Ethnopharmacological evaluation of antisplasmodic activity of essential oils from different plants

Achillea santolina, Nepeta cataria and Salvia bucharica are mainly known to possess antispasmodic use in traditional medicine. The essential oils from these plants were screened for their possible pharmacological activity with possible mode of action explored. Volatile oil was extracted by steam distillation using standard procedure given in British Pharmacopoeia 2001. For pharmacological activity, rabbits were killed by cervical dislocation and jejunum was dissected out. About 2 cm pieces of rabbit jejunum were suspended separately in 10 ml isolated tissue baths containing Tyrode’s solution maintained at 37?C and aerated with carbogen. The responses were recorded on the Harvard Student Oscillograph. The oils, after solubilizing in different solvent systems according to their solubility, showed dose-dependent relaxation of spontaneous contractions of rabbit jejunum thus showing spasmolytic activity. The effect was dose-dependent, mediated at the dose range of 0.01-0.3 mg/ml. When tested on high K+ (80 mM)-induced contractions, the oils from all plants showed varying degree of relaxant effect observed at the dose range of 0.01-0.3 mg/ml. This study indicates that the spasmolytic effect is mediated through the presence of calcium channel blocking constituents in these plants, and thus provides sound scientific base for some of the traditional uses of the plants.