The development a new glaucoma model and the identification of the factors inducing glaucomatous neuropathy

在本研究中，我们首次尝试通过将细胞毒性基因转移到小梁网（房水流出系统的主要结构）来建立一种新的青光眼模型大鼠。我们采用HVJ包膜载体，一种已被报道以有效和安全的方式递送靶基因的杂合载体。我们将含有CMV启动子下亚克隆报告基因的质粒DNA的HVJ包膜载体注射到大鼠前房中。在注射后4周内，与对照眼相比，小梁网中没有显著的报告基因表达。为了寻找一种可靠的青光眼模型，我们制作了几种青光眼模型大鼠，发现巩膜上静脉阻塞术可以在手术损伤小的情况下诱发慢性高眼压。巩膜外静脉阻塞模型显示，治疗后12周视网膜神经节细胞（RGCs）数量减少30%，治疗后30周RGCs丢失和视盘杯状变更明显。在其他视网膜神经元中没有观察到明显的变化，而Muller胶质细胞表达了指示反应性条件的标记物。在IOP升高的早期阶段，视神经内的星形胶质细胞表现出细胞死亡的标志物caspase 3的表达增加，先于星形胶质细胞数量的减少。治疗12周后对视盘的微阵列分析显示，参与细胞粘附、细胞外基质形成、细胞周期调控的一些基因受到影响，并且正在进行深入研究以寻找诱导青光眼性神经病变的因素。

In this study, we first tried to develop a new glaucoma model rat by transferring the cytotoxic gene to the trabecular meshwork, a main structure in the outflow system of aqueous humor. We employed HVJ envelope vector, a hybrid vector which has been reported to deliver the target gene in an efficient and a safe manner. We injected the HVJ envelope vector, containing the plasmid DNA which is subcloned reporter gene under the CMV promoter, into the anterior chamber of rats. During the period of 4 weeks after injection, there was no significant expression of reporter gene in the trabecular meshwork, compared to control eyes. To find a reliable glaucoma model, we made several kinds of glaucoma model rat and found out that the episcleral vein occulusion could induce chronic ocular hypertension with little surgical damage. Episcleral vein occulusion model showed the 30% decrease in number of retinal ganglion cells(RGCs) at 12 weeks after treatment, and the loss of RGCs and the cupping of optic disc were more significant at 30 weeks after treatment. There observed no gross changes in other retinal neurons, while Muller glia expressed the markers that indicate the reactive condition. During the early phase of IOP elevation, astrocytes within the optic nerve showed the increased expression of caspase 3, a marker for cell death, preceding the decrease in number of astrocytes. Microarray analysis for optic disc at 12 weeks after treatment, revealed that some of the genes involved in the cell adhesion, the formation of extracellular matrix, the regulation of cell cycle, were affected and the intensive study to find the factors to induce glaucomatous neuropathy is underway.