脑缺血诱发星形胶质细胞粒细胞集落刺激因子受体和胶质细胞源性神经营养因子的表达

目的 探讨粒细胞集落刺激因子(G-CSF)在缺血脑保护中的作用机制.方法 制作大鼠大脑中动脉栓塞模型,7 d后断头取脑做冰冻切片,用免疫荧光双标的方法观察缺血周边区与假手术组相同部位G-CSF受体、胶质细胞源性神经营养因子(GDNF)和微管相关蛋白2(MAP2)、神经胶质原酸性蛋白(GFAP)的共表达情况.结果 G-CSF受体和GDNF在正常大鼠脑内广泛表达于神经元,不表达于星形胶质细胞;但在缺血周边区,星形胶质细胞亦部分表达G-CSF受体和GDNF.在正常脑组织,大部分G-CSF受体阳性的细胞也表达GDNF.结论 脑缺血可诱导缺血周边区星形胶质细胞表达G-CSF受体和GDNF,推测缺血后的内源性神经保护作用可能与缺血周边区星形胶质细胞的G-CSF受体表达以及GDNF产生有关.

Cerebral ischemia induces astrocytes to express granulocyte colony stimulating factor and glial cell fine-derived neurotrophic factor

Objective To explore the neuroprotective mechanisms of granulocyte colony stimulating factor (G-CSF) in ischemic brain injury. Methods Brain tissues were taken out from MCAO and sham operated Sprague-Dawley rats 7 days after operation. The expression of G-CSFR, GDNF, MAP2 and GFAP was measured by using immunofluorescence co-staining. Results The expression of G-CSFR and GDNF were widely distributed in the neurons in normal brain tissues, not in the astrocytes. However, in ischemic peripheral zone, part of G-CSFR and GDNF positive cells merged with GFAP positive cells, in normal brain tissues, most G-CSFR positive cells were co-expressed with GDNF. Conclusion Cerebral ischemia induces astrocytes to express G-CSFR and GDNF, suggesting that endogenous neuroprotection by cerebral ischemia may be related with the expression and production of G-CSFR and GDNF in astrocytes in ischemic peripheral zone.