AJP - Regulatory, Integrative and Comparative Physiology, Vol 259, Issue 3 470-R477, Copyright © 1990 by American Physiological Society

ARTICLES

Hypothalamic adrenoceptors mediate sympathoadrenal activity in exercising rats

A. J. Scheurink, A. B. Steffens and R. P. Gaykema
Department of Animal Physiology, State University of Groningen, Haren, The Netherlands.

The role of hypothalamic adrenoceptors in the exercise-induced alterations of plasma norepinephrine (NE), epinephrine (E), and corticosterone concentrations was investigated in rats. Exercise consisted of strenuous swimming against a counter-current for 15 min. Before, during, and after swimming, blood samples were withdrawn through a permanent heart catheter for determination of E, NE, and corticosterone. In control rats E, NE, and corticosterone levels were all increased during exercise. Infusion of the alpha-adrenoceptor antagonist phentolamine through permanent bilateral cannulas into the ventromedial hypothalamus (VMH) immediately before exercise reduced the exercise-induced increase in plasma E without affecting NE. Infusion of the beta-adrenoceptor antagonist timolol into the VMH enhanced plasma E and attenuated plasma NE increases. Infusion of phentolamine into the lateral hypothalamic area (LHA) led to enhanced NE and unchanged E concentrations, whereas infusion of timolol into the LHA caused a potentiation of the increase in plasma E without an effect on NE. Plasma corticosterone concentrations were not affected. The results suggest that 1) alpha- and beta-adrenoceptors in the hypothalamus influence peripheral catecholamine release, and 2) E and NE responses to exercise can be dissociated by interference of the central nervous system.

This article has been cited by other articles:

				T. Shibakusa, W. Mizunoya, Y. Okabe, S. Matsumura, Y. Iwaki, A. Okuno, K. Shibata, K. Inoue, and T. Fushiki Transforming growth factor-beta in the brain is activated by exercise and increases mobilization of fat-related energy substrates in rats Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2007; 292(5): R1851 - R1861. [Abstract] [Full Text] [PDF]

				K. T. Higa-Taniguchi, F. C. P. Silva, H. M. V. Silva, L. C. Michelini, and J. E. Stern Exercise training-induced remodeling of paraventricular nucleus (nor)adrenergic innervation in normotensive and hypertensive rats Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2007; 292(4): R1717 - R1727. [Abstract] [Full Text] [PDF]

				M. G. de Vries, M. A. Lawson, and J. L. Beverly Hypoglycemia-induced noradrenergic activation in the VMH is a result of decreased ambient glucose Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2005; 289(4): R977 - R981. [Abstract] [Full Text] [PDF]

				M. G. de Vries, M. A. Lawson, and J. Lee Beverly Dissociation of hypothalamic noradrenergic activity and sympathoadrenal responses to recurrent hypoglycemia Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2004; 286(5): R910 - R915. [Abstract] [Full Text] [PDF]

				S. B. Evans, C. W. Wilkinson, K. Bentson, P. Gronbeck, A. Zavosh, and D. P. Figlewicz PVN activation is suppressed by repeated hypoglycemia but not antecedent corticosterone in the rat Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2001; 281(5): R1426 - R1436. [Abstract] [Full Text] [PDF]

				J. L. Beverly, M. G. de Vries, M. F. Beverly, and L. M. Arseneau Norepinephrine mediates glucoprivic-induced increase in GABA in the ventromedial hypothalamus of rats Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2000; 279(3): R990 - R996. [Abstract] [Full Text] [PDF]

				K. S. Butcher and D. F. Cechetto Receptors in lateral hypothalamic area involved in insular cortex sympathetic responses Am J Physiol Heart Circ Physiol, August 1, 1998; 275(2): H689 - H696. [Abstract] [Full Text] [PDF]