The cardiovascular effects of dipotassium (Z)-2-[[5-ethyl-3-[2'-(1H-tetrazol-5-yl)
biphenyl-4-yl] methyl-1,3,4-thiadiazoline-2-ylidene]aminocarbonyl]-1-cyc lopentencarboxylate CAS 169328-25-0,
KRH-594), a new
angiotensin II type 1 (AT1) receptor antagonist, on pressure-overload
cardiac hypertrophy in rats and on acute left ventricular failure in dogs were investigated. In rats with a 2-week abdominal aorta constriction, left ventricular weight (LVW) and systolic blood pressure (SBP) were significantly greater than in
sham-operated rats.
Oral administration of
KRH-594 (10 or 30 mg/kg/day for 2 weeks) reduced the increases in both LVW and SBP. Another AT1 receptor antagonist,
candesartan cilexetil (1 or 3 mg/kg/day for 2 weeks), also prevented this type of
cardiac hypertrophy. In anesthetized dogs with a 60-min coronary
ligation, left ventricular end-diastolic pressure (LVEDP) and total peripheral resistance (TPR) were raised, whereas the maximum first derivative of left ventricular pressure and cardiac output were both decreased.
Intravenous administration of
KRH-594 (3 mg/kg) significantly attenuated the increases in both LVEDP and TPR after coronary
ligation. These results suggest that
KRH-594, by reducing the cardiac afterload, may ameliorate pressure-overload
cardiac hypertrophy in rats and produce an improvement in the hemodynamic status of dogs with acute left ventricular failure.