RT Journal Article
SR Electronic
T1 Melatonin induction of gonadal quiescence in pinealectomized Syrian hamsters
JF Science
JO Science
FD American Association for the Advancement of Science
SP 953
OP 955
DO 10.1126/science.563102
VO 198
IS 4320
A1 Tamarkin, L
A1 Hollister, CW
A1 Lefebvre, NG
A1 Goldman, BD
YR 1977
UL http://science.sciencemag.org/content/198/4320/953.abstract
AB Pinealectomized Syrian hamsters were injected thrice daily with 25 micrograms of melatonin per injection. The injections were administered at 3-hour intervals either during the day or during the night of a photoperiodic cycle of 14 hours of light and 10 hours of darkness. After 6 weeks of treatment with melatonin during the night, both pinealectomized and intact hamsters had reduced testis weight, and pinealectomized hamsters showed decreased levels of serum gonadotropins. Injection of melatonin during the day for 7 weeks either once (75 micrograms) a day or thrice (25 micrograms per injection) daily caused a reduction in testis weight in pinealectomized hamsters. Both pinealectomized and intact females injected with melatonin thrice daily during the day became anovulatory by week 7 of treatment. These results are similar to those observed when hamsters are exposed to a short photoperiod, suggesting that melatonin may be acting as a hormone in mediating the effects of photoperiod on the reproductive system of the Syrian hamster.