scholarly journals Differential cardiovascular responses to cutaneous afferent subtypes in a nociceptive intersegmental spinal reflex

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Hyun Joon Lee ◽  
Jason M. White ◽  
Jumi Chung ◽  
Patrick Malone ◽  
Stephen P. DeWeerth ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Electrical Stimulation ◽  
Cardiovascular Responses ◽  
Stimulation Frequency ◽  
Spinal Reflex ◽  
Afferent Stimulation ◽  
C Fibers ◽  
Nociceptive Afferents ◽  
The Relationship

AbstractElectrical stimulation to segmental dorsal cutaneous nerves (DCNs) activates a nociceptive sensorimotor reflex and the same afferent stimulation also evokes blood pressure (BP) and heart rate (HR) responses in rats. To investigate the relationship between those cardiovascular responses and the activation of nociceptive afferents, we analyzed BP and HR responses to electrical stimulations at each DCN from T6 to L1 at 0.5 mA to activate A-fiber alone or 5 mA to activate both A- and C-fibers at different frequencies. Evoked cardiovascular responses showed a decrease and then an increase in BP and an increase and then a plateau in HR. Segmentally, both cardiovascular responses tended to be larger when evoked from the more rostral DCNs. Stimulation frequency had a larger effect on cardiovascular responses than the rostrocaudal level of the DCN input. Stimulation strength showed a large effect on BP changes dependent on C-fibers whereas HR changes were dependent on A-fibers. Additional A-fiber activation by stimulating up to 4 adjacent DCNs concurrently, but only at 0.5 mA, affected HR but not BP. These data support that cutaneous nociceptive afferent subtypes preferentially contribute to different cardiovascular responses, A-fibers to HR and C-fibers to BP, with temporal (stimulation frequency) and spatial (rostrocaudal level) dynamics.

scholarly journals The influence of low-intensity resistance training combined with neuromuscular electrical stimulation on autonomic activity in healthy adults: A randomized controlled cross-over trial

2020 ◽  
pp. 1-9
Author(s):  
Toshiki Kutsuna ◽  
Hitoshi Sugawara ◽  
Hideaki Kurita ◽  
Satomi Kusaka ◽  
Tetsuya Takahashi
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Electrical Stimulation ◽  
Neuromuscular Electrical Stimulation ◽  
Cardiovascular Responses ◽  
Healthy Adults ◽  
Autonomic Activity ◽  
Low Intensity ◽  
Randomized Controlled

Background: Low-intensity resistance training (RT) combined with neuromuscular electrical stimulation (NMES) is one method of exercise to improve the deterioration of physical function. However, it is unclear whether low-intensity RT combined with NMES (RT + NMES) can be safely implemented. Objective: This study aimed to examine the influence of low-intensity RT + NMES on autonomic activity and cardiovascular responses in healthy adults. Methods: This study was an open-label, randomized controlled cross-over trial. The exercise intensity of isometric knee extension RT was set to 40% of the maximum voluntary contraction (peak torque). NMES was adjusted to a biphasic asymmetrical waveform with the frequency maintained at 50 Hz and a phase duration of 300 [Formula: see text]s. The difference in the change in autonomic activity and cardiovascular responses was compared by assessing heart rate variability, blood pressure, and heart rate during RT and [Formula: see text]. Results: Twenty healthy male college students (mean age [Formula: see text] years) participated in this study. The ratio of low- and high-frequency components of heart rate variability, systolic blood pressure, and heart rate increased during exercise in the RT and [Formula: see text] sessions ([Formula: see text]). There were no significant differences in autonomic activity and cardiovascular responses throughout the sessions during RT and [Formula: see text]. Conclusion: In conclusion, our results demonstrated that low-intensity [Formula: see text] was safe and did not induce excessive autonomic and cardiovascular responses in healthy adults.

Aging, isometric strength and endurance, and cardiovascular responses to static effort

1975 ◽  
Vol 38 (1) ◽  
pp. 91-95 ◽  
Author(s):  
J. S. Petrofsky ◽  
A. R. Lind
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Muscular Strength ◽  
Handgrip Strength ◽  
Cardiovascular Responses ◽  
Static Effort ◽  
Younger Men ◽  
Blood Pressures ◽  
Relationship Of ◽  
The Relationship

Previous studies on the relationship of age to isometric muscular strength are few, on isometric endurance rare, and on the physiological responses to static effort nonexistent. This investigation assessed the maximal handgrip strength, the duration of a fatiguing handgrip contraction at a tension of 40% of maximal strength and the heart rate and blood pressure during that contraction of 100 men aged from 22 to 62 yr. The subjects of this study were all men employed in a machine shop for a large aircraft corporation. The homogeneity of their occupations may well explain why, unlike previous reports, we found no change in muscular strength or muscular endurance with age. However, although heart rate increased during the contraction in all subjects, the increase in heart rate was greater in younger men. In contrast, while both systolic and diastolic blood pressures increased during the contraction in all subjects, the largest increase in systolic blood pressure was attained by the men in the older decades; there was no difference due to age in the diastolic blood pressures. The implications of these findings are discussed.

Cardiovascular Responses to Muscle Stretching: A Systematic Review and Meta-analysis

2021 ◽  
Author(s):  
Ewan Thomas ◽  
Marianna Bellafiore ◽  
Ambra Gentile ◽  
Antonio Paoli ◽  
Antonio Palma ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Vascular Function ◽  
Meta Analysis ◽  
Random Effect ◽  
Cardiovascular Responses ◽  
Qualitative Description ◽  
Cross Sectional ◽  
Quantitative Synthesis

AbstractThe aim of this study will be to review the current body of literature to understand the effects of stretching on the responses of the cardiovascular system. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching on responses of the cardiovascular system were investigated. Outcomes regarded heart rate(HR), blood pressure, pulse wave velocity (PWV of which baPWV for brachial-ankle and cfPWV for carotid-femoral waveforms), heart rate variability and endothelial vascular function. Subsequently, the effects of each outcome were quantitatively synthetized using meta-analytic synthesis with random-effect models. A total of 16 studies were considered eligible and included in the quantitative synthesis. Groups were also stratified according to cross-sectional or longitudinal stretching interventions. Quality assessment through the NHLBI tools observed a “fair-to-good” quality of the studies. The meta-analytic synthesis showed a significant effect of d=0.38 concerning HR, d=2.04 regarding baPWV and d=0.46 for cfPWV. Stretching significantly reduces arterial stiffness and HR. The qualitative description of the studies was also supported by the meta-analytic synthesis. No adverse effects were reported, after stretching, in patients affected by cardiovascular disease on blood pressure. There is a lack of studies regarding vascular adaptations to stretching.

Cardiovascular responses to head-stand posture

1963 ◽  
Vol 18 (5) ◽  
pp. 987-990 ◽  
Author(s):  
Shanker Rao
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
High Pressure ◽  
Blood Flow ◽  
Arterial Pressure ◽  
Skin Temperature ◽  
Cardiovascular Responses ◽  
Posterior Tibial Artery ◽  
Nervous Control ◽  
Posterior Tibial

Reports of cardiovascular responses to head-stand posture are lacking in literature. The results of the various responses, respectively, to the supine, erect, and head-stand posture, are as follows: heart rate/min 67, 84, and 69; brachial arterial pressure mm Hg 92, 90, and 108; posterior tibial arterial pressure mm Hg 98, 196, and 10; finger blood flow ml/100 ml min 4.5, 4.4, and 5.2; toe blood flow ml/100 ml min 7.1, 8.1, and 3.4; forehead skin temperature C 34.4, 34.0 and 34.3; dorsum foot skin temperature C 28.6, 28.2, and 28.2. It is inferred that the high-pressure-capacity vessels between the heart level and posterior tibial artery have little nervous control. The high-pressure baroreceptors take active part in postural adjustments of circulation. The blood pressure equating mechanism is not as efficient when vital tissues are pooled with blood as when blood supply to them is reduced. man; heart rate; blood flow; skin temperature Submitted on January 3, 1963

scholarly journals Tai-chi-chuan and yoga onpostexercise hypotension: comparison to aerobic and resistance exercise

2016 ◽  
Vol 29 (3) ◽  
pp. 543-552
Author(s):  
João Douglas Alves ◽  
Jorge Luiz de Brito Gomes ◽  
Caio Victor Coutinho de Oliveira ◽  
José Victor de Miranda Henriques Alves ◽  
Fabiana Ranielle de Siqueira Nogueira ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Young Women ◽  
Tai Chi ◽  
Cardiovascular Effects ◽  
Cardiovascular Responses ◽  
Tai Chi Chuan ◽  
Post Exercise ◽  
Significant Difference ◽  
Apparently Healthy

Abstract Introduction: Tai-Chi-Chuan and Yoga have becoming popular practices. However is unclear the cardiovascular effects, and if they present similar behavior to aerobic and resistance sessions. Objective: To evaluate the cardiovascular responses during the session and post-exercise hypotension (PEH) of Tai Chi Chuan (TS) and Yoga (YS) in comparison to aerobic (AS) and resistance (SR) exercises. Methods: Fourteen young women (22.3 ± 2 years) apparently healthy performed four sessions (AS, RS, TS and YS). The heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP) were recorded at resting, during (every 10 minutes) and until 50 minutes of recovery. Results: AS, RS, TS e YS showed significant increase in HR compared to resting.AS at 10, 30 e 50 minutes in relation to RS, TS e YS. The RS in relation to TS and YS at 10, 30 and 50 minutes. No significant difference between TS and YS. SBP was significantly increased in AS, RS, TS e YS at 10, 30 e 50 minutes during the session, in relation to rest. AS was significantly higher at 30 e 50 minutes than RS and higher than TS and YS at 10, 30 e 50 minutes. No significant difference in DBP. For PEH, AS, RS and TS significantly reduced at 10, 30 and 50 minutes. YS reduced at 50 minutes. No significant diastolic PEH. Conclusion: TS and YS showed as safe alternatives of exercising in the normotensive young adult woman, despite having lower values, they promote similar hemodynamic behavior to AS and RS.

Ascending pathways mediating somatoautonomic reflexes in exercising dogs

1987 ◽  
Vol 62 (3) ◽  
pp. 1186-1191 ◽  
Author(s):  
J. W. Kozelka ◽  
G. W. Christy ◽  
R. D. Wurster
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Surgical Techniques ◽  
Arterial Occlusion ◽  
Cardiovascular Responses ◽  
Spinal Pathways ◽  
Arterial Blood ◽  
Bilateral Carotid ◽  
Dorsolateral Funiculus ◽  
Carotid Arterial

The ascending spinal pathways mediating somatocardiovascular reflexes during exercise were studied in unanesthetized dogs by placing lesions in the lumbar spinal cord. After training to run on a treadmill with hindlimbs only, 20 dogs were anesthetized and instrumented using sterile surgical techniques. To chronically record heart rate and arterial blood pressure, the aorta was cannulated via the omocervical artery. To test the intactness of descending spinal sympathetic pathways, reflex pressor responses to baroreceptor hypotension were produced by bilateral carotid arterial occlusion using pneumatic vessel occluders placed around the common carotid arteries. To generate transient ischemic exercise (120 s), a pneumatic occluder was placed around the left iliac artery. Eight to 10 days after instrumentation, blood pressure and heart rate were monitored at rest and during hindlimb running with and without simultaneous iliac arterial occlusion. The modest pressor response and tachycardia elicited by hindlimb exercise were markedly augmented by simultaneous hindlimb ischemia (i.e., iliac arterial occlusion). Lesion placement in the dorsolateral sulcus area and the dorsolateral funiculus at L2 significantly reduced the blood pressure and heart rate responses to simultaneous exercise occlusion. The cardiovascular responses to nonischemic exercise and bilateral carotid arterial occlusion were not altered by such spinal sections. It is concluded that in the dog the ascending spinal pathways mediating cardiovascular responses to ischemic exercise are located in the lateral funiculus, including the dorsolateral sulcus area and dorsolateral funiculus.

Reciprocal rat chromosome 2 congenic strains reveal contrasting blood pressure and heart rate QTL

2002 ◽  
Vol 10 (3) ◽  
pp. 199-210 ◽  
Author(s):  
Adamu Alemayehu ◽  
Laura Breen ◽  
Drahomira Krenova ◽  
Morton P. Printz
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Spontaneously Hypertensive Rat ◽  
Cardiovascular Responses ◽  
Chromosome 2 ◽  
Spontaneously Hypertensive ◽  
Congenic Strains ◽  
Multiple Blood ◽  
Wistar Kyoto ◽  
Chromosome Segments

Evidence exists implying multiple blood pressure quantitative trait loci (QTL) on rat chromosome 2. To examine this possibility, four congenic strains and nine substrains were developed with varying size chromosome segments introgressed from the spontaneously hypertensive rat (SHR/lj) and normotensive Wistar-Kyoto rat (WKY/lj) onto the reciprocal genetic background. Cardiovascular phenotyping was conducted with telemetry over extended periods during standard salt (0.7%) and high-salt (8%) diets. Our results are consistent with at least three independent pressor QTL: transfer of SHR/lj alleles to WKY/lj reveals pressor QTL within D2Rat21-D2Rat27 and D2Mgh10-D2Rat62, whereas transfer of WKY/lj D2Rat161-D2Mit8 to SHR/lj reveals a depressor locus. Our results also suggest a depressor QTL in SHR/lj located within D2Rat161-D2Mgh10. Introgressed WKY/lj segments also reveal a heart rate QTL within D2Rat40-D2Rat50 which abolished salt-induced bradycardia, dependent upon adjoining SHR/lj alleles. This study confirms the presence of multiple blood pressure QTL on chromosome 2. Taken together with our other studies, we conclude that rat chromosome 2 is rich in alleles for cardiovascular and behavioral traits and for coordinated coupling between behavior and cardiovascular responses.

Acute Cardiovascular Responses to Self-selected Intensity Exercise in Parkinson's Disease

2021 ◽  
Author(s):  
Hélcio Kanegusuku ◽  
Gabriel Grizzo Cucato ◽  
Paulo Longano ◽  
Erika Okamoto ◽  
Maria Elisa Pimentel Piemonte ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Parkinson’S Disease ◽  
Heart Rate ◽  
Parkinson's Disease ◽  
Pulse Wave ◽  
Augmentation Index ◽  
Cardiovascular Responses ◽  
Cycle Ergometer ◽  
Control Session ◽  
Wave Analysis

AbstractParkinson’s disease patients frequently present cardiovascular dysfunction. Exercise with a self-selected intensity has emerged as a new strategy for exercise prescription aiming to increase exercise adherence. Thus, the current study evaluated the acute cardiovascular responses after a session of aerobic exercise at a traditional intensity and at a self-selected intensity in Parkinson’s disease patients. Twenty patients (≥ 50 years old, Hoehn & Yahr 1–3 stages) performed 3 experimental sessions in random order: Traditional session (cycle ergometer, 25 min, 50 rpm, 60–80% maximum heart rate); Self-selected intensity: (cycle ergometer, 25 min, 50 rpm with self-selected intensity); and Control session (resting for 25 min). Before and after 30 min of intervention, brachial and central blood pressure (auscultatory method and pulse wave analysis, respectively), cardiac autonomic modulation (heart rate variability), and arterial stiffness (pulse wave analysis) were evaluated. Brachial and central systolic and diastolic blood pressure, heart rate, and the augmentation index increased after the control session, whereas no changes were observed after the exercise sessions (P<0.01). Pulse wave velocity and cardiac autonomic modulation parameters did not change after the three interventions. In conclusion, a single session of traditional intensity or self-selected intensity exercises similarly blunted the increase in brachial and central blood pressure and the augmentation index compared to a non-exercise control session in Parkinson’s disease patients.

Interaction of aortic and carotid sinus baroreceptors: effect of activation times

1975 ◽  
Vol 228 (1) ◽  
pp. 238-243 ◽  
Author(s):  
PG Katona ◽  
KS Tan
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Electrical Stimulation ◽  
Pulse Wave Velocity ◽  
Wave Velocity ◽  
Pulse Wave ◽  
Carotid Sinus ◽  
Relative Timing ◽  
Relative Delay ◽  
Activation Times

Changes in pulse-wave velocity were simulated by changing the relative timing between aortic and carotid sinus barorecptor activity in anesthetized rabbits and dogs. In the rabbit, electrical stimulation was used to vary the timing; in the dog, it was also varied by perfusing the carotid sinuses with externally generated pressure pulses that could be triggered in any portion of the cardiac cycle. Changing the relative delay between aortic and carotid sinsus nerve stimulation did not result in variations of blood pressure or heart rate in the rabbit. Varing the time of electrical stimulation of the carotid sinus nerve caused at most 5 mmHg change of blood pressure in the dog. Delay-related heart-rate changes could be usually observed only when the stimulus consisted of short, high-intensity bursts. When the carotid sinus was externally perfused with pulses of pressure, only one out of five dogs showed delay-related variations in blood pressure (3mmHg) and heart rate (6 beats/min). It is concluded that variations in pulse-wave velocity are unlikely to play a significant role in acute cardiovascular control.

Autonomic mechanisms underlying area postrema stimulation-induced cardiovascular responses in rats

1991 ◽  
Vol 261 (1) ◽  
pp. R1-R8 ◽  
Author(s):  
A. V. Ferguson ◽  
P. Smith
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Rate Control ◽  
Area Postrema ◽  
Cardiovascular Responses ◽  
Pressure Control ◽  
Blocking Agent ◽  
Adrenergic Blockade ◽  
Neural Pathways ◽  
Heart Rate Control

Experiments were designed to examine the autonomic mechanisms underlying the decreases in blood pressure and heart rate elicited by electrical stimulation in the rat area postrema (AP). Vagotomy was found to significantly reduce the bradycardia observed in response to AP stimulation (control -123.5 +/- 23.5 beats/min; vagotomized -7 +/- 5.4 beats/min; P less than 0.001) but was without significant effect on blood pressure responses. Hexamethonium significantly reduced both heart rate (control -225.5 +/- 11.9 beats/min; hexamethonium -5.5 +/- 2.8 beats/min; P less than 0.001) and depressor (control -35.4 +/- 4.7 mmHg; hexamethonium -6.4 +/- 0.8 mmHg; P less than 0.001) responses to such stimulation, whereas combined alpha- and beta-adrenergic blockade was without effect. The muscarinic blocking agent atropine also abolished both blood pressure (control -22.0 +/- 4.3 mmHg; atropine 2.8 +/- 4.4 mmHg; P less than 0.01) and heart rate (control -187.0 +/- 41.9 beats/min; atropine 8.8 +/- 2.6 beats/min; P less than 0.01) responses to AP stimulation. These data suggest that AP stimulation influences two separate neural pathways eliciting distinct cardiovascular responses. It would appear that activation of one of these pathways results in activation of vagal efferents to the heart and thus bradycardia. A second parallel pathway influenced by AP stimulation apparently elicits depressor response through actions on cholinergic muscarinic receptors.

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