TABLE 1

Affinities, expressed as K_H, K_L, and K_i values, of selected adenosine receptor agonists and antagonists to A₃ receptors in human lymphocytes Displacement of [³H]MRE 3008F20 binding was determined in the absence and presence of 100 μM GTP. K_H and K_L are the K_i values of the high- and low-affinity states for agonists, respectively. R_H indicates the percentage of A₃ receptors in the high affinity state ± S.E.M.