The distribution and fate of 3H-glucose and 3H-galactose in oocytes of Oryzias latipes: Formation of the cortical alevoli.

The distribution and fate of 3H-glucose and 3H-galactose and the formation of the cortical alveoli in the oocytes of the teleost Oryzias latipes were investigated. Fish were given intraperitoneal injections of either labeled hexose, and the relative amounts of each were measured in autoradiographs prepared for light and electron microscopy. There were significant differences in the amounts of each hexose in the oocytes at all time intervals studied. During the earlier time periods, the oocyte incorporates more 3H-glucose than 3H-galactose in both the cytoplasmic and cortical alveoli compartments; however, the overall rate of formation of the cortical alevoli appears to be similar for the two tracers. Electron microscopic autoradiographs reveal the participation of cytoplasmic elements, e.g., endoplasmic reticulum and Golgi apparatus, in the formation of the cortical alveoli. The chorion does not incorporate significant amounts of either tracer, while the yolk granules contain small but significant amounts.