Abstract
Objective: To study the possible effects of methanolic extract of fruits of Tamarindus indica on rabbit′s jejunum preparations. Materials and Methods: The study was carried out on rabbit′s jejunum preparations. Methanolic extract of fruits of T. indica was applied in different doses. Potassium chloride (KCl 80 mM)-induced contractions were relaxed by the extract. For determination of possible mode of action of relaxing effects, calcium chloride curves were constructed in decalcified tissues using K + normal and followed by K + rich solution. The curves were then compared with verapamil. Results: Relaxant effects on KCl-induced contractions were prominent at a concentration of 5.0-10.0 mg/ml (P<0.05). A right shift at a concentration of 3.0 mg/ml (EC 50 ± SEM = 1.98 ± 0.03) and 10.0 mg/ml (EC 50 ± SEM = 1.79 ± 0.05) versus control (EC 50 ± SEM = 2.33 ± 0.058) resembled the effects of verapamil on the calcium chloride curves. Conclusion: The results confirmed its possible mode of relaxing effects i.e. through calcium channel blockade.