Vinores S A, Van Niel E, Swerdloff J L, Campochiaro P A
Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21287.
Histochem J. 1993 Sep;25(9):648-63. doi: 10.1007/BF00157879.
Light-microscopic immunohistochemical staining for albumin has been used to localize sites of blood-retinal barrier (BRB) breakdown in ocular disorders, but the mechanism for BRB compromise cannot be resolved at this level. Using eyes up to 2 days post-mortem from normal patients or from patients with diabetic retinopathy, or other disorders known to cause BRB failure, electron-microscopic immunocytochemistry reveals focal breakdown of the inner BRB, comprised of the retinal vascular endothelium (RVE), which appears to be mediated by diffuse permeation of the RVE cells and by vesicular transport. Permeation of the retinal pigmented epithelial (RPE) cells that comprise the outer BRB also occurs, but there is no evidence of opening of tight junctions between RVE or RPE in any of the disorders evaluated. Increased aldose reductase (AR) expression in the RVE and RPE cells of diabetics as well as in the perivascular retinal astrocytes, which interact with RVE cells to establish the inner BRB, suggests that AR activity and the subsequent intracellular accumulation of sorbitol in these cell types may impair the function of the BRB in diabetes.
白蛋白的光镜免疫组化染色已被用于定位眼部疾病中血视网膜屏障（BRB）破坏的部位，但在此层面上无法解析BRB受损的机制。使用正常患者或糖尿病视网膜病变患者或其他已知会导致BRB功能障碍的疾病患者死后长达2天的眼睛，电子显微镜免疫细胞化学显示由视网膜血管内皮（RVE）组成的内BRB出现局灶性破坏，这似乎是由RVE细胞的弥漫性渗透和囊泡转运介导的。构成外BRB的视网膜色素上皮（RPE）细胞也会发生渗透，但在所评估的任何疾病中，均未发现RVE或RPE之间紧密连接开放的证据。糖尿病患者的RVE和RPE细胞以及与RVE细胞相互作用以建立内BRB的血管周围视网膜星形胶质细胞中醛糖还原酶（AR）表达增加，这表明AR活性以及这些细胞类型中随后山梨醇的细胞内积累可能会损害糖尿病中BRB的功能。
