[Level of endogenous thiol proteinase inhibitors in subcellular fractions of rat hepatocytes]. 
A procedure for isolation of inhibitors of thiol-dependent proteinases was developed as well as distribution of the inhibitors in rat hepatocyte subcellular fractions was studied.  The procedure involved separation of subcellular fractions by means of differential centrifugation, isolation of acid-thermostable proteins and their following purification using affinity chromatography on immobilized papain.  The inhibitors were mainly localized in lysosomal, microsomal and cytosol fractions, whereas their specificity towards papain and lysosomal thiol-dependent proteinases cathepsins B, L, H and C was dissimilar, thus suggesting presence of various forms of inhibitors of thiol-dependent proteinases in these cell fractions.