Acute antihypertensive effects of the new generation calcium antagonist 3-pyridine carboxylic acid 5-[(cyclopropylamino)-carbonyl]-1,4-dihydro-2,6-dimethyl-4-(2-nitrophen yl) octyl ester on conscious spontaneously hypertensive rats and renal hypertensive rats.

The acute antihypertensive effects of 3-pyridine carboxylic acid 5-[(cyclo-propylamino) carbonyl]-1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl) octyl ester (NP-252, CAS 132031-81-3) administered orally to conscious spontaneously hypertensive rats (SHRs) and renal hypertensive rats (RHRs) were evaluated using the impedance plethysmographical technique as a modified tail cuff method, and compared with those of nifedipine (NF). In the fitness test of this indirect method, the average value of blood pressure (BP) measured in 7 conscious SHRs was 201±6.9 mmHg. This value showed good correlation with that (201±8.8 mmHg) of systolic BP measured by the direct method in the same animals