Endocrinology, Vol 125, 1742-1744, Copyright © 1989 by Endocrine Society

ARTICLES

Cytosolic androgen receptors in the neuroendocrine tissues of the golden hamster: influence of photoperiod and melatonin treatment [published erratum appears in Endocrinology 1990 Feb;126(2):1164]

B Stankov, V Lucini, M Snochowski, B Cozzi, P Fumagalli, G Maccarinelli and F Fraschini
Chair of Chemotherapy, University of Milan, Italy.

Hamsters exposed for eight weeks to short photoperiod (LD 10:14) or treated with melatonin in the late afternoon under long photoperiod (LD 14:10) had significantly higher number of cytosolic androgen receptors in the pituitaries, hypothalami and harderian glands, as compared to the long photoperiod (LD 14:10) exposed controls. The numerical value of the apparent Kd was two to three times lower in the hypothalami and pituitaries, but not in the harderian glands of the animals from these groups. These results indicate that alterations in receptor numbers and affinity constants may be responsible for the dramatic changes in the sensitivity of the hypothalamo-pituitary axis to the negative feedback actions of the gonadal steroids, observed under inhibitory photoperiods and that this effect could be duplicated by late afternoon melatonin treatment.

This article has been cited by other articles:

				E. L. Bittman, D. A. Ehrlich, J. L. Ogdahl, and A. E. Jetton Photoperiod and Testosterone Regulate Androgen Receptor Immunostaining in the Siberian Hamster Brain Biol Reprod, September 1, 2003; 69(3): 876 - 884. [Abstract] [Full Text] [PDF]