Monocrotaline is an 11-membered macrocyclic pyrrolizidine alkaloid derived from members of the Crotolaria species, long
known to cause poisoining among livestock. Monocrotaline causes pulmonary artery hypertension, right ventricular
hypertrophy, and pathological changes in the pulmonary vasculature in rats. Cardiopulmonary changes induced by
monocrotaline are attenuated by treatment with oral magnesium. Monocrotaline is used in animal models of pulmonary arterial hypertension