|
|
||||||||
Journal of Applied Physiology, Vol 62, Issue 2 646-650, Copyright © 1987 by American Physiological Society
ARTICLES |
L. B. Rowell, G. L. Brengelmann and P. R. Freund
We measured plasma norepinephrine (NE) concentration, an index of sympathetic nervous activity, and epinephrine (E), an index of adrenal medulla activity, in six normal young men during mild to severe exercise, with and without superimposed heat stress. The primary objective was to observe whether the normally close relationship between heart rate and log NE concentration in upset when heart rate at a given work load is increased by heat stress. Exercise, beginning at 50 W, was graded in 50-W increments lasting 10 min each up to 200 W, which lasted 5-10 min. Each subject went through the protocol twice, once with skin temperature kept low by a water-perfused suit and then with skin temperature raised to 38 degrees C. Exogenous heart stress raised log circulating NE concentration in proportion to the rise in heart rate at a given work load so that the usual relationship between these variables, previously observed during other stresses, was preserved. In contrast to some other stresses, heat stress had no added effect on E concentration, indicating that this stress during exercise raises sympathetic neural activity (as reflected in the rise in NE) without stimulating additional adrenal release of E.
This article has been cited by other articles:
![]() |
M. Y. Endo, R. Suzuki, N. Nagahata, N. Hayashi, A. Miura, S. Koga, and Y. Fukuba Differential arterial blood flow response of splanchnic and renal organs during low-intensity cycling exercise in women Am J Physiol Heart Circ Physiol, May 1, 2008; 294(5): H2322 - H2326. [Abstract] [Full Text] [PDF] |
||||
![]() |
X. Bao, C. M. Lu, F. Liu, Y. Gu, N. D. Dalton, B.-Q. Zhu, E. Foster, J. Chen, J. S. Karliner, J. Ross Jr, et al. Epinephrine Is Required for Normal Cardiovascular Responses to Stress in the Phenylethanolamine N-Methyltransferase Knockout Mouse Circulation, August 28, 2007; 116(9): 1024 - 1031. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |