PHARMACOLOGICAL ACTIONS OF TI TZAO, BULBUS OF SCILLA CHINENSIS (PRELIMINARY REPORT)

Ti Tzao, the bulbus of Scilia chinensis Benth. (Saila japonica Baker.) was described for the first time in Chiu-Hwang Pen T'sao (1406 A. D.) to be edible. The active constituent of the alcoholic extract of its leaves and rhizoma has been shown to be cardiotonic somewhat like the action of digitalis while tested on toad heart by the Straub method. It increased the force and prolonged the time of systolic contraction. It differs from digitalis in that the refractory period was not fully prolonged. The question whether the increased contractility of the heart was produced directly on the myocardium or indirectly through nervous regulation has not yet been ascertained. The alcoholic principle was found to be diuretic on the anesthetized dog. The mechanism of this action might be due to the cardiotonic action and the inhibiting action on the reabsorption function of renal tubules. The alcoholic extract also contained the oxytocic principle while tested on isolated mouse uterus. There were no effect on the blood pressure and respiration in the anesthetized dog with the dosage 1ml/g of 1:1 extract of leaves.