Fig. 2.

Afferent arteriolar responses to ATP alone followed by ATP plus inhibition of P2X₁ receptor (P2X₁R) or the combination of P2X₁R + P2X₇ receptor (P2X₇R) inhibition in kidneys from normotensive rats at baseline pressure. After steady-state diameters were established, ATP (5 µmol/L) was superfused over the blood vessels. A: afferent arteriolar responses to ATP followed by ATP plus P2X₁R inhibitor (P2X₁Ri) and ATP plus P2X₁Ri and P2X₇R inhibitor (P2X₇Ri). B: the order of the inhibitors was changed, and afferent arteriolar responses to ATP and ATP plus P2X₇Ri were measured followed by ATP under P2X₁Ri + P2X₇Ri (n = 4 per group). Data are expressed as means ± SD. *P < 0.05 vs. renal perfusion pressure (RPP) at 100 mmHg; #P < 0.05 vs. RPP at 100 mmHg + ATP; &P < 0.05 vs. RPP at 100 mmHg + ATP + P2X₇Ri.