| Many rodents are seasonal breeding animals and the onset or termination of their breeding can be influenced by the day length, which changes seasonally. Typically, the size of the gonads and sexual accessory tissues of photoperiod-responsive rodents atrophy and the secretion of gonadal and pituitary hormone decrease when the animals are kept in short photoperiods.6-MBOA, one of plant secondary metabolites (PSM), exists mainly in rapidly growing tissues of some monocotyledonous plants. It was reported that6-MBOA can stimulate the reproduction of some herbivorous mammals and alleviate the inhibitory effects of a shorter photoperiod. In order to study the effects of6-MBOA on the reproduction of Brandt’s voles, to elucidate the mechanism of this effect, verify the hypotheses that6-MBOA can promote animal breeding and provide a theoretical basis for the coevolution between animal and plant, Brandt’s voles, which were bred in laboratory, were injected, intraperitoneally, with different doses of6-MBOA for12days. Then, the changes of the serum contents of hormones related to reproduction were observed by Elisa. In addition, the fluorescence quantitative real-time PCR was used to determine the expressions of hypothalamic genes related to reproduction and the gonadal genes related to the synthesis of sex hormone and method of western blot was used to detecte the contents of synthetase of sex hormone. The results were as follows:1) Long-term injection of different doses of6-MBOA did not influence the body weight of adult males and females. This showed that6-MBOA had no significant effects on the body weight of Brandt’s vole.2) The testicular index and uterine index of low and middle dose group was significantly higher than that of control group (P<0.05). The seminal vesicle storage index in the middle dose group was higher than that of control group (P<0.05). It indicated that6-MBOA promoted the growth of sexual organs of Brandt’s voles.3) LH and T levels in males of low and middle dose group were significantly higher than that in the control group(P<0.05). The level of E2in the low dose group was significantly higher than that in the control group (P<0.05). The E2levels of female voles in low and middle dose group were significantly higher than that in the control group. FSH in the high-dose group was significantly lower than that in the control group P<0.05).The results meant that6-MBOA increased the level of sex hormones in the serum of Brandt’s vole and the level of gonadotropin in male voles.4) In males, the mRNA level of Kiss1in AVPV of hypothalamus and Gnrh in ARC of hypothalamus in the low dose group were significantly higher than that in the control group(P<0.05). While the mRNA level of Kiss1and Gpr54in ARC in the middle and high dose groups were significantly lower than that in the control group(P<0.05). In females, the mRNA level of Kiss1in AVPV of hypothalamus in the low and middle dose groups were significantly higher than that in the control group (P<0.05). Similarly, the mRNA level of Gnrh in the low dose group was significantly higher than that in the control group(P<0.05). While the mRNA level of Gpr54in the middle and high dose group was significantly lower than that in the control group(P<0.05). The results showed that a certain dose of6-MBOA could promote the expressions of Kissl in AVPV of hypothalamus and Gnrh in ARC of hypothalamus.5) In males, the mRNA level of Star and Cypllal in the testes in the low and middle dose group was significantly higher than that in the control group(P<0.05). The contents of StAR in the testes in the low and medium groups were significantly higher than that in the control group (P<0.05) and the content of P450scc in the low group was significantly higher than that in the control group(P<0.05). In females, the mRNA levels of Star, Cyplla1and Cyp19in the ovaries in the low dose group were significantly higher than that in the control group(P<0.05). The contents of StAR in the testes in the low dose group was significantly higher than that in the control group(P<0.05). The contents of P450arom in the ovaries in the low and middle groups were significantly higher than that in the control group(P<0.05). The results showed that a certain dose of6-MBOA could increase the transcription and expression of the genes of synthetase of gonadal sex hormone.In summary,6-MBOA may abate the inhibitory influence of shorter photoperiod on Brandt’s vole and stimulate the reproduction of this animal. Our work verified the hypothesis that6-MBOA can promote the reproduction of Brandt’s voles in short photoperiod. |
PDF Full Text Request