The AF vulnerability (including inducibility of AF and AF duration) was significantly increased in Ang II group compared with the control group (inducibility of AF: z = −4.70, P < 0.001; AF duration: z = −4.746, P < 0.001) while the Ang II + apelin group demonstrated reduced AF vulnerability than Ang II group (inducibility of AF: z = −4.40, P < 0.001; total time of AF episodes: z = −4.349, P < 0.001), (Figure 5). The gene discussed is APLN; the disease is atrial fibrillation.