Some haemodynamic effects of nicergoline, a new alpha-blocking agent, in the closed-chest anaesthetized dog as compared with nitroprusside and nitroglycerin.

Considering the recent rediscovery of the use of alpha-blocking agents in the treatment of hypertension and heart failure, we have studied the haemodynamic effects of 10-methyl-1,6-dimethyl-ergoline-8 beta-methanol-(5-bromonicotinate (nicergoline, Sermion), a new alpha-blocking ergot derivative, on the closed-chest anesthetized dog. For comparative reasons, the effects of nitroglycerin and nitroprusside were studied on the same model. The doses were adjusted to give an identical decrease in blood pressure after 30 min infusion (nearly 30%). Nicergoline did not change the heart rate, decreased total and femoral arterial resistance, did not change the cardiac output or the femoral flow, as opposed to nitroglycerin which decreased the cardiac output and systolic volume, causing a reflex tachycardia and femoral constriction, confirming its predominantly venous effect. Nitroprusside did not cause tachycardia, and the femoral resistances were increased, though less so than with nitroglycerin. Both nitroglycerin and nitroprusside apparently had no direct effect on myocardial performance, whilst nicergoline seemed to increase the myocardial compliance (by a decrease of the sympathetic tone). This drug merits further attention in that it is readily soluble and can easily be administered i.v., for treatment of acute heart failure, for example.