Negative inotropic and vasoconstrictor effects of oxidized phospholipids

: Effects of oxidized yolk phospholipids (PL) on the coronary perfusion rate (CPR) and myocardial contractility were studied in the experiments with the isolated or isolated and 30-minute ischemia-induced heart of the rat or isolated myocardial strip of the frog. The oxidized PL were demonstrated to possess a more pronounced and steady negative inotropic effect than unoxidized PL, which was due to their direct dose-dependent damaging action on myocardial contractility. The oxidized PL also made the unrestored CPR worse in the early postischemic period, the concomitant administration of aspirin producing no effects and that of the antioxidant ionol making ischemic myocardial contractility better. The findings suggest that the circulating oxidized PL may contribute to the impairment of coronary tone and contractility of the intact or ischemic myocardium and the induction of endogenous processes of lipid peroxidation plays a role in showing these effects.