Effect of chenodeoxycholic acid on liver structure and function in man: a stereological and biochemical study.

Chenodeoxycholic acid (CDCA) is an effective treatment for dissolving gallstones but experimental studies have suggested that it might be hepatotoxic. The present study is concerned with a group of patients undergoing medical therapy for gallstones for periods of 30 days up to 14 months with CDCA (15 mg/kg/day). Routine functional tests, determination of some liver microsomal enzymes and stereological studies of the liver tissue have been performed and the data have been compared with those obtained before treatment. No significant changes were observed in the functional tests throughout the study. Also the microsomal mixed function oxidase system seemed unaffected by CDCA therapy. The histological features of the liver biopsies were not appreciably different from those observed prior to treatment. Although there were large interindividual variations, the volume density of parenchymal steatosis and of the lipocytes remained comparable in the ssme individual. The ultrastructural features noted in untreated subjects such as curled mitochondrial cristae, slight intracellular bile retention, increased surface density of the rough endoplasmic reticulum were still evident after 14 months of treatment. No additional changes were noted. These results show that no evidence of hepatotoxicity seems to develop in man under therapy with CDCA at the dose considered. But the structural abnormalities observed before treatment appear to persist even in subjects under long-term therapy.