Study on the Effect of Electroacupuncture on Apoptosis and Nerve Growth Factor of Cerebral Tissues in Rats with Focal Brain Ischemia

Objective: To observe the effect of electroacupuncture (EA) of Dazhui(GV 14) and Baihui(GV 20) on apoptosis and nerve growth factor (NGF) expression in rats with cerebral ischemia. Methods: 24 Wistar rats were randomly and evenly divided into sham-operation group, ischemia group and EA+ischemia group. Local brain ischemia was produced by occlusion of the middle cerebral artery (MCAo). Dazhui(GV 14) and Baihui(GV 20) were punctured with filiform needles and stimulated electrically with an EA therapeutic apparatus (5～10 Hz, dense-sparse waves, 3～5 V and stimulating duration of 30 min). The rat's cerebral tissues of various groups were cut into sections to be stained with immunohistochemical method. The TUNEL method was used to display apoptosis state and S-P method employed to show NGF expression. Results: TUNEL staining showed that the number of the died neurocytes in sham-operation group, ischemia group and ischemia+EA group were 0, 676±12 and 326±15 respectively, suggesting that EA could evidently suppress apoptosis of the ischemic cerebral tissues. S-P staining method showed that the number of NGF receptor immunoreaction positive cells of sham-operation group, ischemia group and ischemia+EA group were 2.0±0.3, 6.0±0.3 and 35.0±2.0 separately. In addition, the density of the immunoreaction positive cell staining was also higher in EA+ischemia group. It suggested that EA could remarkably potentiate NGFR expression in the ischemic cerebral tissues (P0.01). Conclusion: EA can relieve apoptosis of the ischemic cerebral tissues and strengthen NGF expression, suggesting that EA has a certain protective action on ischemic cerebral injury through up-regulation of the expression of NGF.