• Title/Summary/Keyword: Heart rate physiology

Search Result 207, Processing Time 0.022 seconds

Effects of Increasing the Venous Return on the Heart Rate in the Water Turtle - Myogenic Regulatory Mechanisms in the so-called Bainbridge Reflex - (자라에 있어서 정맥환류량(靜脈還流量)의 증가(增加)가 심박(心博)에 미치는 영향(影響))

  • Yang, Woo-Jin;Lee, Jong-Eun;Gill, Won-Sik
    • The Korean Journal of Physiology
    • /
    • v.11 no.2
    • /
    • pp.17-22
    • /
    • 1977
  • By the intravenous infusion of saline solution through the postcaval vein, the effects of increasing the venous return on the heart rate were studied in the water turtle (Amyda japonica). The following results were obtained: 1) Prior to saline infusion, when the initial heart rate was below $50{\sim}55/min$ the heart rate was increased by the infusion. When the initial rate was above this value no changes in heart rate were observed following the infusion. 2) When the heart rate was decreased by vagal stimulation, the infusion elicited a remarkable increase in the heart rate. 3) Increased heart rate caused by tile infusion was not affected by vagotomy or sympathectomy. 4) These results suggest that the increase in heart rate secondary to increased venous return is under the control of a myogenic regulatory mechanism, not a neural mechanism.

  • PDF

Studies on the Diving Bradycardia in the Athletes (운동선수에 있어서 잠수서맥에 관한 연구)

  • Park, Hae-Kun;Lim, Hyen-Jae;Lee, Kyung-Youl;Park, Chan-Hee;Kim, Jong-Chul
    • The Korean Journal of Physiology
    • /
    • v.14 no.1
    • /
    • pp.15-23
    • /
    • 1980
  • In an attempt to clarify the influence of lung volume and water temperature on the heart rate response during apneic face immersion in the trained athletes, 10 soccer players were studied while holding their breath as long as possible after full inspiration(TLC), full expiration(RV) or normal breath(FRC) with face immersion in water. The electrocardiogram(Lead II) was recorded before and during each manuever and compared with 20 control subjects. The results are summarized as follows; 1) Resting heart rate was significantly lower in the athletes than that of the control groups. 2) During apneic face immersion, severe bradycardia were observed in both groups and the heart rate was significantly lower in the athletes than that of the control groups. 3) The degree of the bradycardia (maximum percent reduction of heart rate, HRmax.) were inversely propotional to the lung volume and water temperature. In the above results, bradycardial response was more sensitive in the athletes than the control. It was suggested that diving bradycardia was related to the gas content in the lung and reflex from the cold receptor in the face.

  • PDF

Acceleratory Action of Ginseng Glycosides on the Recovery Heart Rate after Strenuous Exercise in Men and Women (격심한 운동후 심장박동수에 미치는 인삼 총배당체의 회복 촉진작용)

  • Lee, Jae-Kon;Nam, Kee-Yong
    • The Korean Journal of Physiology
    • /
    • v.8 no.2
    • /
    • pp.79-90
    • /
    • 1974
  • In 24 men and 12 women recovery of heart rate after strenuous exercise was observed before and after administration of total ginseng glycosides. In men 100 mg of ginseng glycosides were given twice with a 3 hour interval on the day of treadmill test and in women two more administrations of ginseng glycosides were added on the day before the exercise test. The action of ginseng glycosides was interpreted as an adaptogen, i.e., to enhance the recovery to the physiological equilibrium from the displace4 state. Recovery of heart rate to the pre-exercise state was observed for 20 minutes after strenuous exercise of 2 minutes duration on a treadmill (8 km/hr, 15% grade). In men the recovery of heart rate was enhanced$(P<.2{\sim}.4)$ after ginseng glycosides administration. In women the acceleration of recovery heart rate was highly significant $(P<.01{\sim}.05)$ after ginseng glycosides administration. In men and women recovery heart rate at 3 minute of recovery period after ginseng glycosides equaled to the value at 6 minute of recovery period before ginseng administration.

  • PDF

Effects of Potassium Ion Concentrations on the Cardiac Performances in the Turtle Heart Amyda japonica (자라 심장 박출량과 $K^{+}$ 농도)

  • Kim, Jun;Nam, Kee-Yong
    • The Korean Journal of Physiology
    • /
    • v.14 no.1
    • /
    • pp.31-39
    • /
    • 1980
  • Changes in cardiac performances were observed under variations of the arterial and/or venous pressures with K-loading or K-depletion in turtle heart. Hearts were perfused with turtle Ringer-Locke's solutions containing various levels of potassium ion concentration. When venous pressure increased from 4 to 12 cm $H_2O$, cardiac output increased from $6.2{\pm}0.68$ to $15.7{\pm}0.75\;ml/min$, concomittantly. On the contrary, cardiac output decreased during the elevation of arterial pressure. Stroke work increased more prominently during the arterial pressure elevation than during the elevation of venous pressure. During K-depletion$(1{\sim}2mEq/L)$, cardiac output increased to two times that of normal K-concentration$(3{\sim}6\;mEq/L)$ group. Heart rate increased also, but less markedly. In K-loaded$(7{\sim}8\;mEq/L)$ group, both the cardiac output and heart rate decreased but stroke volume rather increased, because heart rate decrement was disproportionate to that of cardiac output. We concluded that in perfused turtle heart, cardiac output variation was more sensitive to K_depletion whereas heart rate to K-loading.

  • PDF

Physiological analysis of mountain climbing exercise (등산운동의 생리학적 분석)

  • Kim, Wan-Tai;Nam, Kee-Yong
    • The Korean Journal of Physiology
    • /
    • v.5 no.2
    • /
    • pp.15-27
    • /
    • 1971
  • Physiological analysis of the physical exercise was made on 9 subjects performing mountain climbing. The course between two points (256 and 516 meters altitude) was 1,300 meters in distance and difference of vertical height was 260 meters making the mean grade of 20%. In the field, the heart rates during uphill or downhill walk were recorded by EKG radio-telemetry. In the laboratory, oxygen consumption was obtained by the recorded heart rates, using individual heart rate vs oxygen consumption diagram obtained by treadmill test. the following results were obtained. 1. Uphill walk time was 36.5 minutes, and during this period the mean heart rate was 149.0 heats/min and peak heart rate was 169.2 beats/min. The total heart beats during the uphill walk was 5.433 beats. 2. The ratio of individual mean heart rate during the uphill walk to the maximal heart rate distributed between 66.6% and 98.3%, and the mean of the total group was 83.1%. The ratio of peak heart rate of uphill walk to the maximal heart rate was 94.5% in the group. Thus uphill walk of a 20% grade mountain course was an exhaustive exercise. 3. Oxygen consumption during uphill walk was 2.22 l/min (ranged between 1.79 and 2.70 l/min) and the ratio of this to the resting oxygen consumption was 8.31. The peak value of oxygen consumption during uphill walk was 2.73 l/min and the ratio of this to the resting oxygen consumption was 10.39. 4. Energy expenditure during uphill walk showed a mean of 11.1 kcal/min and the peak expenditure rate was 13.6 kcal/min. The total energy expenditure during 36.5 minutes of uphill walk was 396 kcal. 5. In downhill walk, the time was 31.7 minutes, mean heart rate was 118.4 (ranged between 100.1 and 142.7) beats/min, and the peak heart rate was only 129.4 beats/min. The ratio of mean heart rate to the maximal heart rate was 66.3%. Total heart beats during downhill walk was 3,710 beats. The ratio of downhill oxygen consumption to the resting consumption was 5.70. The rate of energy expenditure was 7.5 kcal/min, and the total onery expenditure during the 31.7 minutes of downhill walk was 228 kcal. 6. The effect of training was manifest in the uphill walk and not in the downhill walk. After training in mountain course walk, i) the uphill time was shortened, ii) mean heart rate increased, iii) time vs heart rate curve became smooth and showed less frequent zig-zag, i.e., the depth of trough on the curve decreased and the magnitude was less than 10 beats. In non-trained subject the depth of trough on the curve was greater than 50 beats and appeared more frequently. 7. Mountain climbing is a good health promotion exercise. For the promotion of health the reasonable amount of uphill mountain walk exercise in a 20% grade course is a walk for 40 or 50 minutes duration once a week.

  • PDF

Changes of the Electrocardiogram and Blood Picture of Frogs in Four Seasons (개구리 심전도(EKG) 및 혈액상의 계절에 따른 변화)

  • Rhee, Jung-Moo;Bae, Sung-Ho;Shin, Hyun-Chan;Chae, E-Up
    • The Korean Journal of Physiology
    • /
    • v.8 no.2
    • /
    • pp.33-44
    • /
    • 1974
  • The electrocardiogram of frogs were obtained in winter (January), spring (April), summer (July) and autumn (September and November). Electrocardiograms were recorded applying electrodes to the atria, ventricle and apex of the heart by unipolar or bipolar leads. V wave was recorded prior to P wave, for the presence of the sinus venosus which controls the automaticity of the frog heart, in four seasons. Regardless of the leads or the position of the electrodes P wave was diphasic and wide. According to the rise of temperature the rate of heart beat was increased, and V-P and P-R interval were shortened. Two regression line between R-R interval and both V-P interval and P-R interval were drawn. These were calculated as V-P interval=1 0.276R-R $interva1+0.067{\pm}0.15$ (sec.) and P-R interval=0.179R-R $interva1+0.155{\pm}0.1$ (sec). From these calculation the larger gradient of V-P interval than P-R interval was suggestive that the heart rate is more dependent on the changes of V-P interval than that of P-R interval. Changes of the heart rate were also measured in four seasons and artificial temperatures. Two regression lines between the heart rate (H.H.) and both seasonal temperature (T) and artificial temperature, were drawn. These two lines were calculated as H.R.=20+3.71 (T-10) and H.R.=32+1.425 T respectively. From two gradients of the above equations it is considered that the changes of the heart rate in artificial temperature were milder than that in seasonal temperature. The number of RBC and WBC of frogs were measured in four seasons and a tendency of the changes was observed according to the seasonal variation.

  • PDF

Study on Effects of Incense Smokes Composed with Oriental Medical Herbs on HRV and Stress Relaxation (한약재 훈법(熏法)의 심박변이도 및 스트레스 이완에 미치는 임상 효과)

  • Hwang, Chi-Hyuk;Kim, Kyoung-Shin;Uhm, Ji-Tae;Hwang, Seock-Yeon;Jo, Hyun-Kyung;Kim, Byoung-Soo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.26 no.4
    • /
    • pp.566-571
    • /
    • 2012
  • The purpose of this study was to assess the effects of herbs aroma on relaxation in highly stressed volunteers with heart rate variability(HRV) and SACL(stress arousal check list). 28 highly stressed volunteers participated in this study. The volunteers were examined with heart rate variability(HRV) and SACL(stress arousal check list) before and after smell herbs aroma. After smelling powder incense composed with oriental medicine herbs, mean RR, SDNN, LF, HF, TP were incresed and mean HRV, LF/HF ratio were decreased, but it was not significant. And VLF, norm HF were incresed and norm LF was decreased significantly. This results show that the powder incense composed with oriental medicine herbs effects on decresing sympathetic nervous activity and increasing parasympathetic activity and rebalancing autonomic nervous system who were under stress.

Teucrium polium L. Improved Heart Function and Inhibited Myocardial Apoptosis in Isolated Rat Heart Following Ischemia-Reperfusion Injury

  • Mahmoudabady, Maryam;Talebian, Faezeh Sadat;Zabihi, Narges Amel;Rezaee, Seyed Abdolrahim;Niazmand, Saeed
    • Journal of Pharmacopuncture
    • /
    • v.21 no.3
    • /
    • pp.159-167
    • /
    • 2018
  • Objectives: Myocardial reperfusion is the only logical cure for ischemic heart disease. However, ischemic-reperfusion (I/R) injury is one of the underlying factors facilitating and accelerating the apoptosis in the myocardium. This study set to investigate the impact of Teucrium polium (TP) hydro-alcoholic extract on I/R induced apoptosis in the isolated rat heart. Methods: Isolated rat hearts were classified into six groups. The control samples were subjected to 80 min of perfusion with Krebs-Henseleit bicarbonate (KHB) buffer; in control-ischemia group, after primary perfusion (20 min) the hearts were exposed to global ischemia (20 min) and reperfusion (40 min). Pretreated groups were perfused with $500{\mu}M$ of vitamin C and various TP concentrations (0.5, 1, 2 mg/ml) for 20 min, and then the hearts were exposed to ischemia and reperfusion for 20 min and 40 min, respectively. Cardiodynamic parameters including rate pressure product (RPP), heart rate (HR), the maximum up/down rate of left ventricular pressure (${\pm}dp/dt$), left ventricular developed pressure (LVDP), and coronary artery flow (CF) were achieved from Lab Chart software data. The Bax and BCl-2 gene expressions were measured in heart samples. Results: Hearts treated with TP extract and vit C represented a meaningful improvement in cardiac contractile function and CF. The overexpression of Bcl-2, downregulation of Bax, and improvement of apoptotic index (Bax/Bcl-2) were observed in pretreated TP extract and vit C hearts. Conclusion: The TP extract was found to ameliorate the cardiac function in the reperfused myocardium. Also, it can hinder apoptotic pathways causing cardioprotection.

Effect of Intrahypothalamically Injected Tetrodotoxin on Pressor Responses to Electrical Stimulation in tao Hypothalamus (시상하부내로 투여한 Tetrodotoxin이 혈압 및 시상하부의 전기자극에 의한 승압반응에 미치는 영향)

  • Kim, Jong-Shik;Shin, Hong-Kee;Kim, Kee-Soon
    • The Korean Journal of Physiology
    • /
    • v.11 no.2
    • /
    • pp.23-31
    • /
    • 1977
  • It is Proposed in the Present study to investigate the effects of TTX intravenously or intrahypothalamically administered on the arterial blood pressure and respiration and also to explorc effect of intrahypothalamically administered TTX on the pressor responses to electrical stimulation in the hypothalamus. The results obtained are as follows; 1) The pressor responses to electrical stimulation in the hypothalamus were markedly reduced after administration of TTX. In the $0.01\;{\mu}g/kg$ of TTX administered group, the pressor responses were almost abolished in 6 minutes and there was no tendency toward recovery throughout the experiment. 2) In $0.01\;{\mu}g/kg$ of TTX administered group, the mean arterial blood pressure and heart rate-were gradually reduced while there was a transient increase in respiratory rate followed by slow recovery thereafter. On the other hand no changes in arterial blood pressure, heart rate an4 respiration were observed in $0.005\;{\mu}g/kg$ TTX administered group. 3) Following intravenous administration of $1\;{\mu}g/kg$ TTX, the arterial blood pressure and heart rate were slowly reduced by 60 minutes while no marked changes were found in respiration. From the results of present study it is strongly suggested that TTX exerts its depressant effect not only on peripheral nerves but also on central nervous system.

  • PDF

A Central Pressor Response to Endogenous Nitric Oxide Synthesis Inhibition in Anesthetized Rats

  • Moon, Sung-Ho;Yang, Min-Joon;Oh, Seung-Ho;Kim, Mi-Won;Yoo, Kwang-Jay;Lee, Jong-Eun;Jun, Jae-Yeoul;Yeum, Cheol-Ho;Yoon, Pyung-Jin
    • The Korean Journal of Physiology
    • /
    • v.28 no.2
    • /
    • pp.197-202
    • /
    • 1994
  • The present study was aimed to determine if endogenous L-arginine-nitric oxide (NO) pathway has central, rather than peripheral, mechanisms in blood pressure regulation. Arterial blood pressure and heart rate responses to acute inhibition of the t-arginine-NO pathway were examined in rats anesthetized with thiopental (50 mg/kg, IP). An intracerebroventricular (ICV) cannula was placed in the left lateral ventricle. The right femoral artery was cannulated to measure arterial blood pressure and the vein to serve as an infusion route. $N^G-nitro-L-arginine$ methyl ester (L-NAME) was infused either intracerebroventricularly or intravenously. ICV infusion $(1.25\;{\mu}L/min)$ of L-NAME $(20\;or\;100\;{\mu}g/kg)$ per minute for 60 min) increased the mean arterial pressure and heart rate. Plasma renin concentrations(PRC) were significantly lower in L-NAME-infused group than in the control. L-Arginine $(60\;{\mu}g/min,\;ICV)$ prevented the pressor response to ICV L-NAME. The pressor response was not affected by simultaneous intravenous infusion of saralasin, but was abolished by hexamethonium treatment. Intravenous infusion $(40\;{\mu}L/min,\;10{\sim}100\;{\mu}g/kg\;per\;minute\;for\;60\;min)$ also increased blood pressure, while it decreased heart rate. These results indicate that endogenous L-arginine-NO pathway has separate central and peripheral mechanisms in regulating the cardiovascular function. The central effect may not be mediated via activation of renin-angiotensin system, but via, at least in part, activation of the sympathetic outflow.

  • PDF