Anesthetized rats were pretreated intravenously with either vehicle [A; Control Group], 10 mg/kg of ZM 241385 (B; A2A Antagonist Group), 30 mg/kg of PSB 1115 (C; A2B Antagonist Group) or ZM 241385 plus PSB 1115 (D; A2A + A2B Antagonist Group), and 15 min later MBF was averaged over 30 min (Basal). Next, rats received an IV injection of 8-aminoguanine (33.5 μmoles/kg), and after approximately 1 hr MBF was averaged over 30 min (8-Aminoguanine). P-values are from paired t-tests. Values are means and SEMs for the indicated sample size (n).