RESUMO
The aim of this study is to detect the pharmacological effect of aloe [fresh plant and dried Aloe socotrana], gall and the extract of khat leaves [Catha edulis Forsk] on the isolated rabbit duodenum. Extracts of aloe, gall and khat leaves were assayed using isolated rabbit duodenum technique. Mechanical activity of the tissue was registered with a frontal ink isotonic lever on a kymograph drum under continuous oxygen bubbling. The aqueous extract of gall showed a contraction, which was persistent after incubating the tissue with atropine. Fresh extract from the plant aloe as well as aqueous extract of the dried aloe reduced the tone of the mechanical activity of the isolated rabbit tissue. Incubating the tissue with propranolol did not change this response. Ethyl acetate extract of khat leaves from Aldhalae and Yafae provinces did not modify the tone of the tissue, but Yafae khat extract changed the motility. The findings suggest that the gall induced contraction was not based on cholinergic activity, while relaxation, produced by aloe, seemed not to be associated with adrenergic agonism. Yafae khat leaves disturbed the mechanical activity of the tissue