Fig. 3.
The effect of ICBM is concentration-dependent, sensitive to the A3AR antagonist MRS1523, and, differently from Cl-IB-MECA, not reversible after washout. A Pooled data (mean ± SEM) of ICa inhibition in DRG neurons superfused with different concentrations of the irreversible A3AR agonist ICBM (0.01–3 µM), by a maximal concentration (30 nM) of the prototypical A3AR agonist Cl-IB-MECA, by a maximal concentration (1 µM) of ICBM in the presence of the A3AR antagonist MRS1523 (1 µM) or by vehicle (0.1% DMSO). ** P < 0.01; **** P < 0.0001 vs DMSO, one-way ANOVA, Bonferroni post hoc test. B Concentration–response curve of the effect of ICBM on ICa inhibition. EC50 = 22.9 nM (confidence limit 4.1–33.5 nM). C Averaged time-courses of peak ICa amplitude (peak ICa), expressed as % of baseline (bsl) values, measured before, during, or after the application A3AR ligands or their vehicle. D Effect of prolonged washout of Cl-IB-MECA (30 nM) or ICBM (1 µM) on averaged time-courses of peak ICa before, during, and after the application of Cl-IB-MECA (30 nM, purple circles, n = 10) or the new, irreversible, A3AR agonist ICBM (1 µM, green circles, n = 4). P value refers to an unpaired Student’s t-test