AVE 0991, a nonpeptide mimic of the effects of angiotensin-(1-7) on the endothelium

Recently, we demonstrated that the heptapeptide angiotensin-(1-7) (Ang-[1-7]) exhibits a favorable kinetic of nitric oxide (NO) release accompanied by extremely low superoxide (02) production. In this report we describe AVE 0991, a novel nonpeptide compound that evoked effects similar to Ang-(1-7) on the endothelium. AVE 0991 and unlabeled Ang-(1-7) competed for high-affinity binding of [I-125]-Ang-(1-7) to bovine aortic endothelial cell membranes with IC50 values of 21 +/- 35 and 220 +/- 280 nmol/L, respectively. Stimulated NO and O-2(-) release from bovine aortic endothelial cells was directly and simultaneously measured on the cell surface by selective electrochemical nanosensors. Peak concentrations of NO and O-2(-) release by AVE 0991 and Ang-(1-7) (both 10 mumol/L) were not significantly different (NO: 295 +/- 20 and 270 +/- 25 nmol/L; O-2(-): 18 +/- 2 and 20 - 4 nmol/L). However, the released amount of bioactive NO was approximate to5 times higher for AVE 0991 in comparison to Ang-(1-7). The selective Ang-(1-7) antagonist [D-Ala(7)]-Ang-(1-7) inhibited the AVE 0991-induced NO and O-2(-) production by approximate to50%. A similar inhibition level was observed for the Ang II AT(1) receptor antagonist EXP 3174. In contrast, the Ang II AT(2) receptor antagonist PD 123,177 inhibited the AVE 0991-stimulated NO production by approximate to90% but without any inhibitory effect on O-2(-) production. Both NO and O-2(-) production were inhibited by NO synthase inhibition (approximate to70%) and by bradykinin B-2 receptor blockade (approximate to80%). AVE 0991 efficiently mimics the effects of Ang-(1-7) on the endothelium, most probably through stimulation of a specific, endothelial Ang-(1-7)-sensitive binding site causing kinin-mediated activation of endothelial NO synthase.