Pharmacokinetics and metabolism of i.m. injected polyenylphosphatidylcholine liposomes.
The pharmacokinetics of i.m. applied polyenylphosphatidylcholine liposomes has been investigated in rats with the aid of 3H- and 14C-labelled di-linoleoyl-sn-glycerophosphocholine. The experiments stated an efflux of polyenylphosphatidylcholine from muscle injection site with a half-life of 8.6 h. The analysis of remaining polyenylphosphatidylcholine at muscle injection site showed the great stability of this substance. After 24 h approximately 60% of remaining polyenylphosphatidylcholine are not disintegrated. Polyenylphosphatidylcholine was transported mainly to liver by high-density lipoproteins and other fractions with greater density. The rate constants were calculated. Approximately 50% of applied polyenylphosphatidylcholine were incorporated into liver as intact di-linoleoyl-sn-glycerophosphocholine. Hydrolyzed fatty acids form triglycerides and cholesterolesters whereas lyso-phosphatidylcholine is reesterified to phosphatidylcholine again.
D000818:Animals; D001798:Blood Proteins / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D007273:Injections, Intramuscular; D007700:Kinetics; D008074:Lipoproteins / Q000097:blood; D008081:Liposomes / Q000008:administration & dosage / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D009132:Muscles / Q000378:metabolism; D010713:Phosphatidylcholines / Q000008:administration & dosage / Q000378:metabolism*; D051381:Rats; D014018:Tissue Distribution
D001798:Blood Proteins; D005227:Fatty Acids; D008074:Lipoproteins; D008081:Liposomes; D010713:Phosphatidylcholines