Ethnopharmacological basis for the use of Valeriana wallichii in hypermotility disorders of the gut

The ethanolic crude extract of Valeriana wallichii rhizome (VwR.Cr) was studied in vitro for its possible antispasmodic activity to rationalize some of its folkloric uses. Segments of 2-3 cm long of rabbit jejunum preparations were mounted in Tyrode’s solution and aerated with 95% oxygen in carbon dioxide. Isotonic responses were measured on Bioscience oscillograph. VwR.Cr caused a dose-dependent (0.1-3.0 mg/mL) relaxation of spontaneous contractions of isolated rabbit jejunum. When tested against high K+ (80 mM) induced contraction, it was found devoid of any inhibitory effect up to the dose of 10.0 mg/mL, while it inhibited the low K+ (25 mM)-induced contractions at the dose range of 0.1-1.0 mg/mL. In the presence of glibenclamide (3 µM), the dose-response curves of low K+ (25 mM) were shifted to the right. These data indicate that VwR.Cr exhibits spasmolytic activity mediated possibly through the opening of glibenclamide-sensitive K+ channels, which may explain the traditional use of the Valeriana wallichii in the gastrointestinal disorders, like diarrhea and spasmodic conditions.