gamma-Dichroine, the antimalarial alkaloid of ch'ang shan.

Abstract

1. γ-Dichroine, an alkaloid of Ch`ang Shan, has a Q value of 148 against Plasmodium lophurae in ducklings, and a Q value of 137 against P. relictum in canaries. It is also active against P. cynomolgi in monkeys. 2. γ-Dichroine in a single dose is approximately 3½ times as toxic to mice by mouth than by vein. Repeated administration of γ-dichroine in mice may result in hydropic degeneration of the liver. 3. γ-Dichroine induces vomiting in pigeons following intravenous injection, the EmD 50 ± S. E. being 0.132 ± 0.04 mgm. per kgm. 4. γ-Dichroine has no effect on blood pressure and respiration in anesthetized dogs in the dose of 2.5 mgm. per kgm., but slightly lowers blood pressure with an acceleration of the respiratory rate in the dose of 4 mgm. per kgm. 5. γ-Dichroine stimulates duodenal peristalsis in anesthetized dogs, but inhibits the activity of the isolated rabbit9s ileum. It causes diarrhea in nonanesthetized rabbits and rats following intravenous injection. 6. γ-Dichroine produces hyperglycemia in rabbits in the dose of 2.5 mgm. per kgm. when injected intravenously. In rats, the same dose when given by mouth shows a slightly greater antipyretic action than acetylsalicylic acid.