Ethyl 4-(4′-heptanoyloxyphenyl)-6-methyl-3,4-dihydropyrimidin-2-one-5-carboxylate Prevents Progression of Monocrotaline-induced Pulmonary Arterial Hypertension in Rats

Therapies to prevent onset and progression of pulmonary arterial pressure are not very effective yet. This study was designed to investigate the effects of a novel dihydropyrimidinone, ethyl 4-(4′-heptanoyloxyphenyl)-6methyl-3,4-dihydropyrimidin-2-one-5-carboxylate (H-DHPM) on pathogenesis of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). For the same purpose, rats were injected intraperitoneally (i.p.) a single dose (60 mg/kg) of MCT which led to development of PAH in 21 days. MCT insult caused high mortality, pulmonary vascular and parenchymal remodelling. Since the course of PAH pathogenesis is characterised by an early onset and progression phases, H-DHPM was administered i.p. at 30 mg/kg dosage in MCT pre-injected animals either from day 0 through day 21 or day 14 though day 21 of MCT injection in two separate treatment groups. H-DHPM significantly improved survival, prevented remodelling of pulmonary vasculature and parenchyma and subsequently ameliorated PAH pathogenesis. Moreover, we observed significant decrease in right ventricle hypertrophy, measured by wet weight of right ventricle (RV) divided by wet weight of left ventricle plus septum (LV+S), in H-DHPM treated groups as compared to MCT injected animals. These findings suggest H-DHPM not only prevented development of PAH but also treated the PAH pathogenesis in progressive phase. In conclusion, our data determines H-DHPM, might be a future drug for the prevention of PAH.