Related Experiment Video
Updated: May 21, 2026
07:33
Noninvasive, High-throughput Determination of Sleep Duration in Rodents
Published on: April 18, 2018
Daily melatonin injections inhibit short-day-induced testicular regression in hamsters
Experientia
|December 15, 1980
Abstract:
Daily injections of melatonin were found to retard testicular regression in hamsters exposed to LD 10:14, if the injections occurred in the morning (i.e., 0.5 h after lights on), but not if they occurred in the afternoon (i.e., 6 h after lights on). These results indicate that appropriately times injections of melatonin can at least partially block the inhibitory effects of short days on gonadal activity in the photoperiodic hamster.
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