393 DOI: 10.1152/ajpheart.00036.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recent work suggests that β-adrenergic vasodilation offsets α-adrenergic vasoconstriction in young women, but this effect is lost after menopause. Given these age-related vascular changes, we tested the hypothesis that older women would exhibit a greater change in vascular conductance following baroreflex perturbation compared with young women. In 10 young (21 ± 1 yr) and 10 older (62 ± 2 yr) women, mean arterial pressure (MAP; Finometer), heart rate (HR), cardiac output (CO; Modelflow), total vascular conductance (TVC), and leg vascular conductance (LVC, duplex-Doppler ultrasound) were continuously measured in response to 5-s pulses of neck suction (NS; -60 Torr) and neck pressure (NP; +40 Torr) to simulate carotid hypertension and hypotension, respectively. Following NS, decreases in MAP were similar between groups; however, MAP peak response latency was slower in older women (P < 0.05). Moreover, at the time of peak MAP, increases in LVC (young, -11.5 ± 3.9%LVC vs. older, +19.1 ± 7.0%LVC; P < 0.05) and TVC were greater in older women, whereas young women exhibited larger decreases in HR and CO (young, -10 ± 3% CO vs. older, +0.8 ± 2% CO; P < 0.05). Following NP, increases in MAP were blunted (young, +14 ± 1 mmHg vs. older, +8 ± 1 mmHg; P < 0.05) in older women, whereas MAP response latencies were similar. Interestingly, decreases in LVC and TVC were similar between groups, but HR and CO (young, +7.0 ± 2% CO vs. older, -4.0 ± 2% CO; P < 0.05) responses were attenuated in older women. These findings suggest that older women have greater reliance on vascular conductance to modulate MAP via carotid baroreflex, whereas young women rely more on cardiac responsiveness. Furthermore, older women demonstrate a blunted ability to increase MAP to hypotensive stimuli.
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Affiliation(s)
| | | | | | - Lauro C Vianna
- Department of Physiology and Pharmacology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil
| | | | - Paul J Fadel
- Departments of Medical Pharmacology and Physiology, and Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri;
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Pires W, Wanner SP, Lima MRM, Fonseca IAT, Fumega U, Haibara AS, Coimbra CC, Lima NRV. Physical exercise performance in temperate and warm environments is decreased by an impaired arterial baroreflex. PLoS One 2013; 8:e72005. [PMID: 23951278 PMCID: PMC3737155 DOI: 10.1371/journal.pone.0072005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 07/10/2013] [Indexed: 11/18/2022] Open
Abstract
The present study aimed to investigate whether running performance in different environments is dependent on intact arterial baroreceptor reflexes. We also assessed the exercise-induced cardiovascular and thermoregulatory responses in animals lacking arterial baroafferent signals. To accomplish these goals, male Wistar rats were subjected to sinoaortic denervation (SAD) or sham surgery (SHAM) and had a catheter implanted into the ascending aorta to record arterial pressure and a telemetry sensor implanted in the abdominal cavity to record core temperature. After recovering from these surgeries, the animals were subjected to constant- or incremental-speed exercises performed until the voluntary interruption of effort under temperate (25° C) and warm (35° C) conditions. During the constant-speed exercises, the running time until the rats were fatigued was shorter in SAD rats in both environments. Although the core temperature was not significantly different between the groups, tail skin temperature was higher in SAD rats under temperate conditions. The denervated rats also displayed exaggerated increases in blood pressure and double product compared with the SHAM rats; in particular, in the warm environment, these exaggerated cardiovascular responses in the SAD rats persisted until they were fatigued. These SAD-mediated changes occurred in parallel with increased variability in the very low and low components of the systolic arterial pressure power spectrum. The running performance was also affected by SAD during the incremental-speed exercises, with the maximal speed attained being decreased by approximately 20% in both environments. Furthermore, at the maximal power output tolerated during the incremental exercises, the mean arterial pressure, heart rate and double product were exaggerated in the SAD relative to SHAM rats. In conclusion, the chronic absence of the arterial baroafferents accelerates exercise fatigue in temperate and warm environments. Our findings also suggest that an augmented cardiovascular strain accounted for the early interruption of exercise in the SAD rats.
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Affiliation(s)
- Washington Pires
- Exercise Physiology Laboratory, Department of Physical Education, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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Greaney JL, Schwartz CE, Edwards DG, Fadel PJ, Farquhar WB. The neural interaction between the arterial baroreflex and muscle metaboreflex is preserved in older men. Exp Physiol 2013; 98:1422-31. [PMID: 23733520 DOI: 10.1113/expphysiol.2013.073189] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Sympathetic baroreflex sensitivity is increased during selective activation of the skeletal muscle metaboreflex with postexercise ischaemia (PEI) in young adults. However, to date, there are no data demonstrating this neural interaction between the arterial baroreflex and the muscle metaboreflex in healthy older adults. Therefore, the goal of the present study was to examine the influence of healthy ageing on the metabolic component of the exercise pressor reflex and its interaction with the arterial baroreflex in the control of sympathetic outflow. Postexercise ischaemia following static hand grip performed at 30% maximal voluntary contraction was used to isolate muscle metaboreflex activation in young [n = 10; 24 ± 1 years old; resting blood pressure (BP) 116 ± 3/64 ± 3 mmHg] and older men (n = 9; 59 ± 2 years old; resting BP 120 ± 2/77 ± 2 mmHg). Arterial BP (Finometer) and muscle sympathetic nerve activity (MSNA) were measured continuously. Weighted linear regression analysis between MSNA and diastolic BP was used to estimate arterial baroreflex MSNA gain. There were no age-related differences in the increase in mean BP (young, Δ14 ± 3 mmHg versus older, Δ15 ± 2 mmHg; P > 0.05) or MSNA burst frequency (young, Δ11 ± 2 bursts min(-1) versus older, Δ9 ± 1 bursts min(-1); P > 0.05) during PEI. Likewise, the gain of arterial baroreflex control of total MSNA increased to a similar extent in both groups during PEI (young, -4.2 ± 0.9 baseline versus -6.3 ± 1.1 PEI a.u. beat(-1) mmHg(-1); and older, -3.7 ± 1.1 baseline versus -6.7 ± 1.4 PEI a.u. beat(-1) mmHg(-1); P < 0.05 for both). Collectively, these findings indicate that the neural interaction between the arterial baroreflex and the skeletal muscle metaboreflex in the regulation of MSNA is preserved in healthy ageing.
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Affiliation(s)
- Jody L Greaney
- W. B. Farquhar: 541 South College Avenue, Fred Rust HPL - Office #143, Newark, DE 19716, USA.
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Fairfax ST, Holwerda SW, Credeur DP, Zuidema MY, Medley JH, Dyke PC, Wray DW, Davis MJ, Fadel PJ. The role of α-adrenergic receptors in mediating beat-by-beat sympathetic vascular transduction in the forearm of resting man. J Physiol 2013; 591:3637-49. [PMID: 23652594 DOI: 10.1113/jphysiol.2013.250894] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Sympathetic vascular transduction is commonly understood to act as a basic relay mechanism, but under basal conditions, competing dilatory signals may interact with and alter the ability of sympathetic activity to decrease vascular conductance. Thus, we determined the extent to which spontaneous bursts of muscle sympathetic nerve activity (MSNA) mediate decreases in forearm vascular conductance (FVC) and the contribution of local α-adrenergic receptor-mediated pathways to the observed FVC responses. In 19 young men, MSNA (microneurography), arterial blood pressure and brachial artery blood flow (duplex Doppler ultrasound) were continuously measured during supine rest. These measures were also recorded in seven men during intra-arterial infusions of normal saline, phentolamine (PHEN) and PHEN with angiotensin II (PHEN+ANG). The latter was used to control for increases in resting blood flow with α-adrenergic blockade. Spike-triggered averaging was used to characterize beat-by-beat changes in FVC for 15 cardiac cycles following each MSNA burst and a peak response was calculated. Following MSNA bursts, FVC initially increased by +3.3 ± 0.3% (P = 0.016) and then robustly decreased to a nadir of -5.8 ± 1.6% (P < 0.001). The magnitude of vasoconstriction appeared graded with the number of consecutive MSNA bursts; while individual burst size only had a mild influence. Neither PHEN nor PHEN+ANG infusions affected the initial rise in FVC, but both infusions significantly attenuated the subsequent decrease in FVC (-2.1 ± 0.7% and -0.7 ± 0.8%, respectively; P < 0.001 vs. normal saline). These findings indicate that spontaneous MSNA bursts evoke robust beat-by-beat decreases in FVC that are exclusively mediated via α-adrenergic receptors.
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Affiliation(s)
- Seth T Fairfax
- Biomedical Sciences, University of Missouri, Columbia, MO 65212, USA
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Jeon JS, Sheen SH, Hwang G. Hemodynamic instability during carotid angioplasty and stenting-relationship of calcified plaque and its characteristics. Yonsei Med J 2013; 54:295-300. [PMID: 23364959 PMCID: PMC3575967 DOI: 10.3349/ymj.2013.54.2.295] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE During carotid angioplasty and stenting (CAS), hemodynamic instability (HDI) can occur, possibly causing post-procedural ischemic complications. The goal of this study was to investigate the risk factors of HDI focusing on characteristics of plaque. MATERIALS AND METHODS Thirty nine CAS patients were retrospectively evaluated for HDI. Prolonged HDI that lasted over 30 minutes was analyzed in relation to characteristics of calcified plaque. RESULTS Nineteen (48.7%) patients had HDI. Ten of the 19 had both bradycardia and hypotension, and nine had only bradycardia. All bradycardia was treated well with a transcutaneous temporary cardiac pacemaker. But eight patients presented with prolonged hypotension in spite of recovery of bradycardia. Calcified plaque was a related factor associated with HDI (odds ratio, 8.571; 95% confidence interval, 1.321-55.62; p=0.024). Extensive and eccentric type calcified plaques were associated with prolonged hypotension (p=0.04, and p=0.028, respectively). CONCLUSION The calcification of plaque is a predictable factor of HDI during CAS, and its extensive and eccentric calcified plaques may be related to prolonged HDI.
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Affiliation(s)
- Jin Sue Jeon
- Department of Neurosurgery, Hallym University College of Medicine, Chuncheon Sacred Heart Hospital, Chuncheon, Korea
| | - Seung Hun Sheen
- Department of Neurosurgery, Hallym University College of Medicine, Chuncheon Sacred Heart Hospital, Chuncheon, Korea
| | - Gyojun Hwang
- Department of Neurosurgery, Hallym University College of Medicine, Chuncheon Sacred Heart Hospital, Chuncheon, Korea
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Vianna LC, Hart EC, Fairfax ST, Charkoudian N, Joyner MJ, Fadel PJ. Influence of age and sex on the pressor response following a spontaneous burst of muscle sympathetic nerve activity. Am J Physiol Heart Circ Physiol 2012; 302:H2419-27. [PMID: 22427525 DOI: 10.1152/ajpheart.01105.2011] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The sympathetic nervous system is critical for the beat-to-beat regulation of arterial blood pressure (BP). Although studies have examined age- and sex-related effects on BP control, findings are inconsistent and limited data are available in postmenopausal women. In addition, the majority of studies have focused on time-averaged responses without consideration for potential beat-to-beat alterations. Thus we examined whether the ability of muscle sympathetic nerve activity (MSNA) to modulate BP on a beat-to-beat basis is affected by age or sex. BP and MSNA were measured during supine rest in 40 young (20 men) and 40 older (20 men) healthy subjects. Beat-to-beat fluctuations in mean arterial pressure (MAP) were characterized for 15 cardiac cycles after each MSNA burst using signal averaging. The rise in MAP following an MSNA burst was similar between young men and women (+2.64 ± 0.3 vs. +2.57 ± 0.3 mmHg, respectively). However, the magnitude of the increase in MAP after an MSNA burst was reduced in older compared with young subjects (P < 0.05). Moreover, the attenuation of the pressor response was greater in older women (+1.20 ± 0.1 mmHg) compared with older men (+1.72 ± 0.2 mmHg; P < 0.05). Interestingly, in all groups, MAP consistently decreased after cardiac cycles without MSNA bursts (nonbursts) with the magnitude of fall greatest in older men. In summary, healthy aging is associated with an attenuated beat-to-beat increase in BP after a spontaneous MSNA burst, and this attenuation is more pronounced in postmenopausal women. Furthermore, our nonburst findings highlight the importance of sympathetic vasoconstrictor activity to maintain beat-to-beat BP, particularly in older men.
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Affiliation(s)
- Lauro C Vianna
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, 65212, USA
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Kim A, Deo SH, Fisher JP, Fadel PJ. Effect of sex and ovarian hormones on carotid baroreflex resetting and function during dynamic exercise in humans. J Appl Physiol (1985) 2012; 112:1361-71. [PMID: 22267388 DOI: 10.1152/japplphysiol.01308.2011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
Abstract
To date, no studies have examined whether there are either sex- or ovarian hormone-related alterations in arterial baroreflex resetting and function during dynamic exercise. Thus we studied 16 young men and 18 young women at rest and during leg cycling at 50% heart rate (HR) reserve. In addition, 10 women were studied at three different phases of the menstrual cycle. Five-second pulses of neck pressure (NP) and neck suction (NS) from +40 to -80 Torr were applied to determine full carotid baroreflex (CBR) stimulus response curves. An upward and rightward resetting of the CBR function curve was observed during exercise in all groups with a similar magnitude of CBR resetting for mean arterial pressure (MAP) and HR between sexes (P > 0.05) and at different phases of the menstrual cycle (P > 0.05). For CBR control of MAP, women exhibited augmented pressor responses to NP at rest and exercise during mid-luteal compared with early and late follicular phases. For CBR control of HR, there was a greater bradycardic response to NS in women across all menstrual cycle phases with the operating point (OP) located further away from centering point (CP) on the CBR-HR curve during rest (OP-CP; in mmHg: -13 ± 3 women vs. -3 ± 3 men; P < 0.05) and exercise (in mmHg: -31 ± 2 women vs. -15 ± 3 men; P < 0.05). Collectively, these findings suggest that sex and fluctuations in ovarian hormones do not influence exercise resetting of the baroreflex. However, women exhibited greater CBR control of HR during exercise, specifically against acute hypertension, an effect that was present throughout the menstrual cycle.
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Affiliation(s)
- Areum Kim
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO 65212, USA
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Dipla K, Nassis GP, Vrabas IS. Blood Pressure Control at Rest and during Exercise in Obese Children and Adults. J Obes 2012; 2012:147385. [PMID: 22666555 PMCID: PMC3361254 DOI: 10.1155/2012/147385] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Revised: 02/19/2012] [Accepted: 03/01/2012] [Indexed: 11/17/2022] Open
Abstract
The hemodynamic responses to exercise have been studied to a great extent over the past decades, and an exaggerated blood pressure response during an acute exercise bout has been considered as an indicator of cardiovascular risk. Obesity is a major factor influencing the blood pressure response to exercise since evidence indicates that the arterial pressure response to exercise is exacerbated in obese compared with lean adults. Signs of augmented responses (such as an exaggerated blood pressure response) to physical exertion appear early in life (from the prepubertal years) in obese individuals. Understanding the mechanisms that drive the altered hemodynamic responses during exercise in obese individuals and prevent the progression to hypertension is vitally important. This paper focuses on the evidence linking obesity with alterations of the autonomic nervous system and discusses the potential mechanisms and consequences of the altered sympathetic nervous system behavior in obese individuals at rest and during exercise. Furthermore, this paper presents the alterations in the reflex regulatory mechanisms ("exercise pressor reflex" and baroreflex) in obese children and adults and addresses the effects of training on obesity-related disturbances.
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Affiliation(s)
- Konstantina Dipla
- Exercise Physiology and Biochemistry Laboratory, Department of Physical Education and Sport Sciences at Serres, Aristotle University of Thessaloniki, Agios Ioannis, 62110 Serres, Greece
- *Konstantina Dipla:
| | - George P. Nassis
- Department of Sport Medicine and Biology of Exercise, Faculty of Physical Education and Sport Science, University of Athens, 17237 Daphne, Greece
| | - Ioannis S. Vrabas
- Exercise Physiology and Biochemistry Laboratory, Department of Physical Education and Sport Sciences at Serres, Aristotle University of Thessaloniki, Agios Ioannis, 62110 Serres, Greece
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