Influence of a portacaval shunt on the distribution of 14C-chol-PC-DCP-liposomes and liposome entrapped 3H-methotrexate in the organs of rats.

The individual roles of hepatic parenchymal cells and non-parenchymal cells in the uptake of intravenously injected liposomes by the liver have not yet been clearly determined. Experimentally, it is suggested that a portacaval shunt reduces the phagocytic capacity of the liver RES. In our experiments a portacaval shunt does not influence the hepatic uptake of 14C-Chol-PC-DCP-liposomes and the liposome entrapped 3H-Methotrexate in rats. In normal rats and in rats with a portacaval shunt, most of the 14C- and 3H-radioactivity is found in the liver and the ratio between the amounts of free and liposome entrapped radioactivity 3 to 15 hours after i.v. injection is approximately 1:10. Therefore, it is concluded that the liver RES does not play an integral role in the enrichment of liposomes in the liver.