Prostaglandin E1 incorporated in lipid microspheres (lipo PGE1).

Prostaglandin E1 (PGE1) was incorporated into soybean oil microspheres 0.2 micron in diameter, using lecithin as surfactant. The pharmacological effects of this new galenic form of PGE1 (lipo PGE1) was evaluated in experimental peripheral arterial occlusive disease in rats and in an ex vivo antithrombosis test in rats. It was shown in the experiments that lipo PGE1 had a more marked protective effect in arterial occlusive tissue injury caused by lauric acid and a more potent platelet aggregation inhibitory effect than PGE1. Total radioisotope activity of 3H-PGE1 in lipid microspheres in blood was higher and persisted longer than that of PGE1 in rats. These results suggested that the favourable features of lipo PGE1 depended on protection against inactivation in the lung and its targeting effect to tissues injured by arterial occlusion.