Exchange of Cytoplasm Between Cells of the Membrana Granulosa in Rabbit Ovarian Follicles

Abstract

The cells of the membrana granulosa contain numerous spherical inclusions which appear in any portion of their cytoplasmic matrix. These structures are bounded by a 20 nm double membrane, and their diameter ranges from about 0.3–3.0 µm. They form when a cytoplasmic process from one granulosa cell is completely incorporated into an adjoining cell. This transfer of cytoplasm occurs only at zonulae occludentes which develop between adjoining cells. The inside of the spherical structures inconsistently contain either cytoplasmic ground substance, endoplasmic reticulum, lipid droplets, or mitochondria. The role these structures have in follicular activity is not clear.