The influence of short photoperiod on testicular and circulating levels of testosterone precursors in the adult golden hamster

Biology of Reproduction
V Chandrashekar, A Bartke

Abstract

The in vivo effects of short photoperiod (SPP, 6L:18D) for 8 and 12 wk on plasma and testicular levels of testosterone (T) precursors in adult golden hamsters were evaluated. Plasma and testicular progesterone (P), 17 alpha-hydroxyprogesterone (17 alpha-OHP), androstenedione (A-dione), and T were measured after 5 injections of saline or human chorionic gonadotropin (hCG) (5 or 25 IU/day). The basal levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL) in circulation were also determined. There were significant reductions in the weight of the testes in animals exposed to SPP. After 12 wk in SPP, circulating levels and testicular content of 17 alpha-OHP, A-dione, and T were significantly reduced, suggesting that the decrease in T secretion may be associated with the impairment of synthesis and/or action of 17 alpha-steroid hydroxylase, C17-20 steroid lyase, and 17 beta-hydroxysteroid dehydrogenase enzymes in the testes. Exposure to SPP for 8 wk resulted in decreased plasma and testicular content of T. Although there were reductions in testicular content of 17 alpha-OHP and A-dione, this was not reflected in plasma levels of these steroids. After 8 and 12 wk of exposure to SPP, hCG treatment i...Continue Reading

Citations

Aug 12, 1999·International Journal of Andrology·M B FrungieriR S Calandra
Dec 15, 1991·Proceedings of the National Academy of Sciences of the United States of America·M Dubois-DauphinJ J Dreifuss
Jan 1, 1991·Journal of Biological Rhythms·M JallageasJ Nouguier-Soulé
Nov 10, 2020·General and Comparative Endocrinology·Lisa N Bottalico, Aalim M Weljie

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