Involvement of Pro-Apoptotic and Pro-Autophagic Proteins in Granulosa Cell Death

Abstract

Follicular atresia is a process present in all mammals studied. It involves the oocyte and granulosa cells. The apoptotic cell death has been implicated in follicular atresia. Now it is known that the autophagy is a programmed cell death. In this work, atretic follicles of Wistar rats’ ovaries were analyzed, to evaluate the routes of granulosa cell death during the follicular atresia. The apoptosis and autophagy presence was studied by means of ultrastructural and immunohis-tochemical techniques, and by molecular procedures. During atresia, follicular cells undergo the standard processes of cell death, apoptosis and autophagy, as well as a process in which features of both occur in the same cell. Other processes of cell death affect only granulosa cells and involve such features as contraction of cell volume, an increase of the lumen of the nuclear envelope and the endoplasmic reticulum, and loss of contacts with the oocyte, which is also altered.