Anderson H R, Stitt A W, Gardiner T A, Archer D B
Department of Ophthalmology, Queen's University of Belfast.
Br J Ophthalmol. 1995 Dec;79(12):1120-3. doi: 10.1136/bjo.79.12.1120.
To assess quantitatively variations in the extent of capillary basement membrane (BM) thickening between different retinal layers and within arterial and venous environments during diabetes.
One year after induction of experimental (streptozotocin) diabetes in rats, six diabetic animals together with six age-matched control animals were sacrificed and the retinas fixed for transmission electron microscopy (TEM). Blocks of retina straddling the major arteries and veins in the central retinal were dissected out, embedded in resin, and sectioned. Capillaries in close proximity to arteries or veins were designated as residing in either an arterial (AE) or a venous (VE) environment respectively, and the retinal layer in which each capillary was located was also noted. The thickness of the BM was then measured on an image analyser based two dimensional morphometric analysis system.
In both diabetics and controls the AE capillaries had consistently thicker BMs than the VE capillaries. The BMs of both AE and VE capillaries from diabetics were thicker than those of capillaries in the corresponding retinal layer from the normal rats (p < or = 0.005). Also, in normal AE and VE capillaries and diabetic AE capillaries the BM in the nerve fibre layer (NFL) was thicker than that in either the inner (IPL) or outer (OPL) plexiform layers (p < or = 0.001). However, in diabetic VE capillaries the BMs of capillaries in the NFL were thicker than those of capillaries in the IPL (p < or = 0.05) which, in turn, had thicker BMs than capillaries in the OPL (p < or = 0.005).
The variation in the extent of capillary BM thickening between different retinal layers within AE and VE environments may be related to differences in levels of oxygen tension and oxidative stress in the retina around arteries compared with that around veins.
定量评估糖尿病期间不同视网膜层之间以及动脉和静脉环境中毛细血管基底膜（BM）增厚程度的变化。
在大鼠实验性（链脲佐菌素）糖尿病诱导一年后，处死6只糖尿病动物和6只年龄匹配的对照动物，将视网膜固定用于透射电子显微镜（TEM）检查。切下横跨视网膜中央主要动脉和静脉的视网膜块，包埋在树脂中并切片。紧邻动脉或静脉的毛细血管分别被指定为处于动脉（AE）或静脉（VE）环境中，同时记录每个毛细血管所在的视网膜层。然后在基于图像分析仪的二维形态计量分析系统上测量BM的厚度。
在糖尿病动物和对照动物中，AE毛细血管的BM始终比VE毛细血管厚。糖尿病动物的AE和VE毛细血管的BM均比正常大鼠相应视网膜层中的毛细血管厚（p≤0.005）。此外，在正常AE和VE毛细血管以及糖尿病AE毛细血管中，神经纤维层（NFL）的BM比内（IPL）或外（OPL）丛状层中的BM厚（p≤0.001）。然而，在糖尿病VE毛细血管中，NFL中毛细血管的BM比IPL中毛细血管的BM厚（p≤0.05），而IPL中毛细血管的BM又比OPL中毛细血管的BM厚（p≤0.005）。
AE和VE环境中不同视网膜层之间毛细血管BM增厚程度的变化可能与动脉周围视网膜与静脉周围视网膜的氧张力水平和氧化应激差异有关。
