In addition, studies have demonstrated that ASIC3 can increase the tolerance of NP and AF cells to acidic microenvironment by increasing the expression of nerve growth factor (NGF), while ASIC1 is able to promote the apoptosis of CEP by mediating the influx of intracellular Ca2+ (Uchiyama et al., 2007; Li et al., 2014). This evidence concerns the gene NGF and atrial fibrillation.