A pharmacological evidence for the presence of antihistaminic and anticholinergic activities in Equisetum debile Roxb

OBJECTIVE: The study was designed to evaluate possible antihistaminic and anticholinergic activities of Equisetum debile. MATERIALS AND METHODS: Effects of crude ethanolic (Ed.Eth) and effects of crude aqueous (Ed.Aq) extracts of E. debile were studied using isolated guinea pig ileum, rabbit jejunum, and rabbit trachea. Tissue responses were recorded using isotonic and isometric transducers, connected with PowerLab data acquisition system. RESULTS: A dose-dependent (0.1–0.3 mg/ml) rightward shift was demonstrated in histamine concentration-response curves. Whereas a complete relaxation of carbachol (1 μM)-induced contractions in isolated rabbit jejunum (3 mg/ml) and tracheal (10 mg/ml) preparations was observed, similar to dicyclomine at 1 and 3 μM, respectively. However, no significant difference between the effects of Ed.Eth and Ed.Aq was observed. CONCLUSION: Study provides pharmacological evidence for the presence of antihistaminic and anticholinergic activities in crude extracts of E. debile and also highlight its medicinal significance in the management of airway and gastrointestinal disorders.