RESUMEN
Studies were undertaken on the effect of a crude (TC) and an alkaloid fraction (TA) of the leaf extracts of Tylophora conspicua on indomethacin-induced gastric ulceration and gastric acid secretion in male albino rats. Both the TC and TA produced a dose-dependent inhibition of gastric ulceration. At a dose level of 40 mg/kg TC and TA were more effective (TA being more potent) than propranolol in inhibiting gastric ulceration. The highest dose of the extracts used (80 mg/kg) completely inhibited gastric ulceration. Intravenous administration of the TC and TA significantly decreased acid output at low dose (20 mg/kg), medium dose (40 mg/kg) and high dose (80 mg/kg) from the peak basal of 0.54 +/- 0.02 mEq/L/min to 0. 49 +/- 0.02 mEq/L/min, 0.35 +/- 0.01 mEq/L/min and 0.21 +/- 0.02 Meq/L/min respectively. 80 mg/kg of TC and TA significantly reduced the histamine (1 mg/kg) induced gastric acid secretion. The results suggest that the antiulcer activity of Tylophora conspicua might be produced by gastric acid inhibition.