Monocrotaline is an pyrrolizidine alkaloid extracted from the seeds of the Crotalaria spectabilis plant to induce pulmonary hypertension in rodents. In Vitro: Monocrotaline (MCT) is an 11-membered macrocyclic pyrrolizidine alkaloid (PA) derived from the seeds of the Crotalaria spectabilis plant^[1]. Monocrotaline a natural ligand exhibits dose-dependent cytotoxicity with potent antineoplastic activity. The in vitro cytotoxicity of monocrotaline is proved at IC₅₀ 24.966 µg/mL and genotoxicity at 2 X IC₅₀ against HepG2 cells^[2]. In Vivo: MCT causes a pulmonary vascular syndrome in rats characterized by proliferative pulmonary vasculitis, pulmonary hypertension (PH), and cor pulmonale^[3]. Among preclinical models of pulmonary arterial hypertension (PAH), monocrotaline animal model offers the advantage of mimic several key aspects of human PAH, including vascular remodeling, proliferation of smooth muscle cells, endothelial dysfunction, upregulation of inflammatory cytokines, and right ventricle failure, requiring a single drug injection^[4]. Changes in multiple pathways associated with the development of PH, including activated glycolysis, increased markers of proliferation, disruptions in carnitine homeostasis, increased inflammatory and fibrosis biomarkers, and a reduction in glutathione biosynthesis are observed with the injection of monocrotaline^[5].