The extracellular adenosine-triggered cAMP accumulation in mouse lymphoma cells correlates with expression of A2a receptors. (A) Mouse lymphoma cells SJL but not NFS1135 cells express A2a receptor mRNA. The isolation of mRNA and Northern blot studies were performed as described in the Materials and Methods. (B) The A2a receptor expressing SJL cells but not A2a receptor-negative NFS1135 cells accumulate cAMP after incubation with different concentrations of adenosine or adenosine analogs NECA, 2CADO, and CGS21680.