Effects of extract from Clerodendron trichotomum on blood pressure and renal function in rats and dogs.

Clerodendron trichotomum Thunb. is a herb which has been used for treatment of hypertension in Chinese medicine. To assess the action of the herb on blood pressure and renal function, the extract was administered to rats and dogs. Intravenous administration of the extract elicited renal vasodilation and increased urine flow and urinary sodium excretion. Acute oral administration of the extract reduced blood pressure of spontaneously hypertensive rats but not of normotensive control rats. Chronic daily administration for 6 weeks prevented the increase in blood pressure of spontaneously hypertensive rats. These results may give some support to the claim on the clinical efficacy of the extract of Clerodendron trichotomum Thunb.