Hemodynamic effects of [Sar1, Ile8] AII, an angiotensin II analog, in the renin subgroups of essential hypertension.

Hemodynamic effects of [Sar1, Ile8] AII, an angiotensin II analog, were studied in 30 patients with essential hypertension, who were subdivided into 11 low renin, 10 normal renin and 9 high renin groups according to low, normal and high PRA values both before and after furosemide administration (80 mg, orally) plus 4 h of ambulation, respectively. [Sar1, Ile8] AII infusion (600 ng/kg/min) produced significant increases in mean blood pressure (MBP) and total peripheral resistance index (TPRI) in normal renin and low renin groups and significant decreases in MBP and TPRI in high renin group, while the cardiac index and heart rate remained unchanged during the infusion in these three groups. Change in MBP at 30 min of [Sar1, Ile8] AII infusion correlated significantly with alteration in TPRI in 23 patients with essential hypertension, who completed the 30-min infusion. The response of both MBP and TPRI to [SAR1, Ile8] AII also correlated significantly with basal PRA. These results suggest that blood pressure response to [SAR1, Ile8] AII in essential hypertension is primarily due to alteration in total peripheral resistance and that direction and amplitude of the response of both MBP and TPRI are practically dependent on basal PRA levels.