[The effect of etilefrine and dihydroergotamine on sympathetic nervous system activity when standing up (author's...

Systolic blood pressure, heart rate and concentrations of adrenaline, noradrenaline and dopamine as well as plasma dopamine-beta-hydroxylase (DBH) were measured in 22 subjects in recumbency and on standing up. Six subjects each had previously been given intravenously dihydroergotamine (0.5 mg) or etilefrine (0.25 mg/min) or a placebo. It was demonstrated that orthostasis leads to an increased activity of the sympathetic nervous system and the adrenal system. After administration of dihydroergotamine there was a diminished reaction of the sympathetic nervous system with an increase of venous tone which counteracted the decrease in cardiac output. Etilefrine, on the other hand, inhibited the sympatho-adrenal reaction on orthostasis and decreased the liberation of adrenaline. It acts directly via stimulation of alpha-and beta-receptors and is thus predominantly indicated if there is insufficient response of the baroreceptor reflex at its efferent limb.