Mice with targeted disruption of eNOS had a higher incidence of arrhythmias induced by ouabain (Rakhit et al., 2001) or β-adrenergic stimulation (Wang et al., 2008), confirming earlier work reporting on the protective effects of NO against ventricular arrhythmias in dogs (Vegh et al., 1992). Here, NOS3 is linked to Arrhythmia.