Srivastava M, Haldar C
Department of Pathology, Banaras Hindu University, Varanasi, India.
Indian J Exp Biol. 1992 Apr;30(4):264-70.
F. pennanti presented a clear biphasic pineal mediated seasonal sexual cycle. This sexual cycle was essentially characterised by a very short period of sexual quiescence with an arrest of spermatogenesis during October-November. A small but clear decrease in sexual activity was also observed during March-April. This decrease in sexual activity, however, had no quantifiable effect on spermatogenesis. Sexual recrudescence was observed from December-January. The testes remained sexually active from January till September. Almost an inverse relationship was observed between pineal and testicular weight. Pinealectomy, however, prevented naturally induced gonadal regression during both the periods, i.e. September-November and February-April. Exposure of animals to high RH (80 +/- 4%) during sexually active phase induced a steep regression in testicular weight of sham-operated animals even in the presence of gonad stimulatory long photoperiod (16L:8D) and high temperature (40 degrees +/- 5 degrees C) while exposure of animals to moderate RH (65 +/- 5%) during sexual regression phase partially prevented testicular regression even in presence of inhibitory short photoperiod (11L:13D) and normal environmental temperature (30 degrees +/- 5 degrees C). Pinealectomized animals, neither exhibited testicular regression in February-March nor had involuted testes in September-October, thus, suggesting that the effect of humidity is mediated via the pineal gland.
彭南特氏伶鼬呈现出明显的由松果体介导的季节性性周期。这个性周期的基本特征是在10月至11月期间有一段非常短暂的性静止期，精子发生停止。在3月至4月期间也观察到性活动有轻微但明显的下降。然而，这种性活动的下降对精子发生没有可量化的影响。从12月至1月观察到性复苏。睾丸从1月到9月一直保持性活跃。松果体重量与睾丸重量之间几乎呈反比关系。然而，松果体切除可防止在9月至11月和2月至4月这两个时期自然诱导的性腺退化。在性活跃期将动物暴露于高相对湿度（80±4%），即使存在性腺刺激的长光照周期（16小时光照：8小时黑暗）和高温（40℃±5℃），假手术动物的睾丸重量也会急剧下降；而在性消退期将动物暴露于中等相对湿度（65±5%），即使存在抑制性的短光照周期（11小时光照：13小时黑暗）和正常环境温度（30℃±5℃），也能部分防止睾丸退化。松果体切除的动物在2月至3月既没有表现出睾丸退化，在9月至10月睾丸也没有萎缩，因此表明湿度的影响是通过松果体介导的。
