Elevated expression of C3G protein in the peri-infarct myocardium of rats

BACKGROUND The integrin β1 subunit and its downstream molecules such as integrin-linked kinase (ILK) and focal adhesion kinase (FAK) are indispensable to the inhibition of postinfarction cardiac remodeling, ischemic cardiomyopathy, and heart failure. As a component of the integrin pathway, C3G (Crk SH3-domain-binding guanine nucleotide exchange factor) protein may also participate in postinfarction cardiac remodeling, ischemic cardiomyopathy, and heart failure. MATERIAL/METHODS Experimental myocardial infarction (MI) and sham-operation (sham) models were set up in Sprague-Dawley rats. C3G protein expression in the myocardium in the sham group and in the non-infarcted myocardium of the peri-infarct zones in the MI group was examined by Western blot. RESULTS The C3G protein expression in the myocardium was 0.22±0.06, n=8 in the post-sham 24-hour group; 0.29±0.10, n=8 in the post-MI 24-hour group; 0.22±0.07, n=8 in the post-sham 12-week group; and 0.56±0.14, n=8 in the post-MI 12-week group. The C3G protein expression in the myocardium in the post-MI 12-week group was significantly elevated compared to that in the post-sham 12-week group (p=0.0002), in the post-sham 24-hour group (p=0.0002), and in the post-MI 24-hour group (p=0.0006). CONCLUSIONS C3G protein expression exhibits in the myocardium of rats. Furthermore, C3G protein expression is significantly elevated in the non-infarcted myocardium of the peri-infarct zones. The elevated C3G protein expression could participate in postinfarction cardiac remodeling, ischemic cardiomyopathy, and heart failure.