scholarly journals Peripheral pre-synaptic pathway reduces the heart rate response to sympathetic activation following exercise training: role of NO

2000 ◽  
Vol 47 (1) ◽  
pp. 90-98 ◽  
Author(s):  
R Mohan
Keyword(s):  
Heart Rate ◽  
Exercise Training ◽  
Heart Rate Response ◽  
Sympathetic Activation

Effect of human galanin on the response of circulating catecholamines to hypoglycemia in man

1995 ◽  
Vol 133 (6) ◽  
pp. 723-728 ◽  
Author(s):  
Ettore C degli Uberti ◽  
Maria R Ambrosio ◽  
Marta Bondanelli ◽  
Giorgio Transforini ◽  
Alberto Valentini ◽  
...  
Keyword(s):  
Heart Rate ◽  
Healthy Subjects ◽  
Sympathetic Nerve Activity ◽  
Heart Rate Response ◽  
Statistical Significance ◽  
Inhibitory Effect ◽  
Amino Acid Residues ◽  
Nerve Activity ◽  
Receptor Stimulation

degli Uberti EC, Ambrosio MR, Bondanelli M, Trasforini G, Valentini A, Rossi R, Margutti A, Campo M. Effect of human galanin on the response of circulating catecholamines to hypoglycemia in man. Eur J Endocrinol 1995;133:723–8. ISSN 0804–4643 Human galanin (hGAL) is a neuropeptide with 30 amino acid residues that has been found in the peripheral and central nervous system, where it often co-exists with catecholamines. In order to clarify the possible role of hGAL in the regulation of sympathoadrenomedullary function, the effect of a 60 min infusion of hGAL (80 pmol·kg−1 · min−1) on plasma epinephrine and norepinephrine responses to insulin-induced hypoglycemia in nine healthy subjects was investigated. Human GAL administration significantly reduced both the release of basal norepinephrine and the response to insulin-induced hypoglycemia, whereas it attenuated the epinephrine response by 26%, with the hGAL-induced decrease in epinephrine release failing to achieve statistical significance. Human GAL significantly increased the heart rate in resting conditions and clearly exaggerated the heart rate response to insulin-induced hypoglycemia, whereas it had no effect on the blood pressure. We conclude that GAL receptor stimulation exerts an inhibitory effect on basal and insulin-induced hypoglycemia-stimulated release of norepinephrine. These findings provide further evidence that GAL may modulate sympathetic nerve activity in man but that it does not play an important role in the regulation of adrenal medullary function. Ettore C degli Uberti, Chair of Endocrinology, University of Ferrara, Via Savonarola 9, I-44100 Ferrara, Italy

Central nervous system control of cardiorespiratory nasopharyngeal reflexes in the rabbit

1975 ◽  
Vol 228 (2) ◽  
pp. 404-409 ◽  
Author(s):  
S White ◽  
RJ McRitchie ◽  
PI Korner
Keyword(s):  
Heart Rate ◽  
Heart Rate Response ◽  
Carotid Sinus ◽  
Cerebral Hemispheres ◽  
System Control ◽  
Controlled Ventilation ◽  
Cardiovascular Reflex ◽  
Respiratory Reflex ◽  
Central Nervous System Control

The role of different central nervous regions in the reflex apnea, bradycardia, and mesenteric vasoconstriction evoked by nasopharyngeal stimulation with cigarette smoke was examined in unanesthetized shamoperated, thalamic, and pontine rabbits with intact and sectioned carotid sinus and aortic nerves (CS and AN). Apnea occurred in all preparations. In pontine animals with intact CS and AN, the heart rate response was reduced but not the mesenteric vasoconstriction. The role of suprabulbar and bulbospinal regions became more apparent when individual components of the input profile were examined in animals with controlled ventilation. The bradycardia and mesenteric vasoconstriction evoked by apnea without smoke, but not by smoke without apnea, were reduced in pontine animals. Prior section of the CS and AN attenuated the response in all neural preparations but to the least extent when cerebral hemispheres were intact. The data indicate that the respiratory reflex is predominantly integrated at bulbospinal sites, but the cardiovascular reflex is integrated at both bulbospinal and suprabulbar sites, or is integrated at bulbospinal and modulated from suprabulbar sites.

Characterization of the role of endogenous nitric oxide in myogenic vascular oscillations during cooling-evoked hemodynamic perturbations of rats

2017 ◽  
Vol 95 (7) ◽  
pp. 803-810 ◽  
Author(s):  
Yi-Hsien Lin ◽  
Yia-Ping Liu ◽  
Yu-Chieh Lin ◽  
Po-Lei Lee ◽  
Che-Se Tung
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Heart Rate ◽  
Cold Stress ◽  
Low Frequency ◽  
Sympathetic Activation ◽  
Nitric Oxide Synthase Inhibitor ◽  
Dicrotic Notch ◽  
Endogenous Nitric Oxide

Rapid immersion of a rat’s limbs into 4 °C water, a model of cold stress, can elicit hemodynamic perturbations (CEHP). We previously reported that CEHP is highly relevant to sympathetic activation and nitric oxide production. This study identifies the role of nitric oxide in CEHP. Conscious rats were pretreated with the nitric oxide synthase inhibitor L-NAME (NG-nitro-l-arginine methyl ester) alone or following the removal of sympathetic influences using hexamethonium or guanethidine. Rats were then subjected to a 10 min cold-stress trial. Hemodynamic indices were telemetrically monitored throughout the experiment. The analyses included measurements of systolic blood pressure; heart rate; dicrotic notch; short-term cardiovascular oscillations and coherence between blood pressure variability and heart rate variability in regions of very low frequency (0.02–0.2 Hz), low frequency (0.2–0.6 Hz), and high frequency (0.6–3.0 Hz). We observed different profiles of hemodynamic reaction between hexamethonium and guanethidine superimposed on L-NAME, suggesting an essential role for a functional adrenal medulla release of epinephrine under cold stress. These results indicate that endogenous nitric oxide plays an important role in the inhibition of sympathetic activation and cardiovascular oscillations in CEHP.

scholarly journals THE ROLE OF β, α1 AND α2-ADRENO RECEPTORS IN THE REGULATION OF THE HEART RATE OF LABORATORY ANIMALS EXPOSED TO VARIOUS MODES OF MOTOR ACTIVITY

2021 ◽  
Vol 248 (4) ◽  
pp. 291-296
Author(s):  
A.V. Shigapova ◽  
◽  
I.Kh. Vakhitov ◽  
R.S. Safin ◽  
I.R. Ibatullin ◽  
...  
Keyword(s):  
Heart Rate ◽  
Motor Activity ◽  
Heart Rate Response ◽  
Laboratory Animals ◽  
Initial Reaction ◽  
Muscle Training ◽  
Pronounced Decrease ◽  
Motor Mode ◽  
First Time

For the first time, studies were conducted to study the features of the heart rate response of laboratory animals exposed to various modes of motor activity when administered with β, α1 and α2-blockers. It was found that in all the experimental groups of animals studied, a decrease in the heart rate response was observed in the first week after the introduction of β, α1 and α2-adreno blockers. It was revealed that the initial reaction of the heart rate on the introduction of β, α1 and α2-blockers depends on the level of motor activity of laboratory animals. It was found that the most pronounced decrease in the heart rate response to the introduction of different subtypes of adreno-blockers is observed in the group of animals with limited motor activity. At the same time, the smallest decrease in the heart rate response occurs in the group of animals subject to enhanced motor mode. It was revealed that in the group of experimental animals, during further muscle training, by the end of the fourth week, there was a less pronounced decrease in the heart rate response to the administration of β, α1 and α2-adreno blockers. It was found that in a group of animals subject to a regime of limited motor activity, by the end of the fourth week of hypokinesia, the most pronounced decrease in the heart rate response to the introduction of β, α1-targeted blockers occurs.

Heart Rate Response and Recovery after Exercise Training in Elderly Patients with Diastolic Heart Failure

2007 ◽  
Vol 39 (Supplement) ◽  
pp. S32
Author(s):  
Sara Maldonado-Martín ◽  
Peter H. Brubaker ◽  
Brian Moore ◽  
Dalane W. Kitzman
Keyword(s):  
Heart Failure ◽  
Heart Rate ◽  
Exercise Training ◽  
Elderly Patients ◽  
Heart Rate Response ◽  
Diastolic Heart Failure ◽  
Response And Recovery

Cardiac function and exercise training in conscious dogs

1977 ◽  
Vol 42 (6) ◽  
pp. 824-832 ◽  
Author(s):  
H. L. Stone
Keyword(s):  
Heart Rate ◽  
Exercise Training ◽  
Cardiac Function ◽  
Heart Rate Response ◽  
Exercise Program ◽  
Left Ventricular Pressure ◽  
Left Ventricular ◽  
Ventricular Pressure ◽  
Time Intervals ◽  
Similar Time

Exercise training (T) was accomplished in 21 mongrel dogs. The animals were instrumented to measure ascending aortic flow, left ventricular pressure, and left atrial pressure. They were allowed to recover for 4 wk following surgery before accomplishing a standardized submaximal test (SMT). The exercise program alternated daily between sprint and endurance training. During T, the animals were tested while lying quietly on a laboratory table as well as during the SMT. In six animals, ventricular function curves (VFC) were obtained by rapid volume loading at similar time intervals as the SMT. Heart rate increased during the SMT but was found to be reduced in the T animals by an average of 20 beats/min. The maximum derivative of left ventricular pressure (P) increased during the SMT in T animals by an average of 2,200 Torr/s above the untrained animals. The VFC was lower in T animals than untrained animals because of a reduction in heart rate response. Results indicate a reflex adaptation of the nervous system with training to improve cardiac function.

Role of the carotid bodies in the heart rate response to breath holding in man

1976 ◽  
Vol 41 (3) ◽  
pp. 336-340 ◽  
Author(s):  
P. M. Gross ◽  
B. J. Whipp ◽  
J. T. Davidson ◽  
S. N. Koyal ◽  
K. Wasserman
Keyword(s):  
Heart Rate ◽  
Heart Rate Response ◽  
Normal Subjects ◽  
The Other ◽  
Breath Holding ◽  
Asthmatic Patients ◽  
Carotid Bodies ◽  
Normal Man

To investigate the role of the carotid bodies in regulating the bradycardia of breath holding in man, we studied heart rate (HR) responses to prolonged breath holding (BH) in five asymptomatic asthmatic patients whose carotid bodies had been resected (CBR). Seven normal subjects served as controls. BH experiments were randomly initiated with single breaths of 100%, 21%,or 12% 92. During BH with 21% O2, normal subjects displayed the typical bradycardia; this response, however, was attenuated with the other O2 concentrations. In contrast, the CBR subjects manifested BH tachycardia which was inversely proportional to the O2 tension. HR increased in be CBR group by 5%, 31%, and 45% during BH with 100%, 21%, and 12% O2, respectively. These results demonstrate that the bradycardia of BH in normal man is under the influence of the carotid bodies. During BH and in the absence of carotid bodies, an O2 tension-dependent tachycardia is unveiled.

scholarly journals Weight Loss and Exercise Training Effect on Oxygen Uptake and Heart Rate Response to Locomotion

2012 ◽  
Vol 26 (5) ◽  
pp. 1366-1373 ◽  
Author(s):  
Gary R. Hunter ◽  
Gordon Fisher ◽  
David R. Bryan ◽  
Paul A. Zuckerman
Keyword(s):  
Heart Rate ◽  
Weight Loss ◽  
Exercise Training ◽  
Oxygen Uptake ◽  
Heart Rate Response ◽  
Training Effect
Sign in / Sign up

Export Citation Format

Share Document