大鼠急性脊髓损伤后血小板衍化生长因子-B的表达

Expression of Platelet Derived Growth Factor-B after Acute Spinal Cord Injury in Rats

目的:探讨血小板衍化生长因子-B(PDGF-B)在脊髓损伤(SCI)后对脊髓功能恢复的作用。方法:健康雌性SD大鼠48只随机分为免疫组化组(30只)和反转录-聚合酶链反应(RT-PCR)组(18只)。麻醉后,用改制的Ⅱ型纽约大学装置建立大鼠脊髓急性损伤模型。用免疫组化检测急性SCI后不同时段PDGF-B在脊髓中的表达,用RT-PCR检测PDGF-B的mRNA在急性SCI后不同时段表达的变化。结果:①PDGF-B蛋白表达:急性SCI后24 h,PDGF-B在损伤区周围神经元的表达开始增加(5.92±3.23),并于7 d后维持在一定水平,14 d后PDGF-B阳性细胞数增多,28 d达高峰(85.00±13.49),主要表达于坏死区增生的神经胶质细胞。②PDGF-B mRNA表达:SCI后1 d,PDGF-B mRNA表达降低,3 d接近正常,随后略有下降,14 d后mRNA表达升高,28 d基本回到正常。结论:急性SCI后,PDGF-B对损伤脊髓的功能恢复有重要作用。

Objective： To explore the role of platelet derived growth factor-B（PDGF-B）on spinal cord functional recovery after acute spinal cord injury（SCI）in rats. Methods： Forty-eight health SD female rats were randomly assigned into immunohistochemistry group（ n =30）, RT-PCR group（ n =18）. After anesthesia, the rat model with acute SCI was established using the modified weight-drop device from New York University. Immunohistochemistry method was used to detect the expression of PDGF-B protein after SCI, and RT-PCR was used to monitor the changes of PDGF-B mRNA. Results： After SCI, the expression of PDGF-B was different from that of control group. One day later, the numbers of PDGF-B positive cells and the PDGF-B mRNA were showed to increase tendentiously. Until 28 days, the numbers of PDGF-B positive cells reached ,the peak because of proliferative gligcyte. Conclusion： After SCI, PDGF-B plays an important role in spinal cord functional recovery after SCI.