Pharmaceutical Sciences Faculty Publications

Title

Hypotensive Activity of the Ethanol Extract of Pavetta crassipes Leaves

Document Type

Article

Publication Date

12-2003

Journal Title

Biological and Pharmaceutical Bulletin

Volume

26

Issue

12

First Page

1674

Last Page

1680

DOI

10.1248/bpb.26.1674

Abstract

Pavetta crassipes leaf is routinely used locally in Nigeria for the management of respiratory disorders and hypertension. The hypotensive and other cardiovascular effects of Pavetta crassipes were investigated in cats and rats. The effects of the extract on rat and cat blood pressures, isolated rat atria, rat portal vein, isolated rat aorta and rat vas deferens were studied. Specific receptor antagonists (atropine, mepyramine, phentolamine, propranolol) were used to elucidate the underlying mechanism(s) involved in the cardiovascular changes induced by P. crassipes. The results revealed that the ethanolic extract of Pavetta crassipeslowered the blood pressures of cats and rats in a dose dependent manner. The extract also caused a concentration-dependent decrease in the force of contraction of the isolated rat atria and rat portal vein. The decreases in blood pressure values were attenuated in the presence of a β-adrenoceptor antagonist, propranolol. The extract also attenuated isoprenaline-induced contraction of the rat atria. However, the extract did not affect contractions evoked by KCl, norepinephrine and 5-HT on the rat aorta. Pavetta crassipescontains biologically active substances that may be useful in the management of hypertension.

Keywords

Pavetta crassipes, hypotension, rat atria, rat portal vein, cardiovascular activity