Adenosine Signaling Modulators in Rodent Studies

All components of the phosphate-buffered saline (PBS) solution (in mM: 3.0 KCl, 10.0 NaH₂PO₄, 2.0 Na₂SO₄, 1.2 MgCl2, 131. 25 NaCl and 1.2 CaCl₂, with pH adjust to 7.4 using concentrated HCl or NaOH) were purchased from Fisher Scientific (Fair Lawn, NJ, USA) and PBS was used for electrode calibration. A 10.0 mM stock solution of adenosine (Fisher Scientific, Fair Lawn, NJ, USA) was prepared in 0.1 M HClO₄ once a month and stored at 4°C. 1.0 μM adenosine solution for electrode calibration was prepared daily in PBS buffer. All drugs were administered intraperitoneally (i.p). Caffeine (100 mg/kg, Sigma Aldrich, St. Louis, MO, USA) was dissolved in 1 mL warm saline. SCH 442416 (3 mg/kg; Tocirs, Bristol, UK) was dissolved in 300 μL dimethyl sulfoxide (DMSO; Amresco, Solon, OH, USA). Doses were selected based on previous experiments in the literature.^{12 (link),59 (link)}