LYSOSOMAL-ENZYME ACTIVITIES IN GALLBLADDER MUCOSA OF GALLSTONE-FREE SUBJECTS AND PATIENTS WITH GALLSTONES

Background/Aims: Gallstone patients have a reduced cellular lysosome c ontent in the gallbladder mucosa cells compared with gallstone-free su bjects. The purpose of the study was to further evaluate the possible role of lysosomes in the pathogenesis of cholesterol gallstone formati on in humans. Methods: Lysosomal enzyme activities were assayed in gal lbladder mucosa and for comparison in liver specimens of 19 gallstone- free subjects and 24 gallstone patients undergoing cholecystectomy. Re sults: Gallstone patients had 25-50% lower activities of the lysosomal proteases cathepsin B, D and L in their gallbladder mucosa compared w ith gallstone-free subjects. The activity of acid phosphatase also ten ded to be decreased in gallstone patients. The liver lysosomal enzyme activities were not significantly different between the two groups. Co nclusions: The results show that gallstone patients have diminished ly sosomal enzyme activities in the gallbladder mucosa, a finding which m ay be related to decreased intracellular degradation of proteins and/o r mucin in the mucosal cells. This may lead to a higher concentration of mucin in gallbladder bile and thus an increased risk of precipitati on of cholesterol crystals and gallstone formation.