Effects of photoperiod, temperature and testosterone-treatment on plasma T3 and T4 levels in the Djungarian hamster,Phodopus sungorus
- 13 Downloads
The effects of photoperiod, temperature and testosterone treatment on plasma T3 and T4 levels were investigated in the Djungarian hamster. Plasma T3 level was affected by temperature (25°C<7°C) but not by photoperiod. Plasma T4 level was affected by photoperiod (short day < long day) at 25°C. Administration of testosterone increased plasma T4 level under short photoperiod at 25°C. Thus, higher plasma T4 level under long photoperiod at 25°C might be induced by testosterone.
Key wordsDjungarian hamster photoperiod temperature T3 T4 testosterone
- 3.Heldmaier, G., and Steinlechner, S., J. comp. Physiol. (B)142 (1981) 429.Google Scholar
- 4.Wade, G. W., and Bartness, T. J., Am. J. Physiol.246 (1984) R 26.Google Scholar
- 7.Masuda, A., and Oishi, T., J. exp. Zool., in press.Google Scholar
- 12.Vaughan, M. K., Brainard, G. C., and Reiter, R. J., Int. J. Biometeor.28 (1984) 201.Google Scholar