Expession of Mullerian Inhibiting Substance in the Human Ovary

Kim, Jang Heub; Kim, Mee Ran; Kwon, Dong Jin; Kim, Jin Hong; Rha, Jong Gu; Kim, Soo Pyung; Kim, Kyoung Mee; Kang, Chang Suk

Abstract

Mullerian inhibiting substance(MIS) has been known as a non-steroidal testicular Sertolicell product responsible for the regression of Mullerian duct in male embryos. More recently MIS was also found to be present in an bioactive form in the bovine and rat ovaries but the function of MIS in the ovary has not been fully delineated. In this study, in order to understand its function in the ovary the ontogeny of the production profile of MIS and the pattern of its localization in ovaries from adult normal cycling women were studied by immunohistochemical staining using the rabbit polyclonal antibody against human recombinant MIS that almost completely blocks its biological activity. MIS was detected specifically and exclusively in the cytoplasm of granulosa cells. The flattened granulosa cells in primordial follicles failed to stain for MIS, but the cuboidal cells of growing follicles stained intensely. The granulosa cells of both single and multiple layered growing follicles showed strong specific staining for MIS. Within the multiple layers of granulosa cells, closer to the oocyte, stained more intensely than those near the basement membrane. Similarly, in antral follicles, cumulus cells and periantral granulosa cells stained more intensely than those in the periphery. MIS staining waned in the mature follicles just before ovulation and could not be found in atretic follicles, corpus albicans. In conclusion, this specific localization suggest that MIS may act as an intraovarian regulator of follicular development and oocyte maturation during the adult reproductive cycle.