Mieziewska K, van Veen T, Aguirre G D
Section of Medical Genetics, School of Veterinary Medicine, University of Pennsylvania, Philadelphia.
Invest Ophthalmol Vis Sci. 1993 Oct;34(11):3056-67.
In the retinal disorder progressive rod-cone degeneration (prcd) in miniature poodle dogs, the photoreceptor layer degenerates slowly in the course of 5 to 7 years. Components of the interphotoreceptor matrix form a continuous extracellular lattice around photoreceptors. The purpose was to study the photoreceptor cell-matrix interactions during the disease and degeneration phases. Because degeneration rate was slower in cones, the authors also wanted to investigate whether there was a link between the degeneration and the photoreceptor-specific interphotoreceptor matrix domains.
Rod- and cone-specific interphotoreceptor matrix domains were examined during two periods: before morphological signs of disease had appeared and during the degenerative stages. Two lectin probes were used; wheat germ agglutinin and peanut agglutinin. By their affinity for terminal carbohydrates, the lectins visually separated the two photoreceptor-specific domains and allowed follow-up of the fate of the rod and cone matrices separately.
Before and during the course of disease, the lectin distribution in rod and cone domains remained normal, however, in the degenerative phase of the disease, there were structural changes in the matrix domains. The matrix connections between the individual domains was disrupted and single domains were formed. Cone domains and, to a lesser degree rod domains, were thickened around the inner and outer segments.
The changes occurring in the photoreceptor-specific domains were indicative of structural adaptation to cell death and to degenerative conditions. There was no evidence of an active involvement of the interphotoreceptor matrix components studied in the disease process.
在迷你贵宾犬的视网膜疾病进行性视杆-视锥细胞变性（prcd）中，光感受器层在5至7年的病程中缓慢退化。光感受器间基质的成分在光感受器周围形成连续的细胞外晶格。目的是研究疾病和退化阶段光感受器细胞与基质之间的相互作用。由于视锥细胞的退化速度较慢，作者还想研究退化与光感受器特异性光感受器间基质结构域之间是否存在联系。
在两个阶段检查视杆和视锥特异性光感受器间基质结构域：疾病形态学迹象出现之前和退化阶段。使用了两种凝集素探针；麦胚凝集素和花生凝集素。通过它们对末端碳水化合物的亲和力，凝集素在视觉上分离了两个光感受器特异性结构域，并允许分别追踪视杆和视锥基质的命运。
在疾病发生之前和过程中，视杆和视锥结构域中的凝集素分布保持正常，然而，在疾病的退化阶段，基质结构域出现了结构变化。各个结构域之间的基质连接被破坏，形成了单个结构域。视锥结构域以及程度较轻的视杆结构域在内段和外段周围增厚。
光感受器特异性结构域中发生的变化表明其对细胞死亡和退化状况的结构适应性。在所研究的疾病过程中，没有证据表明光感受器间基质成分积极参与其中。
