Effect of trimebutine maleate on the contractile response of the isolated ileum from diabetic rats

Abstract 1. 1. Tension of the isolated ileum from diabetic rats induced by streptozotocin was measured isometrically to study the mode of action of trimebutine maleate (TMB). 2. 2. The hyperreactivity of contractile response to KCl was observed in the isolated ileum from diabetic rats. TMB inhibited the contraction induced by KCl and acetylcholine (ACh) in normal solution. 3. 3. In Ca 2+ free solution, the hyperreactivity of contractile response to KCl was attenuated, and TMB did not inhibit the contraction induced by KCl. In contrast, TMB inhibited the contraction induced by ACh even in Ca 2+ free solution. 4. 4. These results suggest that the hyperreactivity of contractile response to KCl in the ileum from diabetic rats is due to the enhancement of Ca 2+ influx through voltage-dependent Ca 2+ channel and that TMB inhibits the hyperreactivity of contractile response through the inhibition of Ca 2+ movement by the cell.