Contractile response induced by 2-MeS-ADP (100 μM) in aortas from vehicle-treated control (white bars, n = 5) and vehicle-treated Ang II-hypertensive rats (black bars, n = 6) incubated with L-NAME (100 μM) and indomethacin (10 μM) for 30 minutes, to rule out the interference from endogenous release of NO and cyclooxygenase products, respectively. Experiments were conducted in the presence (+) or absence (−) of MRS-2179 (0.1 μM), a P2Y1 receptor antagonist, MRS-2395 (0.1 μM), a P2Y12 receptor antagonist and MRS-2211 (1 μM), a P2Y13 receptor antagonist. Results are presented as mean ± SEM in each experimental group. *P<0.05 vs. respective vehicle-treated control rats. † P<0.05 vs. vehicle-treated Ang II rats.