In 10 healthy subjects the injection of 10-methyl-1,6-diemthyl-ergoline-8 beta-methanol-(5-bromonicotinate (nicergoline, Sermion) (5 mg i.v.) caused a permanent decrease in blood pressure. This decrease in blood pressure is due to a rapidly occurring alpha-blocking effect and a secondary central alpha-stimulating effect which did not affect the postural regulating mechanisms of the arterial blood pressure in their function. The bradycardia and the elevation of the systolic volume and of the cardiac output are based on this central effect. After oral administration of 30 mg nicergoline the same modifications appeared but to a lesser extent. If nicergoline was administered in a dosage of 30 mg p.o. 1 h before bicyle exercise (100 W for 5 min), the cardiac output and blood flow in the lower extremities increased and the elevation of the systolic pressure was limited. However, the reactive tachycardia remained at the same level. The metabolic consequences of this administration resulted in an inhibited increase in the concentration of lactic acid in the blood, which is normally caused by this exertion. This favourable metabolic effect can be explained by 1. the initial bradycardia and the decrease in the total peripheral resistance whereby the oxygen consumption of the myocardium is reduced; 2. the peripheral vasodilation.