The effect of internal biliary drainage on bile pigment accumulation and acid phosphatase activity in human liver...

The effect of internal drainage after biliary obstruction due to primary cholangiocarcinoma has been studied in seven human liver biopsies with respect to bile pigment accumulation and acid phosphatase activity. Enzyme activity was demonstrated at the light-microscopic level in unfixed cryostat sections using an incubation medium containing naphthol AS-BI phosphate as substrate, and hexazotised pararosaniline as simultaneous coupling agent, and at the ultrastructural level in fixed tissue blocks and chopped tissue sections using sodium beta-glycerophosphate as substrate and lead or cerium ions as capture reagent. Large amounts of bilirubin were found in cryostat sections of non-drained cholestatic livers, especially in pericentral areas. At these sites a high acid phosphatase activity was found. At the ultrastructural level, acid phosphatase activity was found only in the lysosomal compartment--possibly due to the procedure necessary for tissue processing. After internal biliary drainage, the amount of bilirubin diminished, with a concomitant decrease in acid phosphatase activity. The co-localization of accumulations of bile compounds and acid phosphatase activity indicates that lysosomes play a role in the breakdown of bile compounds.