The formation and cytochemical characterization of cortical granules in ovarian oocytes of the golden hamster (Mesocricetus auratus).

The formation and cytochemical characterization of cortical granules in the ovarian oocytes of the golden hamster have been investigated by use of light and electron microscopical techniques. Particular emphasis is given to the changing population of organelles associated with cortical granule formation. Our observations indicate that cortical granules are produced by the participation of both the Golgi complex and the rough endoplasmic reticulum. Ultrastructural cytochemistry reveals that the cortical granules are composed of glycoprotein. The cortical granules are released at fertilization by a merocrine-type of secretory process.