HYPOTENSIVE AND SPASMOLYTIC ACTIVITIES OF ETHANOLIC EXTRACT OF CAPPARIS-CARTILAGINEA

An ethanolic extract of Capparis cartilaginea (CC) at a dose of 1-10 m g/kg caused a dose-dependent fall in blood pressure and heart rate in anaesthetized rats. These effects were not blocked by atropine (1 mg/k g) and pretreatment with CC did not alter the presser response to nore pinephrine, indicating that the cardiovascular effects of CC are indep endent of cholinergic or adrenergic receptor involvement. In spontaneo usly beating guinea-pig atria, CC induced a concentration-dependent (0 .1-1 mg/mL) decrease in force and rate of atrial contractions. In rabb it thoracic aorta, CC caused inhibition of norepinephrine or K+-induce d contractions. In guinea-pig ileum, CC (1 mg/mL) inhibited submaximal contractions induced by acetylcholine, histamine or 5-HT. Spontaneous contractions of rat uterus were also abolished when CC was added to t he tissue bath at similar concentrations. These results suggest that t he direct relaxant action of CC on myocardium and blood vessels may be responsible for its hypotensive and bradycardiac effects observed in the in vivo studies. Moreover, CC exhibits general spasmolytic activit y in different smooth muscle preparations.