Effects of an angiotensin II receptor antagonist, TCV-116, on renal haemodynamics in essential hypertension.

ABSTRACT

The renal effects of a nonpeptide angiotensin II receptor antagonist, TCV-116, were investigated in 12 hospitalised patients with mild-to-moderate essential hypertension. After a 2-week placebo period, TCV-116 was given for 2 weeks in increasing doses from 4 mg to 8 mg daily to normalise the mean blood pressure. Blood pressure fell from 156 +/- 9/93 +/- 3 mmHg at the end of the placebo period to 140 +/- 9/85 +/- 4 mmHg after TCV-116 treatment. The pulse rate was unchanged. Renal vascular resistance fell from 1.62 +/- 0.20 to 1.37 +/- 0.17 dyne.s.cm-5 . 1.48 m2 x 10(4), renal plasma flow increased from 329 +/- 19 to 367 +/- 27 mL.min-1.1.48 m-2, and GFR was unchanged despite a fall in renal perfusion pressure. TCV-116 reduced the filtration fraction from 0.302 +/- 0.019 to 0.258 +/- 0.009, suggesting a preferential reduction in efferent arteriolar resistance. The fractional excretion of sodium, potassium, and urate did not change. An increase in plasma renin activity (from 1.1 +/- 0.3 to 2.2 +/- 0.7 ng.mL-1.h-1) and a fall in the plasma aldosterone concentration (from 6.2 +/- 0.8 to 4.5 +/- 0.7 ng.dL-1) were also seen. These results indicate that TCV-116 has favourable renal effects and a concomitant hypotensive action in patients with mild-to-moderate essential hypertension.