Adenosine-induced accumulation of cAMP is not observed in mouse thymocytes with inactivated A_2AR gene.

Ex vivo thymocytes from wild type mice (A, +/+) or from A_2AR deficient (B,−/−) mice were incubated for 30 minutes with extracellular adenosine in the presence or absence of A_2AR antagonist ZM241385 and cAMP accumulation was measured as described in “Materials and methods.” Insert in panel B demonstrates the typical result of Southern blot DNA screening for +/+, +/−, and −/− A_2AR mice.