Alterations of proteins in artificially induced chronic myocardial infarction in rats

We investigated the changes of protein in chronic MI which was occurred with long-term ischemia, without reperfusion. Sprague Dawley (SD) rats were divided into the sham group and the experimental groups (MI groups). The sham group was treated only thoracotomy without ligation for left main descending artery (LMDA) of left coronary artery (LCA), and the experimental groups (M17d, ligation of LMDA for 7 days and MI30d, ligation of LMDA for 30 days) were conducted an artificial chronic MI. The change of proteins according to passage of times was compared and analyzed on first and second dimension (1 and 2D) sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. Among total 46 spots expressed differentially in the sham group versus MI7d and NI30d groups on 2D gel, we selected proteins that the volume of spot was increased in the MI7d and MI30d groups compared with the sham group. After that, the proteins were identified through liquid chromatography/tandem mass spectrometry (LC-MS/MS) analysis. In result, we could obtain many proteins as follows; albumin, glucose regulated protein 58 KDa, similar to tripartite motif protein 50, ubiquinol-cytochrome c reductase core protein II, sarcomeric mitochondrial creatine kinase, ATP synthetase alpha chain (mitochondrial precursor) and creatine kinase. In conclusion, we suggest many changed proteins shown at chromi ischemia after artificial MI and consider that these proteins play an important role in the function of heart after MI.