Hypotensive effect of dehydroevodiamine from Evodiae Fructus.

Dehydroevodiamine isolated from Evodiae Fructus lowered blood pressure with bradycardia in anesthetised rats. At a cumulative dose of 22.5mg/kg/30min, there was a very significant decrease in blood pressure and heart rate. There was a more important decrease in diastolic pressure than systolic pressure, implying a vasodilatory effect. The hypotensive effect of dehydroevodiamine can be abolished partly by indomethacin and more completely, polyphoretin phosphate. It is suggested that the hypotensive effect of dehydroevodiamine may be mediated through prostaglandin synthesis. A similar action mechanism in dehydroevodiamine-stimulated rat uterus contraction is also discussed.