Renin inhibitors: their use in understanding the role of angiotensin II as a pressor hormone.

Infusion of H.261, the inhibitor of human renin in the baboon, lowered blood angiotensin I, plasma angiotensin II, and arterial pressure suggesting that in the sodium-depleted state angiotensin II contributes to the maintenance of arterial pressure. In a second experiment dose-response infusions of angiotensin II were given in conscious sodium-depleted dogs before and during infusion of the renin inhibitor H.77. These suggested that the contribution of angiotensin II to the maintenance of arterial pressure in this state was made mainly by a circulating peptide. Preliminary results in normal humans show that infusion of H.142 intravenously lowered angiotensin I, angiotensin II, and arterial pressure.