Figure 2.

Effects of 30-fold β₂AR overexpression on left ventricular function in Gαq overexpressing transgenic mice. (A) Echocardiographic left ventricular shortening is depressed in Gαq overexpressors compared with nontransgenic controls (NTG). In Gαq/β₂AR_L mice, fractional shortening is normalized (n = 6–11). (B) Left ventricular +dP/dt_max at intrinsic heart rates (solid bars) and matched atrial paced heart rates (450 beats per min) (hatched bars) is depressed in Gαq overexpressors and normalized in the Gαq/β₂AR_L mice under both conditions (n = 3–5). ∗, P < 0.02 vs. NTG.