Table 2 .

Inhibition of A₃AR binding of known AR agonists and antagonists using MRS5218 (30 nM) as a FCM tracer in whole cells.^a

Compound	hA3AR radioligand binding, Ki (nM)b	FCM binding at hA3AR, Ki(nM)
Agonists
Cl-IB-MECA	1.4	1.3±0.3
IB-MECA	1.8	2.7±0.4
NECA	25	73.6±7.9
CPA	72	88.4±13.6
Antagonists
MRS1220	0.65	5.9±0.7
XAC	13.8	17.6±3.6

^aIncubation of A₃AR-expressing CHO cells with MRS5218 (30 nM) for 60 min at 37 °C was performed in the presence of 0.4 M sucrose (60 min). The inhibitors were added 15 min prior to the fluorescent tracer. K_i values represent the mean of at least three replicates.

^bK_i values for A₃AR binding affinity in cell membrane preparations using [¹²⁵I]I-AB-MECA are reported [16 and references therein].