EFFECTS OF BLOOD-VOLUME DISTRIBUTION ON THE CHARACTERISTICS OF THE CAROTID BAROREFLEX IN HUMANS AT REST AND DURING EXERCISE

被引:17
作者
EIKEN, O [1 ]
SUN, JCL [1 ]
MEKJAVIC, IB [1 ]
机构
[1] SIMON FRASER UNIV, SCH KINESIOL, BURNABY V5A 1S6, BC, CANADA
来源
ACTA PHYSIOLOGICA SCANDINAVICA | 1994年 / 150卷 / 01期
关键词
ARTERIAL BAROREFLEX; BARORECEPTOR INTERACTION; EXERCISE; PRESSURE-RESPONSE RELATION;
D O I
10.1111/j.1748-1716.1994.tb09663.x
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
Seven supine subjects were studied at rest and during mild to moderate dynamic leg exercise with and without unloading of the cardiopulmonary baroreceptors accomplished by exposing the lower portion of the body to a subatmospheric pressure of 20 mmHg (Lower Body Negative Pressure, LBNP). The function of the cardiac branch of the carotid baroreflex was studied over its full operational range by measuring R-R intervals during application of pulse synchronous graded pressures (40 to -65 mmHg) in a neck-chamber device. Raising the carotid transmural pressure (systolic arterial pressure minus neck-chamber pressure) induced increasing R-R intervals in all conditions. In conformity with previous results from our laboratories it was found that the maximal rate of change in relative R-R intervals and the corresponding transmural pressure were higher during exercise than at rest, indicating that exercise increased the carotid baroreflex sensitivity and shifted its optimal buffering range to higher arterial pressures. LBNP did not affect the characteristics of the reflex at rest nor during exercise. It is concluded that reduced central venous pressure with consequent selective cardiopulmonary receptor disengagement exerts no influence on the carotid baroreflex control of heart rate (HR), as tested over the entire arterial pressure-effector response relation, either at rest or during mild-moderate exercise.
引用
收藏
页码:89 / 94
页数:6
相关论文
共 33 条
[1]   CIRCULATORY EFFECTS OF STIMULATING CAROTID ARTERIAL STRETCH RECEPTORS IN MAN AT REST AND DURING EXERCISE [J].
BEVEGARD, BS ;
SHEPHERD, JT .
JOURNAL OF CLINICAL INVESTIGATION, 1966, 45 (01) :132-&
[2]   THE EFFECT OF BODY POSITION ON THE CIRCULATION AT REST AND DURING EXERCISE, WITH SPECIAL REFERENCE TO THE INFLUENCE ON THE STROKE VOLUME [J].
BEVEGARD, S ;
HOLMGREN, A ;
JONSSON, B .
ACTA PHYSIOLOGICA SCANDINAVICA, 1960, 49 (2-3) :279-298
[3]   BLOOD-PRESSURE AND HEART-RATE REGULATING CAPACITY OF CAROTID-SINUS DURING CHANGES IN BLOOD-VOLUME DISTRIBUTION IN MAN [J].
BEVEGARD, S ;
CASTENFORS, J ;
LINDBLAD, LE ;
TRANESJO, J .
ACTA PHYSIOLOGICA SCANDINAVICA, 1977, 99 (03) :300-312
[4]  
BISHOP VS, 1985, FED PROC, V44, P2377
[5]  
Blomqvist C. G., 1983, HDB PHYSL 2, P1025
[6]   OPERATIONAL SENSITIVITY AND ACUTE RESETTING OF AORTIC BARORECEPTORS IN DOGS [J].
COLERIDGE, HM ;
COLERIDGE, JCG ;
KAUFMAN, MP ;
DANGEL, A .
CIRCULATION RESEARCH, 1981, 48 (05) :676-684
[7]   ONSET OF EXERCISE SHIFTS OPERATING POINT OF ARTERIAL BAROREFLEX TO HIGHER PRESSURES [J].
DICARLO, SE ;
BISHOP, VS .
AMERICAN JOURNAL OF PHYSIOLOGY, 1992, 262 (01) :H303-H307
[8]   BAROREFLEX MODULATION OF SYMPATHETIC ACTIVITY AND SYMPATHETIC NEUROTRANSMITTERS IN HUMANS [J].
ECKBERG, DL ;
REA, RF ;
ANDERSSON, OK ;
HEDNER, T ;
PERNOW, J ;
LUNDBERG, JM ;
WALLIN, BG .
ACTA PHYSIOLOGICA SCANDINAVICA, 1988, 133 (02) :221-231
[9]  
Eckberg DL, 1992, HUMAN BAROREFLEXES H
[10]   CARDIAC RESPONSES TO LOWER BODY NEGATIVE-PRESSURE AND DYNAMIC LEG EXERCISE [J].
EIKEN, O ;
BJURSTEDT, H .
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY, 1985, 54 (05) :451-455