Effect of electroacupuncture on expression of stromal cell derived factor-1α in focal ischemic cerebral tissue of rats with cerebral ischemia/ reperfusion injury / 针刺研究

ABSTRACT

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Baihui" (GV20) and "Zusanli" (ST36) on the expression of stromal cell derived factor-1α (SDF-1α) and CD34 in ischemic cortex tissue of cerebral ische-mia /reperfusion injury (CI/RI) rats, so as to study its mechanisms underlying improving CI/RI. METHODS: Thirty male SD rats were equally and randomly divided into sham operation, model and EA groups (n=10 rats in each group). The CI/RI model was established by occlusion of the middle cerebral artery for 120 min, followed by reperfusion. EA (40 Hz, 1-2 mA) was applied to GV20 and left ST36 for 20 min, once daily for successive 14 days. The neurological deficit severity was assessed by using Longa's and colleagues' methods. The histopathological changes of the ischemic tissues were observed after H.E. staining and the expression of SDF-1α and CD34 in the ischemic cortex tissues was detected by immunohistochemistry. RESULTS: After modeling, the neurological deficit score, and the numbers of SDF-1α and CD34-positive cells in the ischemic cerebral cortex tissue were significantly increased in the model group (P<0.05). Following EA intervention, the increased neurological deficit score was reversed at the 3rd, 7th and 14th day, and the increased SDF-1α and CD34-positive cells were significantly further up-regulated in the EA group (P<0.05). H.E. staining showed tissue edema, widening of the intercellular space, cavitation-like changes, neuronal shrinkage, nuclear pyknosis with hyperchroma or even disappearance, and aggregation of inflammatory and neurogliocytes in the model group. These situations were relatively milder in the EA group. CONCLUSION: EA of GV20 and ST36 can improve neurological function of CI/RI rats, which may be associated with its effect in up-regulating the expression of SDF-1α and CD34 proteins in the ischemic cerebral cortex tissues.