Figure 1. Concentration-dependent effects of dobutamine on action potential (AP) discharge character in ventricular cardiomyocyte isolated from adult mouse heart.

AP was elicited from the resting membrane potential by a brief pulse with 2 ms duration using current-clamp mode. A. representative image of ventricular cardiomyocyte with recording pipette collected during recording under 40× light microscope; B. and C. representative AP and derivative over the membrane potential before and after 1 μM dobutamine, respectively; D. superimposition of APs recorded in the absence and presence of 0.1 – 1 μM dobutamine.