GSK3B and myocardial infarction: While IPostC fails to decrease myocardial infarction in mice in which serine 9 within GSK3β is mutated to alanine (GSK3β-S9A mice) [128], IPC and IPostC effectively reduce infarct size in mice in which serine 9 of GSK3β and serine 21 of GSK3α are rendered to non-phosphorylatable residues [135].