EFFECTS OF DOPEXAMINE ON CARDIAC HEMODYNAMICS DURING MYOCARDIAL ISCHEMIA IN RATS AND IN COMPARISON WITH FENOLDOPAM AND PROCATEROL

The effect of dopexamine hydrochloride(DPX) on cardiac hemodynamics during acute myocardial ischemia(AMI) was studied in rats and compared with those of fenoldopam hydrochloride(FODA) and procaterol hydrochloride(PCT).The results showed that iv DPX remarkably attenuated the increases of total peripheral resistance(TPR) and left ventricular end diastolic pressure and the decreases of +dp/dt max caused by ischemia, while DPX showed no significant effect on mean arterial pressure(MAP). Although FODA was more potent than DPX in attenuating the increase of TPR and the decrease of myocardial contractility caused by ischemia, it significantly decreased MAP. The effects of PCT on all these variables were the smallest among the 3 agents.The results suggest that DPX has a better prospect in the treatment of ischemicheart disease in view of its actions of decreasing TPR, mild increase of myocardial contractility, without MAP decrease and myocardial oxygen consumption increase.