Spasmolytic actions of active principles of volatile oil of acorus gramineus

Three active principles, a-asarone (1), [3-asarone (Il) and l-allyl-2,4, 5-trimethoxybenzene (III), obtained from Acorus gramineus were found to possess spasmolytic action on isolated guinea pig's trachea and ileum against the spasmogenq acetylcholine (ACh), histamine (Hist), se-rotonin (5-HT), and BaClz. Out of these 3 compounds, I was most effective with the minimal effective concentrations of lO ug/ml against ACh,Hist and 5-HT on trachea; 10 ht9/ml against ACh, 20 ug/ml against Hist, 10 ug/ml against 5-HT, and 80 ug/ml against BaCl2 0n ileum. The concentra-tions of I for complete blocking action against spasmogens were 40 u. g/ml against ACh, 80 Vg/ml against Hist, and 53 ug/ml against 5-HT on trachea. II andⅢ were less potent than l. Dandiya et al reported in 1964 that I (3 0r 6mg/kg) possessed many neuropharmacological properties similar to chlorpromazine and reserpine. These properties were not reproduced even with the doses of 24 and 48 mg/kg in our laboratory except I potentiated pentobar-bital-induced hypnosis.