Objective: To observe the change of neovascular morphology and angiogenesis related factors in the ischemic cerebral area after cerebral infarction and the intervention effect of electroacupuncture (EA).
Methods: Wistar rats were randomly divided into model group(n=90), EA group(n=90), sham operation group(n=90) and control group(n=10). The first three groups were further divided into 1 h, 3 h, 6 h, 9 h, 12 h, 24 h, 3 d, 7 d and 12 d subgroups(n=10 in each subgroup). The cerebral infarction model was established by middle cerebral artery occlusion(MCAO). EA(15 Hz, 2 mA) was applied to "Shuigou"(GV26) for 20 min in the EA group. The 1, 3, 6, 9, 12, 24 h subgroups were treated immediately after modeling, the 3, 7, 12 d subgroups were treated once daily for 3, 7 or 12 days. The neovascular endothelial cells were displayed by immunofluorescence double labeling staining. Quantitive real-time PCR and Western blot were applied to detect the changes of basic fibroblast growth factor (bFGF), angiogenin (Ang) -1, 2, platelet-derived growth factor b (PDGF-b) in ischemic brain tissue, respectively.
Results: After modeling, CD31 and Ki67 positive cells were first observed at 24 h in the model group, and reached the peak at 3 d, decreased at 7 d. While in the EA group, the CD31 and Ki67 positive cells were first observed at 12 h, and reached the peak at 3 d, and gradually decreased until 12 d. Compared with the control group, the mRNA expressions of bFGF at 9 h-12 h, Ang-1 at 12 h-12 d, Ang-2 at 1 h-12 d and PDGF-b at 1 h, 6 h, 9 h, 24 h-12 d were increased in the model group(P<0.01, P<0.05). After EA, the mRNA expressions of bFGF at 24 h-12 d, Ang-1 at 3 d-12 d, Ang-2 at 3 h-24 h and PDGF-b at 3 h, 6 h, 3 d-12 d were increased(P<0.05, P<0.01). In comparison with the control group, the proteins of bFGF at 24 h, Ang-1 at 6 h-12 d, Ang-2 at 1 h-12 d and PDGF-b at 1 h-7 d were increased in the model group(P<0.05, P<0.01). After EA, the proteins of bFGF at 3 d-12 d, Ang-1 at 3 d-12 d, Ang-2 at 3 h-12 h and PDGF-b at 6 h, 3 d-12 d were increased compared with the model group(P<0.05, P<0.01).
Conclusion: EA can up-regulate the expression of angiogenesis-related factors in MCAO rats, which has an important role in the establishment of blood vessel regeneration and collateral circulation, and thus promote the recovery of neurological function.
Keywords: Angiogenesis; Electroacupuncture; Middle cerebral artery occlusion; Shuigou(GV26).