Moriya Tatsumi, Ohno Shinichi, Tanaka Keiji, Fujita Yoshikuni
Department of Endocrinology, Diabetes and Metabolism, Kitasato University School of Medicine 1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555, Japan.
J Electron Microsc (Tokyo). 2006 Apr;55(2):69-73. doi: 10.1093/jmicro/dfl010. Epub 2006 Jun 1.
Mesangial expansion and glomerular basement membrane (GBM) thickening were not different between normoalbuminuric (NA) and microalbuminuric (MA) type 2 diabetic patients. The quick-freezing and deep-etching (QF-DE) method allows us to examine three-dimensional ultrastructures of human renal glomeruli in vivo at high resolution. In the present study, the QF-DE method was applied to the renal biopsy from 6 type 2 diabetic patients without definable renal diseases other than diabetic nephropathy. Four patients were NA and the other two were MA. Three control specimens were normal parts in surgically resected kidneys of renal cell carcinoma. Replica membranes were prepared by the QF-DE method as previously described. By the QF-DE method, both GBM middle layer and mesangial matrix (MM) were composed of polygonal meshwork structures. The mesh pores of GBM and MM were more enlarged in size and irregular in shape in NA diabetic patients than those of the controls, and these ultrastructural changes became more obvious in MA patients. The diameters of mesh pores in the diabetic patients were significantly larger than those in the control subjects. In conclusion, the QF-DE method could be applied to needle renal biopsy and the present study has firstly clarified the difference of ultrastructural changes between NA and MA type 2 diabetic patients, which had not been disclosed by the conventional electron microscopy, were revealed by the QF-DE method.
在正常白蛋白尿（NA）和微量白蛋白尿（MA）的2型糖尿病患者中，系膜扩张和肾小球基底膜（GBM）增厚情况并无差异。快速冷冻与深度蚀刻（QF-DE）方法使我们能够在体内以高分辨率检查人类肾小球的三维超微结构。在本研究中，QF-DE方法应用于6例2型糖尿病患者的肾活检，这些患者除糖尿病肾病外无其他明确的肾脏疾病。4例为NA患者，另外2例为MA患者。3个对照标本取自肾细胞癌手术切除肾脏的正常部分。如前所述，通过QF-DE方法制备复膜。通过QF-DE方法观察到，GBM中层和系膜基质（MM）均由多边形网格结构组成。与对照组相比，NA糖尿病患者GBM和MM的网孔尺寸更大且形状不规则，并且这些超微结构变化在MA患者中更为明显。糖尿病患者的网孔直径显著大于对照受试者。总之，QF-DE方法可应用于经皮肾穿刺活检，本研究首次阐明了NA和MA 2型糖尿病患者超微结构变化的差异，而传统电子显微镜未揭示这些差异，QF-DE方法则揭示了这些差异。
