A postcoupling method for the demonstration of N-acetyl-beta-D-glucosaminidase in unfixed frozen tissue sections

The localization and activity of the lysosomal enzyme, N-acetyl-beta-glucosaminidase, has been studied in unfixed frozen sections of tissues from normal and hemorrhaged rats with the use of a modified postcoupling technique. Discrete localization of the end product of the reaction was achieved in this method by the incorporation of 20% (w/v) polyvinyl alcohol (molecular weight 14,000) in the incubation medium. Advantages of the present method include the ability to overcome the inhibitory effects on enzyme activity of both tissue fixation and the presence of diazonium salts in the incubation medium. The staining reaction obtained with this technique demonstrates the enzyme activity at specific cytoplasmic sites within cells and has a wider applicability to the comparative study of N-acetyl-beta-glucosaminidase activity in normal and injured tissues.