Toxicity of pure alkaloid of Tylophora asthamatica in male rat.

Administration of pure alkaloid of T. asthamatica, suspended in peanut oil and given in single doses (12-100 mg/kg) by gavage, to male rats caused inactivity, respiratory distress, salivation, nasal discharge and diarrhoea. The oral LD50 value of the alkaloid was 35.32 mg/kg. In short term toxicity study daily doses of the alkaloid (1.25, 2.5, 5 and 10 mg/kg) were given to male rats for 15 days. Smaller doses of the alkaloid (1.25 and 2.5 mg/kg/day) produced no signs of poisoning or death in animals; while 5 mg/kg/day produced signs of poisoning and death of two animals, 10 mg/kg/day caused death of all the animals within 7 days. Activities of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and alkaline phosphatase were significant and associated with morphological changes in liver. The alkaloid also caused marked changes in the morphology of seminiferous tubules and spermatogenic activity of experimental animals. Since the alkaloid is effective in microgram quantities, the non toxic effects observed after daily doses of 1.25 mg/kg in male rats assume great therapeutic significance.