Studies on the control of steroid hormore receptor expression in chicken ovary

点击翻译按钮获取中文摘要

1. Sex steroid hormones are involved in the control of ovarian functions. Our goal was to determine the mechanism of steroid hormone receptor induction in hen ovary.2. Receptors of progesterone, androgen and estrogen (PR,AR and ER) were localized in the ovary by immunocytochemistry and weatern blot analysis. Granulosa cells were positive for AR and ER in growing follicles, whereas positive for AR and PR in follicles just before ovulation. Thecal fibroblasts were positive for AR and PR in all follicles, and estrogen producing cells were positive for ER in growing follicles but not in follicle just before ovulation. These results support current reports suggesting that estrogen and progesterone play important roles for follicular growth and ovulation, respectively.3. Mechanism of PR induction in granulosa cells were examined. Luteinizing hormone (LH) and cAMP were effective to increase the granulosa cell PR in both in vivo and in vitro experiment. The results suggest that LH induces granulosa cell PR through protein kinase A pathway.4. The role of oocyte in follicular maturation was examined. The results suggested that oocyte may play a role to regulate the steroid hormone receptor in follicles becase destruction of oocyte suppressed the preovulatory increase of LH and progesterone. Also, the method of in situ hybridization for PR to detect PRmRNA expression was established.