Comparative studies on the uptake of 14C-bile acids and 3H-demethylphalloin in isolated rat liver cells

The inward transport of bile acids in isolated hepatocytes competes with the uptake of phallotoxins. Cholate, taurocholate and glycocholate added 30 s prior to phallotoxins reduce their uptake in a concentration dependent manner. 100 M bile acids suppress the uptake of phallotoxins completely. Several compounds known to inhibit the bile acid transport reduce the phallotoxin uptake to a similar degree. Hepatocytes exposed to reagents reacting preferentially with amino groups of proteins lose their uptake of both bile acids and phallotoxins. In hepatocytes isolated from 5 day old rats the uptake of both phallotoxins and cholate is reduced as compared to cells from adult controls. AS-30D ascites hepatoma cells, known to be insensitive to phallotoxins are unable to take up both phallotoxins and cholate. The results are consistent with our working hypothesis of a very similar mechanism for the uptake of bile acids and phallotoxins.This work was supported by the Deutsche Forschungsgemeinschaft