Morano S, D'Erme M, Sensi M, De Rossi M G, Medici F, Galliccia F, Andreani D, Di Mario U
Department of Endocrinology, University of La Sapienza, Roma, Italy.
Biochem Med Metab Biol. 1994 Dec;53(2):92-7. doi: 10.1006/bmmb.1994.1063.
An impairment of protein charge selectivity has been invoked to explain the initial anionic proteinuria in diabetic nephropathy. The aims of this work were to investigate charge and size protein perm-selectivity abnormalities in experimental diabetes and to monitor these changes over time after diabetes induction. Diabetes was induced in 56 Sprague-Dawley male rats by streptozotocin; the control group was represented by 38 normal rats. Blood glucose, body weight, urine volumes, and proteinuria in 24-h urine collections were evaluated at 3, 6, 9, and 12 months of diabetes. The Bradford method and mono- and bidimensional gel electrophoresis were used to determine and characterize proteinuria. Body weight increase was lower (P < 0.05, P < 0.0001, P < 0.05 at 3, 6, and 12 months, respectively), urine volumes were greater (P < 0.001, P < 0.005, P < 0.05 at 6, 9, and 12 months, respectively) and the proteinuria was significantly increased (P < 0.05 at 3 months, P < 0.001 at 6 months, P < 0.01 at 9 months, and P < 0.05 at 12 months) in diabetic rats compared with the control group. When the charge and the size of urine proteins were considered, small (30 kDa) and anionic proteins were found to be mainly excreted in diabetic rats, at 3 months of the disease; at 6 months, higher amounts of albumin and cationic proteins with higher molecular weight (50 kDa) were also found in the urine; at 9 and 12 months the changes previously described were associated with an excretion of proteins weighing about 75 kDa.(ABSTRACT TRUNCATED AT 250 WORDS)
蛋白质电荷选择性受损被认为是糖尿病肾病初期阴离子蛋白尿的原因。本研究旨在调查实验性糖尿病中蛋白质电荷和大小的通透选择性异常，并在糖尿病诱导后的一段时间内监测这些变化。通过链脲佐菌素诱导56只雄性Sprague-Dawley大鼠患糖尿病；38只正常大鼠作为对照组。在糖尿病病程的3、6、9和12个月时，评估血糖、体重、尿量以及24小时尿蛋白量。采用Bradford法和单向及双向凝胶电泳法来测定和表征蛋白尿。糖尿病大鼠体重增加较低（分别在3、6和12个月时P<0.05、P<0.0001、P<0.05），尿量较多（分别在6、9和12个月时P<0.001、P<0.005、P<0.05），蛋白尿显著增加（3个月时P<0.05，6个月时P<0.001，9个月时P<0.01，12个月时P<0.05），与对照组相比有差异。当考虑尿蛋白的电荷和大小时，发现患病3个月的糖尿病大鼠主要排泄小分子（30 kDa）阴离子蛋白；6个月时，尿中还发现了更多的白蛋白和分子量较高（50 kDa）的阳离子蛋白；9个月和12个月时，上述变化伴随着约75 kDa蛋白质的排泄。（摘要截断于250字）
