THE HISTOCHEMISTRY OF GLUCOSE-6-PHOSPHATASE IN THE EPIDIDYMIS OF THE MOUSE

Abstract

The distribution and properties of an enzyme hydrolyzing ghucose-6-phosphate have been studied by cytochemical and quantitative methods in the epididymis of the mouse. The enzyme hydrolyzed all hexose-6-phosphate esters at comparable rates and showed lower activity against α-glycerophosphate and fructose-1-phosphate. It also hydrolyzed ribose-5-phosphate. Both cytochemical and quantitative determinations suggested optimal activity at pH 5.5. The enzyme could be distinguished from acid phosphatase on the basis of a different pH optimum, on the basis of its insensitivity to d-tartaric acid, and by its tissue and cellular distribution. The enzyme hydrolyzing ghucose-6-phosphate was distributed homogeneously within the cytoplasm of reactive cells as contrasted to a localization associated with the Golgi region for acid phosphatase. Acid phosphatase was totally inhibited by 0.002 M d-tartaric acid while this concentration had no effect upon activity against ghucose-6-phosphate. It was concluded that the enzyme studied was similar to the glucose-6-phosphatase present in other tissues.