A2Aadenosine receptor-mediated inhibition of renal injury and neutrophil adhesion

Abstract
We sought to determine the mechanisms responsible for the reduced renal tissue injury by agonists of A2A adenosine receptors (A2A-ARs) in models of ischemia-reperfusion (I/R) injury. DWH-146e, a selective A2A-AR agonist, was administered subcutaneously to Sprague-Dawley rats and C57BL/6 mice via osmotic minipumps, and animals were subjected to I/R. I/R led to an increase in plasma creatinine and kidney neutrophil infiltration. Infusion of DWH-146e at 10 ng · kg−1 · min−1 produced a 70% reduction in plasma creatinine as well as a decrease in neutrophil density in outer medulla and cortex and myeloperoxidase activity in the reperfused kidney. Myeloperoxidase activity in kidney correlated with the degree of renal injury. P-selectin and intercellular adhesion molecule 1 (ICAM-1) immunoreactivity were most prominent in endothelial cells of peritubular capillaries and interlobular arteries of cortex and outer and inner medulla of vehicle-treated mice whose kidneys were subjected to I/R. DWH-146e treatment led to a pronounced decrease in P-selectin- and ICAM-1-like immunoreactivity. These data are consistent with our hypothesis that A2A-AR agonists limit I/R injury due to an inhibitory effect on neutrophil adhesion.