Next, we explored the level of cardiac necroptosis in CaCl2‐Ach‐induced AF mice and found protein levels of necroptotic signaling (RIP1, RIP3, CaMKII and MLKL or their phosphorylated forms) (Figure 2A,B), as well as cell membrane translocation of MLKL (Figure 2C,D), were significantly increased. This evidence concerns the gene MLKL and atrial fibrillation.