P-7: The effects of vasopeptidase inhibitor omapatrilat on cardiac hypertrophy and brain natriuretic peptide concentration in spontaneously hypertensive rats

Omapatrilat is a newly developed vasopeptidase inhibitor (VPI) which displays equipotent, highly selective competitive activity against neutral endopeptidase (NEP) and angiotensin-converting enzyme (ACE). Simultaneous inhibition of NEP and ACE increases natriuretic and vasodilatory peptides including brain natriuretic peptide (BNP). The purpose of current study was to investigate the effect of omapatrilat on cardiac function as well as plasma and cardiac BNP level in spontaneously hypertensive rats (SHR). Studies were performed in SHR which received vehicle (n=9), omapatrilat (VPI, n=10) or fosinopril (ACEI, n=8) by daily gavage for six-month. Mean blood pressure (MBP) were measured by tail plethysmography. Left ventricular (LV) fractional shortening (FS) and LV mass were measured by echocardiography. Plasma BNP concentration was determined by radioimmunoassay (RIA). Cardiac BNP expression was determined by immunohistochemical staining (IHCS). Omapatrilat and fosinopril significantly decreased MBP from first week to the end of six-month (p