Figure 1. β-adrenergic receptor protein levels in control, β2-adrenergic receptor knockout mice+49b, and β2-adrenergic receptor knockout mice. A: Compound 49b significantly increased β1-adrenergic receptor levels compared to untreated β2-adrenegic receptor knockout (KO) mice. B: β2-adrenergic receptor protein levels are minimally restored in β2-adrenergic receptor KO mice treated with Compound 49b. *p<0.05 versus wild-type (WT); #p<0.05 versus β2-adrenergic receptor KO mice. n = 5 for all groups. Data are mean ± standard error of the mean (SEM).