RESUMO
This study was carried to examine the effects of the aqueous leaf extract of Sesamum radiatum, a laxative plant on the contractile activity of Taenia caeci, an intestinal smooth muscle. Strips of Taenia caeci were rapidly removed from guinea-pig and were suspended between two L-shaped stainless steel hooks in a 10 ml organ bath with Mac Ewen solution. The isometric contractile force of the Taenia caeci strips were recorded by using a strain gauge. S. radiatum aqueous leaf extract (ESera) is a spasmogenic substance. This myostimulant effect is characterized by the increase of the rhythm and the amplitude of isolated guinea-pig Taenia caeci smooth muscle in normal solution and by the development of contracture in modified solution and in solution without calcium. A similar effect was observed with ACh which caused a graded increase of the contractile activity of Taenia caeci. The effects induced by ESera and ACh were reversed in the presence of atropine. The spasmogenic effect induced by ESera could justify partially the use of S. radiatum as laxative in traditional medicine.
