FGF21 and atrial fibrillation: Figure 2E represented typical recordings of AF/AT, and our results showed that the vulnerability to electrical-induced AF/AT was markedly increased in AngII mice, which was attenuated by Fgf21 treatment (from 28.5% to 14.6%) (Figure 2F). Additionally, the duration of total AF/AT episodes (sum of AF/AT duration times) was shorter in Fgf21-treated AngII mice as compared with NS-treated AngII mice (Figure 2G).