Fig. 4.

Effect of ANG II type 1 receptor (AT₁R) and P2X₁ (P2X₁R) and P2X₇ receptor (P2X₇R) blockade on afferent arteriolar diameter under high renal perfusion pressure (RPP) in kidneys from hypertensive rats. A: afferent arteriolar responses to increases in RPP from 100 to 140 mmHg were tested followed by P2X₁R inhibitor (P2X₁Ri) and then AT₁R inhibitor (AT₁Ri). B: the order of the inhibitors was reversed. First, afferent arteriolar responses to increases in RPP were followed by AT₁Ri and P2X₁R blockade (P2X₁Ri); then, the combination of P2X₁R plus P2X₇R inhibitor (P2X₁Ri) was tested. Data are expressed as means ± SD; n = 5 per group. *P < 0.05 vs. RPP at 100 mmHg; #P < 0.05 vs. RPP at 140 mmHg; &P < 0.05 vs. RPP at 140 mmHg + AT₁Ri.