Pharmacological assay of Casearia sylvestris. I: Preventive anti-ulcer activity and toxicity of the leaf crude extract.

An ethanol extract of the leaves of Brazilian Casearia sylvestris, given orally, inhibited gastric secretion in pylorus-ligated rats. At a prophylactic dose of 57.5 mg/kg, the extract showed a reduction of gastric juice more effective than misoprostol (500 micrograms/kg). In reducing hydrochloric acid output, the extract was less effective than misoprostol, cimetidine (32.0 mg/kg) and atropine (5.3 mg/kg). With the extract, the pH of the stomach contents was not significantly different from that of controls. Stress-induced lesions produced by restraint and water immersion were significantly prevented by the extract for all levels of severity when compared with the controls. The extract appeared more effective than misoprostol in suppressing light lesions, was equivalent to cimetidine and misoprostol for moderate lesions, and less effective than cimetidine and misoprostol for severe lesions. Toxicological experiments indicated a low acute toxicity, confirmed by subchronic daily testing. The oral LD50 value of greater than 1840 mg/kg was over 32 times higher than the antiulcerogenic ED50 (57.5 mg/kg).