GJA1 and myocardial ischemia: A recent study on myocardial ischemia–reperfusion injury causing arrhythmia [123] has tested in isolated-perfused rat heart and in Cx43-expressing H9c2 cultured cardiac cells, the effect of a peptide called SP15, which mimics the CaM-binding site of a Cx43’s cytoplasmic loop sequence known to bind CaM, in an attempt to restore gap junction function for mitigating reperfusion arrhythmias.