Effects of organic anions and bile acids on hepatocellular uptake of lithocholate-3-sulfate

Abstract We previously reported that hepatic uptake of lithocholate-3-sulfate is mediated by a Na + -independent system, as has been reported with various organic anions and unconjugated bile acids. Herein, we examined the effects of organic anions and bile acids on hepatic lithocholate-3-sulfate uptake using isolated rat hepatocytes. Lithocholate-3-sulfate uptake was inhibited by sulfobromophthalein, indocyanine green and rose bengal. By contrast, lithocholate-3-sulfate uptake was not inhibited by dibromosulfophthalein, the uptake of which has been reported to be ATP-dependent, or by cholate. Cellular ATP depletion had no effect on lithocholate-3-sulfate uptake. These findings suggest that hepatic lithocholate-3-sulfate uptake is mediated by a Na + -independent system common for organic anions such as sulfobromophthalein, which is not facilitated by ATP.