Sampatrilat (UK-81252) is a potent and orally active vasopeptidase inhibitor of ACE and neutral endopeptidase (NEP). Sampatrilat inhibits C-domain ACE (K_i=13.8 nM) 12.4-fold more potent than that for the N-domain (K_i=171.9 nM). Sampatrilat (UK-81252) can be used for the study of chronic heart failure and blood pressure regulation^[1][2]. IC50 & Target: Ki: 13.8 nM (cACE); 171.9 nM (nACE)^[1] In Vivo: Sampatrilat (oral adminstration; 30 mg/kg; once a day; 5 weeks) reduces the mortality of the rats with CAL (20% versus 57% for untreated rats) and increase in the survival rate and improvement of hemodynamic function of the rats with CAL. This compound suppresses tissue ACE and neutral endopeptidase (NEP) activities, but it does not affect the arterial blood pressure, whereas it attenuates the CAL-induced increases in the left ventricular end-diastolic pressure, heart weight, and collagen content of the viable left Ventricle^[2].