Pharmacological Activities of Psiadia punculata

Abstract

A 70% methanol extract of leaves of Psiadia punculata caused a fall of blood pressure in anaesthetised rats. After a 10 µg dose of the extract, systolic, diastolic and mean blood pressures fell by 16, 13 and 14%, respectively, below the pre-drum levels. The fall of systolic, diastolic and mean blood pressures in anaesthetised rats were 23, 14 and 19%, respectively, after a 60 µg dose of the extract. The post-drug blood pressure levels were significantly lower (P < 0.001) than the pre-drug levels. The plant extract showed neuromuscular blocking activity on isolated rat phrenic nerve diaphragm which was dose-related. The extract had bronchodilating properties on isolated guinea pig trachea, which was dose-dependent. The treatment of the rabbit jejunum with the plant extract in a calcium free Krebs solution, inhibited Ca 2+ ions to restore jejunum contractions, suggesting the extract had calcium channel blocking activity similar to that of verapamil, a known calcium channel blocker