Subcellular distribution of some specific enzymatic activities in human leucocytes

Abstract

The activities and subcellular distribution of the following enzymes: NADH oxidase, alkaline phosphatase, beta-glucuronidase and ATPase, were assayed in human mononuclear and polymorphonuclear leucocytes and in particular the contamination and integrity of the mitochondrial fractions were evaluated with this new separation procedure. Results show that maximal contamination was found to be that from lysosomal beta-glucuronidase especially in polymorphonuclear leucocyte mitochondria fractions. Furthermore oligomycin-sensitive ATPase data suggest that mitochondria do not decrease in number or lose their integrity to a great extent. Controversial p-nitrophenyl-phosphatase activity was also found to be present in polymorphonuclear and mononuclear leucocytes granular-soluble fractions.