应用cDNA微阵列分析脊髓损伤后基因表达的差异☆

背景：基因芯片可以大规模地平行检测分析上千个基因的表达模式，克服了传统的一次实验仅能对单个或数个基因表达水平进行分析的局限。目的：应用含有1 176条人类全长基因的cDNA表达谱芯片，对大鼠急性脊髓损伤模型中基因表达水平的变化进行动态观察。方法：雌性SD大鼠70只随机分成正常对照组、手术对照组、损伤4 h，24 h，3 d，7 d，10 d组7组。损伤组切除T7、T8的椎板，并用钢棒从高处自由落下致脊髓损伤。手术对照组仅进行T7、T8椎板切除。正常组和各损伤组于伤后各时间段，手术对照组于术后3 d取T6~T10段脊髓，提取总RNA，运用AtlasImageTM 2.01软件(Clontech)对放射自显影基因表达谱进行分析，各个处理组与正常组相比，灰度值差异超过3倍的基因定为有表达差异。结果与结论：结果显示共有显著表达差异基因81条，其中表达上调的基因有46条，表达下调的基因有35条，并在国内外首次观察到神经激肽B、神经肽Y、垂体后叶加压素V2受体等数个基因在脊髓损伤中的变化。结果表明利用基因芯片技术结合实验动物模型能大规模、高通量地观察急性脊髓损伤继发性损伤的基因表达谱，筛选疾病相关基因，对进一步阐明疾病在基因水平上的发病机制，有重要的意义。

Analysis of gene expression difference following spinal cord injury in rats using complementary DNA microarray

BACKGROUND: Gene microarray can be used to parallel detect expression patterns of large amounts of genes, which overcome the limitation of traditional only single or multiple genes detection. OBJECTIVE: To dynamic observe the changes of gene expression in rat acute spinal cord injury (SCI) models using complementary DNA microarray consisting 1 176 genes.METHODS: Seventy female SD rats were randomly divided into the normal control, surgery control, 4-, 24-hour and 3-, 7-, 10-day injury groups. Rats in the injury groups subjected to T7 and T8 excision, and made SCI models by high falling. Sham animals received only a laminectomy. T6-10 spinal cord was harvested at each time point, and autoradiographic gene expression profile was analyzed by AtlasImageTM 2.01 software (Clontech). Compared with the normal group, greater than 3-fold changes considered as differential expression. RESULTS AND CONCLUSION: We identified 81 genes that showed a greater than 3-fold change in SCI tissues, including 46 genes up regulated and 35 genes down regulated. In addition, changes of neurokinin B, neuropeptide Y and postlobin-v2 receptor gene were firstly found during SCI. The results demonstrated that, gene expression profile during acute SCI can be observed by using gene microarray combined with experimental animal models, which has significance for further pathogenesis study at gene levels.