[Reaction between x-ray contrast media and dyes and hepatocyte plasma membranes]

It has been shown in experiments in vitro that the hepatotrophic organic anions, the radiographic contrast agent (RCA) bilignost used in cholecystography and Bengal pink, have an affinity, unlike the urographic RCA triombrin and renotrophic dye indigo-carmine, for the plasmatic membranes (PM) of liver cells. Hydrophobic interaction has been ascertained to be of primary importance in the course of Bengal pink binding to PM of hepatocytes. PM has a higher capacity for binding Bengal pink as compared to that of lysosomal and microsomal membranes of liver cells. The binding capacity of uterine and renal PM is about 2.5 and 3 times less, respectively than that of liver PM, that is accounted for by differences in the number of binding sites on the membranes with a similar affinity for the dye. The results obtained indicate that PM of liver cells carry specific binding sites responsible for recognition and selective absorption of the hepatotrophic organic anions.