Fig. 2.

Pial arteriolar responses to the suffusion of 1, 10, and 100 μM ATP in the absence and presence of the ecto-5′-nucleotidase inhibitor α,β-methylene adenosine 5′-diphosphate (AOPCP; 300 μM; A), the A₂ receptor blocker ZM 241385 (10 μM; B), the P2Y₁ receptor blocker MRS 2179 (10 μM) and MRS 2179 plus the A₂ antagonist ZM 241385 (10 μM; C), and the ecto-diphosphohydrolase blocker ARL-67156 (100 μM; E). In D, the dose-related responses to ADP, in the presence or absence of ZM 241385 and ZM 241385 plus MRS 2179, are also shown. Pial arteriolar responses are expressed as the percent change from the baseline diameter value. Values are means ± SD. *P < 0.05 vs. initial; †P < 0.05 vs. AOPCP; n = 5 per group.