Observations on the origins of plasma membrane in rat deciduoma

An NADH-ferricyanide reductase activity resistant to inactivation by cytochemical procedures was examined during decidualization of rat endometrium. Resistant activity was restricted to plasma membranes, distal elements of the Golgi apparatus, and discoid cisternae and cytoplasmic vesicles of decidual cells of endometrium of the pseudopregnant rat on days 3, 4, 5, 7, and 9, after mating. The procedure reduced or eliminated any evidence of NADH-ferricyanide reductase activity from other cellular components such as endoplasmic reticulum, nuclei, and mitochondria. The observations of the glutaraldehyde-resistant reductase in both plasma membranes and discoid cisternae may indicate a role for the latter in the biosynthesis of plasm membranes during decidualization when massive cell proliferation and membrane biosynthesis occur. The origin of the discoid cisternae is tentatively ascribed to the mature faces of the Golgi apparatus.