Cytochemical localization of glucose 6-phosphatase activity in membranes of the endoplasmic reticulum and nuclear envelope in mouse hepatocytes.

Abstract

Cytochemical localization of glucose 6-phosphatase activity was studied in membranes of the endoplasmic reticulum and nuclear envelope of mouse hepatocytes. In periportal hepatocytes incubated in the reaction medium for 3min and centrilobular cells incubated for 15mim, the deposition of the reaction product for the activity was little, and therefore, relations between the reaction product and the membranes could be easily observed. In the rough endoplasmic reticulum, the reaction product was generally seen scatteringly on the inner surface of the membrane. In the smooth endoplasmic reticulum, the product appeared generally deposited in the cisternal space. In the nuclear envelope, the product was seen both on the inner surface of the outer nuclear membrane and in the perinuclear cisterna. Thus, the localization pattern of the reaction product was not common among the rough and smooth endoplasmic reticulum, and nuclear envelope. In periportal cells incubated for 5, 10 or 15min, the amount of the reaction product increased. However, the amount of the product was heterogenous in the lateral plane of the endoplasmic reticulum and nuclear envelope.In the rough endoplasmic reticulum, the localization site of G6Pase activity is approximately the inner surface of the membrane.