Plasma brain natriuretic peptide and endopeptidase 24.11 inhibition in hypertension.

In contrast to the wealth of information available concerning the response of plasma atrial natriuretic peptide to changes in pressure and volume status and to inhibition of endopeptidase 24.11, very little is known of possible concomitant effects on brain natriuretic peptide. The effects of change in posture, pressor infusions of angiotensin II, or inhibition of endopeptidase 24.11 were documented in two groups of patients with essential hypertension receiving one of two orally active inhibitors (SCH 42495 or UK 79300) in double-blind, placebo-controlled, random-order crossover studies. Sustained (4 days) inhibition of endopeptidase 24.11 with either inhibitor significantly enhanced plasma atrial natriuretic peptide (P < .05, both groups) but suppressed plasma brain natriuretic peptide (P < .01, both groups) in association with significant falls in arterial pressure (P < .05, both groups). Assumption of the recumbent posture increased plasma atrial natriuretic peptide (20 +/- 5 vs 13 +/- 3 pmol/L, P < .05), whereas brain natriuretic peptide was unchanged (7 +/- 0.3 vs 7 +/- 0.4 pmol/L, NS). Pressor infusions of angiotensin II increased plasma levels of both atrial natriuretic peptide and brain natriuretic peptide (33 +/- 11 vs 17 +/- 4 pmol/L, P < .05, and 7.5 +/- 0.6 vs 5.5 +/- 0.4 pmol/L, P < .05, respectively). In contrast to atrial natriuretic peptide, brain natriuretic peptide probably is primarily regulated by left ventricular load rather than by atrial distending pressure.(ABSTRACT TRUNCATED AT 250 WORDS)