Molecular biological study on ischemic cerebral injury.

缺血性细胞损伤的机制仍然是一个有争议的问题。利用Atlas cDNA表达阵列，研究了蒙古沙鼠前脑缺血5分钟后海马mRNA表达谱的变化。在戊巴比妥麻醉下，分别于缺血后6小时（n=5）和2天（n=5）处死沙鼠，并于术后6小时处死假手术沙鼠（n=5）。从各组海马样品中分离Poly A^+ RNA。第一步是使用试剂和[α-^<32>P]dATP对每个RNA群体进行1 μg的逆转录。将放射性标记的复杂cDNA探针与Atlas阵列单独杂交过夜。将Atlas阵列暴露在FUJI生物成像分析仪的成像板上。对照组在588个cDNA点中，放射自显影显示72个杂交信号。mRNA表达变化可分为3种模式；减少或消失（29个mrna），减少或恢复（11个mrna），增加（32个mrna）或新出现（38个mrna）。新出现的mrna与细胞间通讯、蛋白转换、应激反应蛋白和生长因子有关。研究短暂性前脑缺血后mRNA表达谱的改变是重要的。

The mechanisms of ischemic cell damage are still a matter of debate. Using Atlas cDNA expression arrays, we examined changes of mRNA expression profile in the hippocampus following 5-minute-forebrain ischemia in Mongolian gerbils. Under pentobarbital anesthesia, gerbils were sacrificed by decapitation at 6 hours (n=5) and 2 days (n=5) after ischemia, and sham-operated gerbils (n=5) were sacrificed at 6 hours after surgery. Poly A^+ RNA was isolated from the hippocampal samples in each group. The first step was to reverse transcribe 1 μg of each RNA population using the reagents and [α-^<32>P]dATP.The radioactively labeled, complex cDNA probes were separately hybridized overnight to the Atlas arrays. The Atlas arrays were exposed to the imaging plate of the FUJI bioimaging analyzer. Autoradiography in the control group showed 72 hybridization signals out of 588 cDNA dots. The changes in mRNA expression were classified into 3 patterns ; decrease or disappearance (29 mRNAs), decrease and recovery (11 mRNAs), and increase (32 mRNAs) or new appearance (38 mRNAs). New appearance mRNAs were related to cell-cell communication, protein turn over, stress response protein, and growth factors. It is important to investigate altered mRNA expression profiles following transient forebrain ischemia.