The present invention provides methods for inducing division of postmitotic mammalian differentiated cardiomyocytes. The invention can be used to repair heart tissue damaged by, for example, myocardial ischemia, hypoxia, stroke, myocardial infarction or chronic ischemic heart disease in vivo. In addition, the methods of the invention can be used to induce heart muscle cells to divide in vitro, in vivo and/or ex vivo, which can then be used in heart tissue repair.
