Figure 3. APD prolongation and abnormal impulse induction.
A: Application of the K+ channel blocker 4-AP significantly prolonged APD but failed to promote abnormal impulses in WT ventricular myocyte. B: In the presence of the LTCC opener S(−)Bay K8644, automaticity was induced in WT ventricular myocytes at a lowered Gsac level. C: SAC-induced automaticity in the presence of AIP and ISO. D: APD prolongation by 4-AP and ISO, respectively.