Sauvé Y, Klassen H, Whiteley S J, Lund R D
Department of Pathology, Institute of Ophthalmology, London, EC1V 9EL, United Kingdom.
Exp Neurol. 1998 Aug;152(2):243-50. doi: 10.1006/exnr.1998.6849.
The consequences of progressive retinal degeneration on central visual function were studied by recording single and multiunit receptive fields (RFs) across the surface of the superior colliculus (SC) of pigmented dystrophic RCS rats. Retinal morphology was used to provide a correlation between function and histological appearance. In addition, the potential protective effect of retinal pigment epithelium (RPE) transplantation was studied in a similar manner in dystrophic animals in which RPE cells were injected into the subretinal space, or the vitreous humor, at between 21 and 28 days of age. The visual responsiveness of SC units in dystrophic rats differed markedly from those in nondystrophics. Dystrophic rats developed a relative scotoma beginning in the central visual field by 42-45 days of age and expanding to include 50% of the visual field by 97-107 days. In contrast, following subretinal RPE transplantation, there was photoreceptor rescue correlated with a partial to complete preservation of RF representation when examined at 85 to 108 days of age. The majority of photoreceptor rescue occurred in the region of graft placement with possible low level rescue across the central retina. Dystrophic animals that had received intravitreal RPE transplants showed poor photoreceptor survival as well as minimal functional preservation. Our results indicate that there is a progressive central to peripheral loss of visual responsiveness in the SC of dystrophic RCS rats which can be limited by subretinal injections of healthy RPE cells.
通过记录色素性营养不良RCS大鼠上丘（SC）表面的单单位和多单位感受野（RFs），研究了进行性视网膜变性对中心视觉功能的影响。利用视网膜形态学来提供功能与组织学外观之间的相关性。此外，以类似方式研究了视网膜色素上皮（RPE）移植对营养不良动物的潜在保护作用，这些动物在21至28日龄时将RPE细胞注入视网膜下间隙或玻璃体内。营养不良大鼠的SC单位视觉反应性与非营养不良大鼠明显不同。营养不良大鼠在42 - 45日龄时开始在中心视野出现相对暗点，并在97 - 107日龄时扩展至包括50%的视野。相比之下，视网膜下RPE移植后，在85至108日龄检查时，有光感受器挽救现象，且与RF表征的部分至完全保留相关。大多数光感受器挽救发生在移植部位，中央视网膜可能有低水平的挽救。接受玻璃体内RPE移植的营养不良动物光感受器存活情况较差，功能保留也极少。我们的结果表明，营养不良的RCS大鼠的SC中存在从中心到外周的视觉反应性逐渐丧失的情况，而视网膜下注射健康的RPE细胞可以限制这种丧失。
