Abstract
We injected [C]-phosphatidylcholine (PC) -labelled lipo-heparin into rats to investigate the prolonged effect of lipo-heparin in vivo.The radioactivity of [C]-PC in plasma was cleared very rapidly from the circulation (about 5% of the injected dose at 5min) whereas the anticoagulant activity of heparin remained until 90min. The degradation of [C]-PC in plasma was not detected by TLC. However, almost all radioactivity was taken up in 10min by liver and spleen suggesting that the prolonged effect of lipo-heparin may be due to the gradual release of heparin from liposomes entrapped in those organs.
