Fig. 2.
Effect of dobutamine on intact papillary muscle contractility. Papillary muscles, isolated from both ACTC E361G (n = 5) and NTG mice (n = 3–5), were stimulated with the addition of 10 μM dobutamine to the perfusion solution at 37°C. Means ± SE of the muscle function measurements (left); percent change with treatment at physiologically relevant frequencies (right) of the following: force production normalized to force produced at 1 Hz (A), time to peak tension (B), time to 90% relaxation (C), dF/dtmin/F (D), and relaxation rate constant (tau; E). Data were analyzed by 2-way ANOVA; *P < 0.05.