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 inte raction between isolated rat hepatocytes and Gd-153 complexed to dieth ylene-triamine pentaacetic acid (DTPA) or to DTPA-albumin conjugates. The study shows that isolated hepatocytes are able to take up both typ es of Gd-153 complexes. The Gd-153-DTPA-albumin complexes are apparent ly 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-15 3-DTPA complex, are degraded by the cell. The degradation is inhibited by ammonium chloride, Gadolinium is slowly released back to the mediu m after loading of the cells with both complex types. In the experimen ts reported here no evidence of any adverse effects on the hepatocyte resulting from exposure to the Gd-153-complexes were observed.