1982 Volume 30 Issue 6 Pages 2248-2251
Liposomes composed of dipalmitoylphosphatidylcholine (DPPC) labeled with L-α-[dipalmitoyl-1-14C]-phosphatidylcholine ([14C]-DPPC) and cholesterol (molar ratio 7 : 2) were injected into rats intratracheally. The lungs took up about 90% of administered [14C]-DPPC and 50% of liposomal DPPC was retained for over 24 h. In contrast, uptake by the liver and kidney after intravenous administration was high and uptake by the lung was negligible. Uptake of [14C]-DPPC by lung lamellar bodies was higher than that by other lung subcellular fractions (mitochondria, microsomes and soluble fractions). From the results of histochemical investigation, it was found that the liposomes were taken up uniformly by the lung.