Effects Of Photoperiods On Behaviors, Reproductive System And The Expression Of AVP In Hypothalamus In Mandarin Voles

Mandarin vole (Lasiopodomys mandarinus) which belongs to the Rodentia, Cricetidae gross enough vole genus, is the small rodent. Mandarin vole spends almost all its life underground, and this long term subterranean life made the reaction of light degenerated a lot. Because of long term subterranean life and special underground environment, some special adaptive evolution appeared in many aspects of the subterranean rodents. Concrete manifestation of the vast majority of subterranean rodents types of photoperiod induction reduced ability for long-term life of undergroundUnderstanding of photoperiod on the mandarin vole behavior, reproductive system, and the expression of AVP in the hypothalamus nuclei, explore the underground rat reproductive behavior and physiology of seasonal change and its relationship with the photoperiod, In this study, control animals in the laboratory photoperiod exposure mode, the mandarin vole breeding 8-10 on behalf of the field directly capture vole and indoor feeding study, Under 12L:12D photoperiod for 4 weeks after each group, respectively, 16L:8D,12L:12D and 8L:16D under the three levels of light for six weeks, Determination of the behavior in the experimental animals between homosexual and heterosexual, include aggressive behavior, defensive behavior, social behavior and nonsocial behavior; male testis, epididymis, and adrenal, as well as the female’s ovaries, uterus and adrenal weight; Finally, using immunohistochemical methods for the determination of the number of mandarin vole hypothalamic SCN, the PVN and 3V AVP positive cells, an analysis of the effects of relatively light cycle behavior of the mandarin vole, reproductive organs and hypothalamic AVP expression. The results are as follows:1. The results show that:1) light cycles had no significant influence on the behavior of wild mandarin vole; 2) Indoor domesticated reduce aggressive behavior between the mandarin vole with unfamiliar opposite sex, but is not sensitive to photoperiod; 3) Indoor domestication can significantly improve the defensive behavior of female brown hair color voles, but no significant effect on the defense behavior of males; 4) Photoperiod and indoor domesticated vole social behavior and non-social behavior differences were not significant.2. The results show that:1) light cycles had no significant influences on the organ index of wild and domesticated mandarin vole; 2) After long term indoor domestication, the weight of adrenal, ovarian and epididymis were dramatically reduced in mandarin vole; 3) Indoor domestication had no influences on uterine and testicular in mandarin vole.3. The differences of AVP expression in hypothalamus nuclear group SCN, PVN and 3 V area in indoor domesticated mandarin vole under different light cycles. The results show that:1) the number of AVP positive cells in hypothalamus SCN, PVN, and 3V area of female mandarin vole was the most in the condition of long light LD, and the number of positive cells in SCN and 3 V area was significantly more than that in PVN area.2) The number of AVP positive cells in hypothalamus SCN,3V area of male mandarin vole was the most with normal light MD, and light cycles had a significant influence on the number of AVP positive cells in SCN area.