Monocrotaline-induced pulmonary arteritis in rats

Summary Ethanol-extracted Crotalaria spectabilis seeds when fed to immature rats are no longer toxic. Monocrotaline at concentrations of 20 or 30 mg/kg of food is capable of producing all of the tissue changes attributed to the ingestion of ground unextracted C. spectabilis seeds. Monocrotaline feeding in addition to producing hepatic necrosis, pulmonary hemorrhage or epithelial hyperplasia may also induce pulmonary arteritis. Treatment of the toxic alkaloid either by hydrogenolysis or Ba(OH) 2 hydrolysis is associated with loss of toxicity. These observations suggest that monocrotaline and not its derivatives is responsible for the toxicity encountered in C. spectabilis seeds.