Immunohistochemical localization of androgen receptor in the human ovary throughout the menstrual cycle in relation to oestrogen and progesterone receptor expression

Abstract
In order to elucidate the role of androgen receptors (AR) in human ovaries, we examined their immunohistochemical localization, in comparison with oestrogen receptors (ER) and progesterone receptors (PR), at various stages of the menstrual cycle and follicular development. Primordial and primary follicles did not express AR. In granulosa and thecal cells of secondary follicles there was weak nuclear staining for AR. Granulosa cells of dominant follicles showed moderate nuclear staining for AR, which was stronger than that in thecal cells. In the luteal phase, the staining intensity for AR was strongest in the early luteal phase just after ovulation and declined gradually thereafter. Thecal cells of atretic follicles showed moderate nuclear staining for AR, which was a little stronger than that in dominant follicles. There was weak nuclear staining for AR in stromal cells surrounding follicles. Though there was variation in the staining intensity, AR were present at almost all stages of the menstrual cycle. There is a possibility that androgens, mediated by AR, may play an essential role in follicular growth and maturation, atresia and luteinization as autocrine or paracrine agents.