Dosso A A, Leuenberger P M, Rungger-Brändle E
Laboratory of Cell Biology, University Eye Clinic, Geneva, Switzerland.
Invest Ophthalmol Vis Sci. 1999 Sep;40(10):2405-10.
To document the effect of sustained systemic hypertension on the integrity and ultrastructural morphology of retinal capillaries in diabetic and nondiabetic rats.
Normotensive (strain Wistar-Kyoto; WKY) and genetically hypertensive (spontaneously hypertensive; SHR) rats were rendered diabetic by intravenous streptozotocin injection. At 20 weeks of diabetes, endothelial cells, pericytes, and extracellular matrix were evaluated by ultrastructural morphometry. Serum albumin was localized by immunofluorescence microscopy.
The endothelial cell layer was markedly thinner in the diabetic normotensive animals. The number of intercellular junctions was reduced in both the nondiabetic and diabetic hypertensive group but less so in the diabetic normotensive group. No significant endothelial cell loss was noted in either of the experimental groups, whereas the number of pericytes and the number of their cytoplasmic processes were reduced in diabetic and hypertensive animals. Significant thickening of the basement membrane and increased permeability to serum albumin were observed in diabetic and hypertensive rats and were strongly enhanced in the combined diseases.
Endothelial thinning and shape changes from an elaborate to a simpler form as well as rounding up of the pericytes and loosening of their vascular sheaths indicate remodeling of the vascular wall during chronic diabetes and sustained hypertension, before a characteristic vasculopathy becomes manifest. The combination of diabetes and hypertension enhances these features, as well as basement membrane thickening and breakdown of the blood-retinal barrier.
记录持续性系统性高血压对糖尿病和非糖尿病大鼠视网膜毛细血管完整性及超微结构形态的影响。
通过静脉注射链脲佐菌素使血压正常的大鼠（Wistar-Kyoto品系；WKY）和遗传性高血压大鼠（自发性高血压大鼠；SHR）患糖尿病。糖尿病20周时，通过超微结构形态计量学评估内皮细胞、周细胞和细胞外基质。通过免疫荧光显微镜对血清白蛋白进行定位。
糖尿病血压正常的动物中内皮细胞层明显变薄。非糖尿病和糖尿病高血压组的细胞间连接数量均减少，但糖尿病血压正常组减少程度较轻。两个实验组均未观察到明显的内皮细胞丢失，而糖尿病和高血压动物中的周细胞数量及其细胞质突起数量减少。糖尿病和高血压大鼠的基底膜明显增厚，对血清白蛋白的通透性增加，在两种疾病并存时这种情况更为明显。
内皮细胞变薄以及形态从复杂变为简单，同时周细胞变圆且其血管鞘松弛，表明在特征性血管病变出现之前，慢性糖尿病和持续性高血压期间血管壁发生了重塑。糖尿病和高血压并存会增强这些特征，以及基底膜增厚和血视网膜屏障破坏。
