KINETICS AND ORGAN DISTRIBUTION OF [C-14] SIALIC ACID-GM3 AND [H-3] SPHINGOSINE-GM1 AFTER INTRAVENOUS-INJECTION IN RATS

Serum kinetics and organ distribution of [14C]-sialic acid-GM3 and [3H]-sphingosine-GM1, administered as an intravenous bolus, were analysed in Wistar rats. [3H]-GM1 and [14C]-GM3 had serum half-lives of 1.4 hours and 1.8 hours, respectively. Three hours after injection 75% of the GM1- and 38% of the GM3-associated label were present in the liver. Smaller yet significant amounts of label were present in the central nervous system, kidneys and lung. In vitro studies showed that [14C]-GM3 and [3H]-GM1 incubated with serum were predominantly bound to the High Density Lipoprotein and the Low Density Lipoprotein fractions. These results suggest a rapid serum clearance of exogenous gangliosides by the liver in rats. © 1992.