Ahmed Farid, Brown Kevin M, Stephan Dietrich A, Morrison John C, Johnson Elaine C, Tomarev Stanislav I
Laboratory of Molecular and Developmental Biology, National Eye Institute, Bethesda, Maryland 20814-9692, USA.
Invest Ophthalmol Vis Sci. 2004 Apr;45(4):1247-58. doi: 10.1167/iovs.03-1123.
The goal of this study was to identify altered patterns of retinal mRNA expression after experimental elevation of intraocular pressure (IOP) in a rat glaucoma model.
Brown Norway rats (N = 16) received unilateral episcleral vein injection of hypertonic saline to elevate IOP. IOP was monitored daily by handheld tonometer, and retinas were collected 8 days and 5 weeks after surgery. Comparison of mRNA levels between experimental and fellow retinas was made using gene microarrays (rat U34A rat arrays; Affymetrix, Santa Clara, CA). Semiquantitative RT-PCR was used to confirm selected results from array analysis and to compare with alterations after optic nerve transection.
IOP elevation for 5 weeks resulted in reproducible changes in levels of 81 mRNAs. Of these, 74 increased, whereas only 7 decreased. The expression levels of 27 of these same messages were changed after 8 days of IOP elevation. In addition, four other genes demonstrated altered expression after the shorter period of elevated IOP exposure. Approximately half of the mRNAs with altered expression were associated with either neuroinflammatory responses or apoptosis. For 25 of the selected functionally relevant messages altered by array analysis, the alterations were confirmed by semiquantitative RT-PCR. The levels of 24 of 25 selected messages were also changed after optic nerve transection.
The activation of glia and the complement system after IOP elevation, which is similar to that described in several neurodegenerative diseases and after optic nerve transection, suggests that this rat glaucoma model could be used to evaluate the neuroprotective potential of therapeutic agents that target these processes.
本研究的目的是在大鼠青光眼模型中，确定实验性眼压升高后视网膜mRNA表达的改变模式。
将16只挪威棕色大鼠接受单侧巩膜静脉注射高渗盐水以升高眼压。每天用手持眼压计监测眼压，并在手术后8天和5周收集视网膜。使用基因微阵列（大鼠U34A大鼠阵列；Affymetrix，加利福尼亚州圣克拉拉）比较实验视网膜和对侧视网膜之间的mRNA水平。使用半定量RT-PCR来确认阵列分析的选定结果，并与视神经横断后的变化进行比较。
眼压升高5周导致81种mRNA水平出现可重复的变化。其中，74种增加，而只有7种减少。在眼压升高8天后，这些相同信息中的27种的表达水平发生了变化。此外，在较短时间的眼压升高暴露后，另外四个基因也显示出表达改变。表达改变的mRNA中约一半与神经炎症反应或细胞凋亡有关。对于通过阵列分析改变的25条选定的功能相关信息，其改变通过半定量RT-PCR得到证实。在视神经横断后，25条选定信息中的24条的水平也发生了变化。
眼压升高后胶质细胞和补体系统的激活，与几种神经退行性疾病和视神经横断后所描述的情况相似，这表明该大鼠青光眼模型可用于评估针对这些过程的治疗药物的神经保护潜力。
