The main function of Gap19 is to regulate the domain of the Cx43 CL pH receptor and block the Cx43 semi-channel.[28] In the myocardial ischemia-reperfusion model, Gap19 has been shown to decrease the expression of Cx43 in mitochondria, thereby reducing the size of myocardial infarction. This evidence concerns the gene GJA1 and myocardial infarction.