keyword
MENU ▼
Read by QxMD icon Read
search

muscle sympathetic nerve activity

keyword
https://www.readbyqxmd.com/read/29220864/the-nature-of-catecholamine-containing-neurons-in-the-enteric-nervous-system-in-relationship-with-organogenesis-normal-human-anatomy-and-neurodegeneration
#1
G Natale, L Ryskalin, C L Busceti, F Biagioni, F Fornai
The gastrointestinal tract is provided with extrinsic and intrinsic innervation. The extrinsic innervation includes the classic vagal parasympathetic and sympathetic components, with afferent sensitive and efferent secretomotor fibers. The intrinsic innervations is represented by the enteric nervous system (ENS), which is recognized as a complex neural network controlling a variety of cell populations, including smooth muscle cells, mucosal secretory cells, endocrine cells, microvasculature, immune and inflammatory cells...
September 1, 2017: Archives Italiennes de Biologie
https://www.readbyqxmd.com/read/29212669/long-duration-bed-rest-modifies-sympathetic-neural-recruitment-strategies-in-males-and-females
#2
Stephen A Klassen, Steven De Abreu, Danielle K Greaves, Derek S Kimmerly, Philippe Arbeille, Pierre Denise, Richard L Hughson, Hervé Normand, J Kevin Shoemaker
To understand the impact of physical deconditioning with head-down tilt bed rest (HDBR) on the malleability of sympathetic discharge patterns, we studied a) baseline integrated muscle sympathetic nerve activity (MSNA; microneurography) from 13 females participating in the WISE-2005 60-day HDBR study (Female, retrospective analysis), b) integrated MSNA and multi-unit action potential (AP) analysis in 13 males (Male) performed on data collected at baseline and during physiological stress imposed by end-inspiratory apnea, in a new 60-day HDBR study, and c) a repeatability study (Control, n = 6, retrospective analysis, 4 weeks between tests)...
December 6, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/29207251/oral-contraceptives-modulate-the-muscle-metaboreflex-in-healthy-young-women
#3
Hanna R Parmar, Jasmin Sears, Yannick Molgat-Seon, Cara L McCulloch, Laura A McCracken, Courtney V Brown, Andrew William Sheel, Paolo B Dominelli
There are known sex-differences in blood pressure regulation. The differences are related to ovarian hormones that influence β-adrenergic receptors and the transduction of muscle sympathetic nerve activity. Oral contraceptives (OC) modulate the ovarian hormonal profile in women and therefore may alter the cardiovascular response. We questioned if OC would alter the absolute pressor response to static exercise and influence the day-to-day variability of the response. Healthy men (n=11) and women (n=19) completed a familiarization day and two experimental testing days...
December 5, 2017: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
https://www.readbyqxmd.com/read/29206785/three-weeks-of-overload-training-increases-resting-muscle-sympathetic-activity
#4
Alexandra M Coates, Anthony V Incognito, Jeremy D Seed, Connor J Doherty, Philip J Millar, Jamie F Burr
PURPOSE: Overload training is hypothesized to alter autonomic regulation, though interpretations using indirect measures of heart rate variability are conflicting. The aim of the present study was to examine the effects of overload training on muscle sympathetic nerve activity (MSNA), a direct measure of central sympathetic outflow, in recreational endurance athletes. METHODS: Measurements of heart rate variability, cardiac baroreflex sensitivity (BRS), MSNA (microneurography), and sympathetic BRS were obtained in seventeen healthy triathletes and cyclists after 1-week of reduced training (baseline) and following 3-weeks of either regular (CON, n=7) or overload (OL, n=10) training...
December 2, 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/29203629/exaggerated-vasoconstriction-to-spontaneous-bursts-of-muscle-sympathetic-nerve-activity-in-healthy-young-black-men
#5
Jennifer R Vranish, Seth W Holwerda, Benjamin E Young, Daniel P Credeur, Jordan C Patik, Thales C Barbosa, David M Keller, Paul J Fadel
Blacks have the highest prevalence of hypertension, putting them at greater risk of cardiovascular disease and death. Previous studies have reported that, relative to whites, healthy black men have augmented pressor responses to sympathoexcitatory stressors. Although important, these studies do not inform about the resting state and the influence of spontaneous changes in resting muscle sympathetic nerve activity (MSNA). Likewise, little is known about the transduction of MSNA into a vascular response at rest on a beat-to-beat basis...
December 4, 2017: Hypertension
https://www.readbyqxmd.com/read/29185161/exercise-therapy-and-autonomic-function-in-heart-failure-patients-a-systematic-review-and-meta-analysis
#6
REVIEW
M J Pearson, N A Smart
A large body of evidence exists indicating that autonomic imbalance is characteristic of heart failure, with several parameters of autonomic function associated with adverse clinical outcomes. The aim of this systematic review and meta-analysis was to investigate the effects of exercise training on parameters of autonomic function in patients with heart failure and where possible quantify the size of the effect. We conducted database searches (PubMed, EMBASE and Cochrane Trials Register to 31 March 2017) for exercise-based rehabilitation trials in heart failure; using search terms, exercise training, autonomic function, heart rate recovery, heart rate variability and muscle sympathetic nerve activity...
November 29, 2017: Heart Failure Reviews
https://www.readbyqxmd.com/read/29174521/influence-of-recent-altitude-exposure-on-sea-level-sympathetic-neural-hemodynamic-responses-to-orthostasis
#7
K M Mitchell, K E Bradbury, A M Posch, B A Beidleman, C S Fulco, S R Muza, N Charkoudian
Although it has been shown that muscle sympathetic nerve activity increases during high altitude exposure, mechanisms of sympathoexcitation and blood pressure control after return from altitude are not well described. We hypothesized that: (1) living for 12days at 4300m (Pikes Peak, Colorado) would result in increased muscle sympathetic nerve activity 24h after return to sea level; (2) post-Pikes Peak sympathetic neural and hemodynamic responses to orthostasis would be decreased due to a potential 'ceiling effect' on sympathetic activity; and (3) the magnitude of individual increases in sympathetic nerve activity post-Pikes Peak would be inversely related to baseline sympathetic nerve activity before traveling to altitude...
November 22, 2017: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/29151035/hypertension-in-obese-black-women-is-not-caused-by-increased-sympathetic-vascular-tone
#8
Alejandro Marinos, Alfredo Gamboa, Jorge E Celedonio, Brock A Preheim, Luis E Okamoto, Claudia E Ramirez, Amy C Arnold, Andre Diedrich, Italo Biaggioni, Cyndya A Shibao
BACKGROUND: Black women have one of the highest prevalence rates of hypertension and obesity in the United States. We previously reported that sympathetic activation induced by obesity is a significant contributor to hypertension in white patients. It is unknown whether sympathetic activity similarly contributes to hypertension in obese black women. METHODS AND RESULTS: We studied 42 obese women (16 white, body mass index 36±4 kg/m(2), 44% with hypertension; 26 black, body mass index 35±4 kg/m(2), 46% with hypertension)...
November 18, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/29142091/physiological-and-pathophysiological-firing-properties-of-single-postganglionic-sympathetic-neurons-in-humans
#9
Vaughan G Macefield, B Gunnar Wallin
It has long been known from microneurographic recordings in human subjects that activity of postganglionic sympathetic axons occurs as spontaneous bursts, with muscle sympathetic nerve activity (MSNA) exhibiting strong cardiac rhythmicity via the baroreflex and skin sympathetic nerve activity (SSNA) showing much weaker cardiac modulation. Here we review the firing properties of single sympathetic neurons, obtained using highly selective microelectrodes. Individual vasoconstrictor neurons supplying muscle or skin, or sudomotor neurones supplying sweat glands, always discharge with a low firing probability (~30%) and at very low frequencies (~0...
November 15, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/29131007/proteinase-activated-receptor-2-sensitivity-of-amplified-trpa1-activity-in-skeletal-muscle-afferent-nerves-and-exercise-pressor-reflex-in-rats-with-femoral-artery-occlusion
#10
Jihong Xing, Jianhua Li
BACKGROUND/AIMS: Limb ischemia occurs in peripheral artery disease (PAD). Sympathetic nerve activity (SNA) that regulates blood flow directed to the ischemic limb is exaggerated during exercise in this disease, and transient receptor potential channel A1 (TRPA1) in thin-fiber muscle afferents contributes to the amplified sympathetic response. The purpose of the present study was to determine the role of proteinase-activated receptor-2 (PAR2) in regulating abnormal TRPA1 function and the TRPA1-mediated sympathetic component of the exercise pressor reflex...
November 6, 2017: Cellular Physiology and Biochemistry
https://www.readbyqxmd.com/read/29123236/induction-of-glucose-uptake-in-skeletal-muscle-by-central-leptin-is-mediated-by-muscle-%C3%AE-2-adrenergic-receptor-but-not-by-ampk
#11
Tetsuya Shiuchi, Chitoku Toda, Shiki Okamoto, Eulalia A Coutinho, Kumiko Saito, Shinji Miura, Osamu Ezaki, Yasuhiko Minokoshi
Leptin increases glucose uptake and fatty acid oxidation (FAO) in red-type skeletal muscle. However, the mechanism remains unknown. We have investigated the role of β2-adrenergic receptor (AR), the major β-AR isoform in skeletal muscle, and AMPK in leptin-induced muscle glucose uptake of mice. Leptin injection into the ventromedial hypothalamus (VMH) increased 2-deoxy-D-glucose (2DG) uptake in red-type skeletal muscle in wild-type (WT) mice accompanied with increased phosphorylation of the insulin receptor (IR) and Akt as well as of norepinephrine (NE) turnover in the muscle...
November 9, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29118201/inflow-of-oxygen-and-glucose-into-brain-tissue-induced-by-intravenous-norepinephrine-relationships-with-central-metabolic-and-peripheral-vascular-responses
#12
R Aaron Bola, Eugene A Kiyatkin
As an essential part of sympathetic activation that prepares the organism for "fight or flight," peripheral norepinephrine (NE) plays an important role in regulating cardiac activity and the tone of blood vessels, increasing blood flow to the heart and the brain and decreasing blood flow to the organs not as necessary for immediate survival. To assess whether this effect is applicable to the brain, we used high-speed amperometry to measure the changes in nucleus accumbens (NAc) levels of oxygen and glucose induced by intravenous (iv) injections of NE in awake, freely-moving rats...
November 8, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/29114523/skeletal-muscle-contraction-induced-vasodilation-in-the-microcirculation
#13
REVIEW
Kwang-Seok Hong, Kijeong Kim
Maximal whole body exercise leads skeletal muscle blood flow to markedly increase to match metabolic demands, a phenomenon termed exercise hyperaemia that is accomplished by increasing vasodilation. However, local vasodilatory mechanisms in response to skeletal muscle contraction remain uncertain. This review highlights metabolic vasodilators released from contracting skeletal muscle, endothelium, or blood cells. As a considerable skeletal muscle vasodilation potentially results in hypotension, sympathetic nerve activity needs to be augmented to elevate cardiac output and blood pressure during dynamic exercise...
October 2017: Journal of Exercise Rehabilitation
https://www.readbyqxmd.com/read/29070505/inter-individual-variability-in-muscle-sympathetic-responses-to-static-handgrip-in-young-men-evidence-for-sympathetic-responder-types
#14
Anthony V Incognito, Connor J Doherty, Jordan B Lee, Matthew J Burns, Philip J Millar
Negative and positive muscle sympathetic nerve activity (MSNA) responders have been observed during mental stress. We hypothesized that similar MSNA response patterns could be identified during the first minute of static handgrip and contribute to the inter-individual variability throughout exercise. Supine measurements of multi-unit MSNA (microneurography) and continuous blood pressure (Finometer) were recorded in 29 young healthy men during the first (HG1) and second (HG2) minute of static handgrip (30% maximal voluntary contraction) and subsequent post-exercise circulatory occlusion (PECO)...
October 25, 2017: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/29054973/chronic-femoral-artery-ligation-exaggerates-the-pressor-and-sympathetic-nerve-responses-during-dynamic-skeletal-muscle-stretch-in-decerebrate-rats
#15
Evan A Kempf, Korynne S Rollins, Tyler D Hopkins, Alec L Butenas, Joseph M Santin, Joshua R Smith, Steven W Copp
Mechanical and metabolic signals arising during skeletal muscle contraction reflexly increase sympathetic nerve activity and blood pressure (i.e., the exercise pressor reflex). In a rat model of simulated peripheral artery disease (PAD) in which a femoral artery is chronically (~72 hours) ligated, the mechanically-sensitive component of the exercise pressor reflex during 1 Hz dynamic contraction is exaggerated compared to that found in normal rats. Whether this is due to an enhanced acute sensitization of mechanoreceptors by metabolites produced during contraction or involves a chronic sensitization of mechanoreceptors is unknown...
October 20, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/29040222/neurovascular-response-during-exercise-and-mental-stress-in-anabolic-steroid-users
#16
Rafael Armani Porello, Marcelo Rodrigues Dos Santos, Francis Ribeiro de Souza, Guilherme Wesley Peixoto da Fonseca, Ana Luiza Carrari Sayegh, Tiago Franco de Oliveira, César Abreu Akiho, Maurício Yonamine, Rosa Maria Rodrigues Pereira, Carlos Eduardo Negrão, Maria-Janieire de Nazaré Nunes Alves
PURPOSE: Increased resting muscle sympathetic nerve activity (MSNA) and lower forearm blood flow (FBF) were observed in young men who use anabolic androgenic steroids (AAS). However, the response of MSNA and FBF in AAS users triggered by muscle mechanoreflex and central command has never been tested. Additionally, we evaluated the blood pressure (BP) and heart rate (HR) responses during these maneuvers. METHODS: Nineteen AAS users (AASU) aged 31±6 yr and 18 AAS nonusers (AASNU) aged 29±4 yr were recruited...
October 16, 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/29034524/carotid-chemoreceptor-control-of-muscle-sympathetic-nerve-activity-in-hypobaric-hypoxia
#17
James P Fisher, Daniela Flück, Matthias P Hilty, Carsten Lundby
High altitude hypoxia causes pronounced sympathoexcitation but the underlying mechanisms remain unclear. We tested the hypothesis that intravenous infusion of dopamine to attenuate carotid chemoreceptor responsiveness would reduce muscle sympathetic nerve activity (MSNA) at high altitude. Nine healthy individuals (mean [SD]; 26 [4] yr) were studied at sea level (SL, Zurich) and at high altitude (ALT, 3454 m, 15-17 days after arrival), both while breathing the ambient air and during an acute incremental hypoxia test (8 × 3 min stages, PET O2 90-45 mmHg)...
October 15, 2017: Experimental Physiology
https://www.readbyqxmd.com/read/28982333/cerebral-artery-vasoconstriction-is-endothelin-1-dependent-requiring-neurogenic-and-adrenergic-crosstalk
#18
Roel H L Haeren, Sieuwke A Hartmans, Jo De Mey, Govert Hoogland, Jim Dings, Olaf E M G Schijns, Sander M J van Kuijk, Kim Rijkers, Paul Schiffers, Koo J van Overbeeke
BACKGROUND: The regulation of cerebral arterial vasomotor tone involves several mechanisms. The role of sympathetic nerves and the adrenergic neurotransmitter, noradrenaline (NA), has been subject of debate for decades. Moreover, the specific role of endothelin-1 (ET-1) in cerebral arterial vasoconstriction has not been elucidated to date. In this study, we evaluated the contribution of NA and ET-1 to cerebral artery vasoconstriction. METHODS: Arterial responses of rat middle cerebral arteries, and human pial cerebral arteries to cumulative concentrations of NA and ET-1, and to electrical field stimulation (EFS), were evaluated...
October 5, 2017: Current Neurovascular Research
https://www.readbyqxmd.com/read/28970198/sympathetic-neural-reactivity-to-mental-stress-differs-in-black-and-non-hispanic-white-adults
#19
Ida T Fonkoue, Christopher E Schwartz, Min Wang, Jason R Carter
Black adults have a higher risk of hypertension compared to non-Hispanic white (NHW) adults, but physiological mechanisms underlying this predisposition remain unclear. This study compared muscle sympathetic nerve activity (MSNA) responses to mental stress in a group of young black and NHW participants. We hypothesized that the sympathoexcitation associated with mental stress would be greater in black adults compared to NHW. Thirty-five male adults (19 black, 23±1 years; 16 NHW, 22±1 years) were examined during a 5 min supine baseline and 5 min of mental stress (via mental arithmetic)...
September 28, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28966594/the-role-of-the-autonomic-nervous-system-in-the-pathophysiology-of-obesity
#20
REVIEW
Daniela Guarino, Monica Nannipieri, Giorgio Iervasi, Stefano Taddei, Rosa Maria Bruno
Obesity is reaching epidemic proportions globally and represents a major cause of comorbidities, mostly related to cardiovascular disease. The autonomic nervous system (ANS) dysfunction has a two-way relationship with obesity. Indeed, alterations of the ANS might be involved in the pathogenesis of obesity, acting on different pathways. On the other hand, the excess weight induces ANS dysfunction, which may be involved in the haemodynamic and metabolic alterations that increase the cardiovascular risk of obese individuals, i...
2017: Frontiers in Physiology
keyword
keyword
54083
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"