Fig. 2.
Schematic diagram of the experimental protocol. Mean arterial pressure (MAP) was decreased and increased via intravenous infusion of sodium nitroprusside (NP) and phenylephrine (PE), respectively. Baroreflex response curves were performed under control conditions, following bilateral microinjections into the NTS of selective A2a adenosine receptor agonist CGS-21680 (2.0 and 20 pmol in 50 nl), selective A2a adenosine receptor antagonist ZM-241385 (40 pmol in 100 nl), nonselective A1 + A2a adenosine receptor antagonist 8-SPT (1 nmol in 100 nl), or respective volume control (ACF; 50 and 100 nl for the agonist and the antagonists, respectively), and ∼70 min after the microinjections of the agonist and the antagonists (recovery).