Studies of frog oviducal jelly secretion. II. Cytology of secretory cycle This work was supported in part by a grant from the University of Michigan Cancer Research Institute and a training grant from the National Institutes of Health (USPHS Grant no. GM989). Part of a dissertation submitted at the University of Michigan in partial fulfillment of the requirements for the degree of Doctor of Philosophy.

Abstract

Electron microscopy reveals that the secretory glandular cells of the oviduct of Rana pipiens contain granules which may develop from small vesicles with smooth membranes. The latter may represent dispersed Golgi elements, although cytochemical reactions fail to reveal a localized Golgi complex within these cells. Individual granules enlarge throughout the growing season without fusing with other granules. The mature cell is packed with granules, each of which possesses uniquely an interior electron-dense (dense) part and an electron-lucid shell enclosed by a smooth membrane. The dense part first appears as a condensed body. As growth proceeds, the dense component branches to form a net-like pattern within the granule. When the granule has attained its mature size, the dense component appears to revert to a condensed pattern again. Cytoplasmic granules which are observable by light microscopy after staining with toluidine blue at pH 4.0 apparently correspond to the dense component seen in the electron microscope.