Contribution of bradykinin B2 receptors to the inhibition by valsartan of systemic and renal effects of exogenous angiotensin II in salt-repleted humans.

To investigate whether bradykinin (BK) participates in the inhibition of renal effects of exogenous angiotensin II (AngII) by AngII type 1 receptor (AT1R) blockade, eight salt-repleted volunteers underwent four p -aminohippurate- and inulin-based renal studies of AngII infusion at increasing rates of 0.625, 1.25, and 2.5 ng·kg·min −1 for 30 min. Studies 1 and 2 were preceded by 3 days of placebo, whereas studies 3 and 4 used 240 to 320 mg·day −1 valsartan. Bradykinin B2-type receptor (BKB2R) antagonist icatibant (50 μg·kg −1 ) was coinfused in studies 2 and 4. Mean blood pressure (MBP), glomerular filtration rate (GFR), renal blood flow (RBF), and renal sodium excretion (UNaV) were measured. In study 1, MBP rose by 12.8%, UNaV decreased by 68%, and GFR and RBF also fell ( p p p p