ABSTRACT
BACKGROUND: Studies have shown that bone marrow mesenchymal stem cell (BMSC) transplantation can effectively improve cardiac function after myocardial infarction. However, few reports have been issued on myocardial electrophysiology after BMSCs transplantation. OBJECTIVE: To observe the effects of BMSCs transplantation on voltage-gated K+channel protein and myocardial infarction-related cytokines, thereby providing basic evidence for further exploration on the mechanism underlying arrhythmia in myocardial infarction due to BMSCs transplantation. METHODS: Forty male Wistar rats, SPF grade, were randomly divided into four groups: sham group, model group, cell culture medium group and BMSCs group. The myocardial infarction model was created in rats by permanent ligation of the left descending coronary artery. At 15-20 minutes after surgery, BMSCs (100 μL, 1×106) or cell culture medium (100 μL) was injected at four sites in the peri-infarct zone. Four weeks after cell therapy, cardiac samples were taken, the pathological morphology of the infarcted myocardium was observed by hematoxylin-eosin staining, and the infarct size was calculated; the expression levels of voltage-gated K+channel proteins Kv1.2 and Kv1.5 and cardiac troponin T (cTnT) were measured by western blot assay; and the expression levels of apoptotic factor (Caspase-3), autophagy factor (Bcl-2), nitric oxide and superoxide dismutase were tested by immunohistochemistry. RESULTS AND CONCLUSION: Compared with the model group and cell culture medium group, the infarct size decreased in the BMSCs group (P < 0.05); the expression levels of cTnT, Kv1.5 and superoxide dismutase increased (P < 0.05), and the expression levels of Caspase-3, Bcl-2 and Kv1.2 decreased (P < 0.05) in the BMSCs group. In summary, BMSCs transplantation can promote the expression of voltage-gated K+channel proteins, and improve anti-oxidation capacity of the myocardium and decrease apoptosis and autophagy.