Carlson E C, Bjork N J
Department of Anatomy and Cell Biology, School of Medicine, University of North Dakota, Grand Forks 58202.
Anat Rec. 1990 Mar;226(3):295-306. doi: 10.1002/ar.1092260305.
Human retinas from persons with diabetic retinopathy and age-matched controls were rendered acellular by sequential detergent treatment. The resulting network of microvascular extracellular matrix (ECM) materials, including basement membranes (BMs), was compared by TEM and, following cryofracture, by SEM. Our study demonstrates that in diabetics, retinal capillary BM complexes are generally thickened and that their ECM subcomponents, including BM leaflets and BM-like pericytic matrix (PCM), are differentially altered. Two diabetic microvessel types were identified. In type A vessels, ECM expansion is manifested by loosely arranged combinations of concentric PCM layers and collagen fibrils with thickened subendothelial (EBM) and pericyte (PBM) BM leaflets. Type B vessels show densely compact central PCM masses and poorly recognizable EBMs and PBMs. In both types, Müller cell BMs (MBMs) are relatively unaffected. High-resolution SEM shows tissue-specific features in normal EBM and MBM surfaces, but disease-related topographic changes are not evident. It is possible that the ECM arrangements identified in our study relate to different microvessel domains and that their specific morphological features may play important roles in the pathogenesis of diabetic retinopathy including capillary closure and neovascularization.
通过连续的去污剂处理，使患有糖尿病视网膜病变的人和年龄匹配的对照者的人视网膜脱细胞。通过透射电子显微镜（TEM）以及在冷冻断裂后通过扫描电子显微镜（SEM），对由此产生的包括基底膜（BMs）在内的微血管细胞外基质（ECM）材料网络进行了比较。我们的研究表明，在糖尿病患者中，视网膜毛细血管BM复合物通常会增厚，并且其ECM亚成分，包括BM小叶和BM样周细胞基质（PCM），会发生不同程度的改变。识别出两种糖尿病微血管类型。在A型血管中，ECM扩张表现为同心PCM层和胶原纤维的松散排列组合，伴有增厚的内皮下（EBM）和周细胞（PBM）BM小叶。B型血管显示致密紧凑的中央PCM团块以及难以辨认的EBM和PBM。在这两种类型中，Müller细胞BM（MBM）相对未受影响。高分辨率SEM显示正常EBM和MBM表面具有组织特异性特征，但与疾病相关的地形变化并不明显。我们研究中确定的ECM排列可能与不同的微血管区域有关，并且它们的特定形态特征可能在糖尿病视网膜病变的发病机制中起重要作用，包括毛细血管闭塞和新生血管形成。
