The Effects Of Orexin A On StAR、CYP11和3β-HSD In Luteinized Granulose Cells In Ovine

Orexin is neuropeptides which exert function by its receptor (OX1R and OX2R) mainly. It is diyided into Orexin A and Orexin B. Many studies show that Orexin is distributed widely, and its physiological functions is diverse, including food intaking and energy balance, effects on the endocrine and drug addiction as well as the regulation of reproductive activity and so on.In order to explore the effects of different concentrations of Orexin A in different times on StAR、CYP11and3β-HSD (genes related luteal fuction) in luteinized granulose cells in ovine, first of all, in this study we culture ovarian granulose cells in vitro and transform it into granulose luteal cells,that is to say, culturing cells24h after adding LH(2.5IU/ml), FSH(2.5IU/ml) and E2(1μg/mL). This cells are treated with different concentrations (0.05,0.2,0.5and1μg/mL), total RNA from cells is extracted in0,2,6,12h and24h respectively, and the expression of Bax/Bcl-2, OX1R and luteal marker genes that CYP11,3β-HSD, StAR mRNA by qPCR. The results shows that level of Bax/Bcl-2increased dramatically after treated with Orexin A which compared with the control group, that is to say Orexin A can promote luteinized granulose cells apoptosis;1μg/mL Orexin A in2h and0.2μg/mL in12h can upregulated the expression of OX1R mRNA and promote luteolysis compared with the control group. The expression of StAR、CYP11and3β-HSD mRNA is decreased significantly treated with1u g/mL Orexin A in2h compared with the control, StAR and3β-HSD mRNA has an significant increase treated with0.2μg/mL in12h while CYP11has no notable variation, these results display that1μg/mL and0.2μg/mL Orexin A can inhibit expression of StAR、 CYP11and3β-HSD mRNA in2h and12h respectively, thereby it can promote luteal’s degeneration.In this study, we culture ovarian granulose cells in vitro and transform it into granulose luteal cells, then treat this cell with the different concentrations Orexin A in different times, define the effects of Orexin A on StAR、CYP11and3β-HSD mRNA in luteinized granulose cells in ovine. The paper makes a foundation for function of Orexin A on reproductive.