Suppressive Effect of Ethanol on the Expression of Asialoglycoprotein Receptors in a Human Hepatoma Cell Line

We studied the effect of ethanol on the expression of asialoglycoprotein receptors of a human hepatoblastoma cell line, Hep G2, which has been shown to maintain a large variety of normal hepatocyte functions. By culturing cells in the presence of ethanol, the number of asialo- glycoprotein receptors on the cell surface decreased to 60% of that of the control, with no significant change of binding affinity. The decreased expression of cell surface receptors was parallel to that of total receptor number including surface and intracellular receptors. The internalization was also inhibited to 44% of that of control cells by ethanol treatment. This cell line possessed as much alcohol dehydrogenase activity as normal human hepatocytes and the decrease in number of asialoglycoprotein receptors was partially recovered by the concomitant use of alcohol dehydrogenase inhibitor, 4-methylpyrazole