AJP - Regulatory, Integrative and Comparative Physiology, Vol 269, Issue 1 179-R185, Copyright © 1995 by American Physiological Society

ARTICLES

Voluntary exercise increases gonadotropin secretion in male Golden hamsters

D. R. Pieper, H. Y. Ali, L. L. Benson, M. D. Shows, C. A. Lobocki and M. G. Subramanian
Department of Physiology, Providence Hospital, Southfield 48037, USA.

To determine the effect of voluntary exercise and food restriction on reproductive hormone secretion, 48 adult male hamsters were placed in cages with (EX) or without (SED) running wheels. One-half of the animals in each exercise group was fed ad libitum, and the other half was food restricted to reduce their body weight to 90 g over 4 wk. After 10 wk, the EX ad libitum-fed group had much larger testes and much higher serum follicle-stimulating hormone and testosterone levels than the other three groups, but these values in the EX food-restricted hamsters were similar to those in the SED food-restricted group. In experiment 2, 20 adult male hamsters were castrated and later implanted with silicone rubber capsules containing testosterone. Two weeks after implantation of the capsules, the serum follicle-stimulating hormone levels were higher in the EX than in the SED group of testosterone-treated hamsters, but not in animals receiving blank capsules. These data suggest that exercise increases gonadotropin secretion by inhibiting the negative feedback of testosterone.

This article has been cited by other articles:

				D. R. Pieper and C. A. Lobocki Characterization of Serum Dehydroepiandrosterone Secretion in Golden Hamsters Experimental Biology and Medicine, September 1, 2000; 224(4): 278 - 284. [Abstract] [Full Text]

				H. A. El-Bakry, W. M. Zahran, and T. J. Bartness Photoperiodic responses of four wild-trapped desert rodent species Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1998; 275(6): R2012 - R2022. [Abstract] [Full Text] [PDF]