PHARMACOLOGICAL STUDIES ON COMMERCIAL "MO-TUNG"-A CHINESE DRUG FROM ARISTOLOCHIA MANSHURIENSIS KOMAROV

1. The commercial "Mo-tung", according to Jen's report, are stems mostly derived from the plant Aristolochia manslturiensis Komarov, and not from Akebia quinata Decne as was previously claimed. 2. The decoction of "Mo-tung" exerted a similar action on isolated heart of toads as in the case of digitalis. Small doses stimulated the heart by increasing force and amplitudes of contraction. Large doses inhibited heart by decreasing force of contraction and following standstill in diastole. Moderate doses prevented from complete dilatation of the ventricle; finally the heart stopped in ventricular systole and auricular diastole. 3. The action of the decoction of "Mo-tung" on toad's heart differred from that of calcium, but calcium ion caussd a synergising effect. 4. Small doses of "Mo-tung" decoction injected into the lymph sac of an anaesthetised toad, stimulated the heaft with increased amplitude of contraction. Large doses caused cardiac standstill in systole. 5. The decoction of "Mo-tung" stimulated isolated heart of a guinea pig by increasing the force of contraction and causing better systoles and diastoles. 6. In anaesthetised dogs and rabbits, intravenous injection of the decoction of "Mo-tung" decreased the amount of urine excreted for a short period. In authors' experiments, no sign of efficient diuretic effect was shown. 7. In anaesthetised dogs and rabbits, intravenous injection of the decoction of "Mo-tung" instantly raissd blood pressure which was followed by a decrease for a longer period. In certain rabbits, only fall of blood pressure was observed. 8. The decoction of "Mo-tung" stimulated isolated small intestines of mice. 9. The decoction of "Mo-tung" inhibited both non-pregnant and pregnant uteri of mice.