βAR signaling to AC in cardiac membrane from nontransgenic, Gαq-transgenic, and dual-transgenic Gαq/β2ARM mice. Overexpression of β2AR to ≈140-fold in the Gαq mice resulted in enhanced basal and isoproterenol stimulated activities. Maximal activities were not different than NTG (P = 0.61), while the basal activities trended toward being lower, but not statistically different (P = 0.08), than NTG. Shown are mean results from experiments performed with four mice from each group.