Coronary artery ligation increased the plasma level of myocardial enzymes and damaged myocardial tissue.

<p>(A) The plasma level of the myocardial enzymes LDH-L, CK and CK-MB (U/L) in naïve rats and rats with sham operation and CMI surgery. ***, <i>p</i> < 0.001 compared with the naïve and sham groups. (B-D) HE staining showing the myocardial tissue of the left ventricle in naïve rats (B), rats with the sham operation (C) and rats with CMI surgery (D). LDH-L, L-lactate dehydrogenase; CK, creatine kinase; CK-MB, creatine kinase MB isoenzyme; CMI, chronic myocardial infarction. Scale bar: 50 μm in (B-D).