Atrial and brain natriuretic peptides: secretion during exercise in patients with essential hypertension and modulation by acute angiotensin-converting enzyme inhibition.

1. This study examined whether brain and atrial natriuretic peptides (BNP, ANP) are secreted together through the coronary sinus from the heart, and whether plasma concentrations of BNP and ANP were affected by ergometric exercise in patients with essential hypertension. The effects of temocapril, a potent angiotensin-converting enzyme (ACE) inhibitor, on plasma concentrations of these peptides was also examined. 2. The plasma concentrations of immunoreactive (ir) BNP and ir-ANP in the coronary sinus in seven patients with ischaemic heart disease during cardiac catheterization were far greater than values with plasma obtained at the same time from the femoral artery. 3. The plasma concentrations of ir-BNP and ir-ANP increased with exercise and were correlated with each other. Temocapril reduced the blood pressure and slightly (but significantly) decreased the levels of both peptides at rest and during exercise. 4. The results suggest that BNP and ANP were secreted together through the coronary sinus from the heart. The secretion was increased by exercise and suppressed by acute ACE inhibition. The increase in these peptides during exercise may reflect a compensatory mechanism against further elevation of blood pressure.