APOPTOSIS IN GRANULOSA-CELLS INDUCED BY INTRAFOLLICULAR PEPTIDE

Ovarian follicular fluid peptide (OFFP) purified from sheep ovaries ha s been earlier shown to induce degeneration of ovarian follicles in mi ce. In the present study, whether the effect of OFFP on granulosa cell s was similar to apoptosis was studied using three parameters. Immatur e mice injected with pregnant mare serum gonadotropin on day 0 were ad ministered with 10 or 20 mu g of OFFP on day 1 and autopsied on day 2. The granulosa cells were collected from the ovarian follicles. The pr esence of apoptotic bodies were observed by staining the cells with ac ridine orange. DNA profiles of DAPI-stained cells analysed by flow cyt ometry also revealed apoptotic response to OFFP. Furthermore, agarose gel electrophoresis of low molecular weight DNA fraction extracted fro m the cells of OFFP-treated animals confirmed ladder formation and ind uction of apoptosis and not necrosis in granulosa cells. In conclusion , all the three parameters indicated apoptotic changes in granulosa ce lls of ovarian follicles in mice treated with OFFP. The effect of OFFP seems to be exerted directly on the granulosa cells showing its autoc rine role in the process of follicular atresia. This is discussed in t he light of other intra/extra ovarian factors.