Palosuran is an antagonist of the urotensin II receptor (UTR; IC50s = 3.6 and 1,475 nM for CHO cell membranes expressing human and rat recombinant receptors, respectively). It inhibits contraction of isolated rat aortic rings induced by urotensin II (Item Nos. 24711 | 24753) in a concentration-dependent manner. Palosuran (300 mg/kg twice per day) reduces plasma endothelin-1 , urotensin II, and TGF-β1 levels, as well as the main pulmonary arterial pressure and right ventricular hypertrophy index in a rat model of pulmonary arterial hypertension (PAH) induced by monocrotaline . Palosuran (300 mg/kg per day) reduces serum glucose, cholesterol, and triglyceride levels and increases survival in a rat model of diabetes induced by streptozotocin (STZ; ). It also decreases albuminuria and global kidney lesion scores in STZ-induced diabetic rats.