THE INTERACTION OF GADOLINIUM COMPLEXES WITH ISOLATED RAT HEPATOCYTES

The lanthanide metal, gadolinium, is currently used in contrast agents for magnetic resonance imaging. We have performed a study of the interaction between isolated rat hepatocytes and Gd-153 complexed to diethylene-triamine pentaacetic acid (DTPA) or to DTPA-albumin conjugates. The study shows that isolated hepatocytes are able to take up both types of Gd-153 complexes. The Gd-153-DTPA-albumin complexes are apparently taken up by pinocytosis, and possibly receptor-mediated endocytosis and/or adsorptive endocytosis, whereas the uptake mechanism of Gd-153-DTPA is unknown. The Gd-153-DTPA-albumin complexes, but not the Gd-153-DTPA complex, are degraded by the cell. The degradation is inhibited by ammonium chloride, Gadolinium is slowly released back to the medium after loading of the cells with both complex types. In the experiments reported here no evidence of any adverse effects on the hepatocyte resulting from exposure to the Gd-153-complexes were observed.