Antispasmodic Effects of Bauhinia microstachya. on Isolated Smooth Muscle

Abstract Bauhinia microstachya. (Raddi) Macbr. (Leguminosae) is a Brazilian medicinal plant used in folk medicine to treat several ailments, including kidney disorders. This study reports on the evaluation of a methanol extract and ethyl acetate fraction from the leaves of this plant against two isolated smooth muscles, guinea-pig ileum and rat uterus, precontracted by acetylcholine, bradykinin, oxytocin, and calcium chloride. The results indicated that both caused noncompetitive antagonism and concentration-dependent relaxation against all the neurotransmitters tested without selectivity. The ethyl acetate fraction demonstrated the most pronounced antispasmodic effect, suggesting that the phenol compounds are the main active components of this plant. These results support and justify the popular use of this plant for the treatment of kidney problems.