Figure 3.

The ISO response in BE(2)-C cells is mediated through β₂-ARs. Cells were assayed for ISO-stimulated accumulation of cAMP in the presence and absence of three different β-AR antagonists. The non-selective antagonist propranolol and the β₂-selective antagonist ICI 118,551 antagonized the stimulatory effect of ISO (100 nM), while the β₁-selective antagonist CGP 20712A was without effect (^*P<0.05, ^**P<0.01, ^***P<0.001 by ANOVA; n=3–13). Antagonists alone had no effect on basal cAMP levels at these concentrations (data not shown).