Fig. 5
Carbenoxolone changed the spatial distribution of optical action potential parameter values and induced pacemaker shifts. Representative pseudocolor images of the control (a) and those after the application of carbenoxolone (b) are shown. The open circles and open triangles indicate the leading pacemaker site and the site of maximum phase-4 slope, respectively. c Optical membrane potential trajectories of the region of leading pacemaker site (open circles) and the region of maximum phase-4 slope (open triangles) in a and b. SVC Superior vena cava, SEP internal septum, RA right atrium