脑卒中大鼠后室下区祖细胞和神经发生减少的神经影像研究

目的:通过神经影像学研究脑卒中大鼠后室下区祖细胞和神经发生减少的变化情况。方法:2个月龄的Wistar雄性大鼠70只随机分为2组:脑卒中大鼠模型组(n=35)和正常组(n=35)。构建脑卒中大鼠模型后通过磁共振成像系统观察大鼠祖细胞归巢情况、脑梗塞面积与对侧脑组织体积的百分比和脑白质纤维束重塑情况;采取免疫化组织方法分析大鼠血管新生和神经发生情况;利用Western Blot法分析脑组织内细胞因子及炎症因子的表达;再根据RT-PCR方法计算Neu N蛋白和GFAP蛋白表达。结果:MRI扫描于T1WI及T2WI序列下,通过所得图像及信号可知,模型组大鼠祖细胞归巢信号变化、脑梗塞面积与对侧脑组织体积的百分比和脑白质纤维束重塑情况比较间有显著差异(P<0.05),具有统计学意义。脑卒中大鼠血管新生和神经发生、细胞因子EVGF和BDNF水平、Neu N蛋白和GFAP蛋白表达均较正常大鼠低(P<0.05),而炎症因子IL-1β和TNF-α水平则相对较高(P<0.05)。结论:神经影像可用于脑卒中大鼠后室下区祖细胞和神经发生下降的研究,结合组织学分析,进一步验证了结果的可行性与有效性。

Neuroimaging Study of Progenitor Cells and Neurogenesis Reduction in the Posterior Inferior Compartment of Stroke Rats

Objective: To study the changes of progenitor cells and neurogenesis in the posterior subventricular zone of stroke rats through neuroimaging. Methods: Seventy 2-month-old male Wistar rats were randomly divided into two groups: model group(n=35) and normal group(n=35). The homing of progenitor cells, the percentage of infarct size and contralateral brain tissue volume, and the remodeling of white matter fiber tracts were observed by MRI system;The angiogenesis and neurogenesis were analyzed by immunohistochemistry;Western blot was used to analyze the expression of cytokines and inflammatory factors in brain tissue;The expression of neu N protein and GFAP protein were calculated by RT-PCR. Results: MRI scanning on T1 WI and T2 WI showed that the changes of homing signal, percentage of cerebral infarct area and contralateral brain tissue volume, and the remodeling of white matter fiber tracts in the model group were significantly different(P<0.05), with statistical significance. The levels of angiogenesis and neurogenesis, cytokines EVGF and BDNF, Neu N protein and GFAP protein in stroke rats were lower than those in normal rats(P<0.05),while the levels of inflammatory cytokines IL-1β and TNF-α were higher(P<0.05). Conclusion: Neuroimaging can be used to study progenitor cells and neurogenesis decline in the hypoventricular posterior region of stroke rats, and combined with histological analysis,the feasibility and effectiveness of the results are further verified.