Kondo Mineo, Sakai Takao, Komeima Keiichi, Kurimoto Yukihide, Ueno Shinji, Nishizawa Yuji, Usukura Jiro, Fujikado Takashi, Tano Yasuo, Terasaki Hiroko
Department of Ophthalmology, Graduate School of Medicine, Nagoya University, Nagoya, Japan.
Invest Ophthalmol Vis Sci. 2009 Mar;50(3):1371-7. doi: 10.1167/iovs.08-2863. Epub 2008 Dec 13.
To generate a transgenic (Tg) rabbit model of retinal degeneration and to characterize the pattern of degeneration by using histology and electrophysiology.
Rhodopsin Pro347Leu Tg rabbits were generated by BAC transgenesis. Tg rabbits were identified by Southern blot analysis, and the expression levels were measured by quantitative RT-PCR. Retinal histology was examined by light and electron microscopy and immunohistochemistry. Retinal function was assessed by full-field electroretinograms (ERGs).
Six lines of Tg rabbits were generated, and two lines with higher levels of expression showed rod-dominant progressive retinal degeneration. Retinal histology indicated a marked regional variation in the loss of photoreceptors with the central retina more severely affected than the peripheral retina. The characteristics of the ERGs of transgenic rabbits indicated that the rod components of the ERGs were reduced to only 5% by 48 weeks, whereas the cone components remained at 35% in the wild-type at the same time point. The retinal ultrastructure of Tg rabbits showed a large number of small vesicles that accumulated in the extracellular space of the photoreceptors.
To the best of the authors' knowledge, this is the first rabbit model of progressive retinal degeneration. Because rabbits have large eyes and are easy to handle and breed, they will provide a useful animal model for the study of the pathophysiology of and new treatments for retinal degeneration.
构建视网膜变性的转基因（Tg）兔模型，并通过组织学和电生理学方法对变性模式进行特征描述。
通过BAC转基因技术构建视紫红质Pro347Leu Tg兔。通过Southern印迹分析鉴定Tg兔，并通过定量RT-PCR测量表达水平。通过光镜、电镜和免疫组织化学检查视网膜组织学。通过全视野视网膜电图（ERG）评估视网膜功能。
构建了6个Tg兔品系，其中两个高表达品系表现出以视杆细胞为主的进行性视网膜变性。视网膜组织学显示，光感受器丧失存在明显的区域差异，中央视网膜比周边视网膜受影响更严重。转基因兔的ERG特征表明，到48周时，ERG的视杆细胞成分仅降至5%，而在同一时间点，野生型的视锥细胞成分仍为35%。Tg兔的视网膜超微结构显示，大量小泡积聚在光感受器的细胞外空间。
据作者所知，这是首个进行性视网膜变性的兔模型。由于兔眼睛大，易于操作和繁殖，它们将为视网膜变性的病理生理学研究和新治疗方法提供有用的动物模型。
