Han K, Zhou H, Pfeifer U
Department of Pathology, University of Bonn, Germany.
Kidney Blood Press Res. 1997;20(4):258-63. doi: 10.1159/000174155.
Cellular autophagy in the cells of distal tubular segments (DT cells) of the kidney cortex in streptozotocin-diabetic rats was evaluated by quantitative electron microscopy. Five days after streptozotocin administration, volume and numerical densities of autophagic vacuoles (AVs) in DT cells were reduced by 56 and 57%, respectively. The correction of the diabetic state by insulin injection reversed the inhibition of cellular autophagy. Volume and numerical densities of AVs increased by 97 and 53%, respectively. Endogenous insulin replacement by islet transplantation showed the same effect on cellular autophagy. Volume and numerical densities of AVs increased by 82 and 34%, respectively, as compared with sham-operated diabetic animals. The data show that, during diabetic kidney hypertrophy, the cellular autophagy is inhibited in DT cells to the same extent as in proximal tubular cells, suggesting that DT cells contribute in a balanced manner to hypertrophic growth of the kidney cortex. Similarly, DT cells are involved in the catabolic reaction, i.e., stimulation of autophagy, after metabolic correction of the diabetic state by insulin.
通过定量电子显微镜评估链脲佐菌素诱导的糖尿病大鼠肾皮质远端小管段（DT细胞）中的细胞自噬。给予链脲佐菌素五天后，DT细胞中自噬泡（AVs）的体积密度和数量密度分别降低了56%和57%。胰岛素注射纠正糖尿病状态可逆转细胞自噬的抑制。AVs的体积密度和数量密度分别增加了97%和53%。胰岛移植进行内源性胰岛素替代对细胞自噬有相同作用。与假手术糖尿病动物相比，AVs的体积密度和数量密度分别增加了82%和34%。数据表明，在糖尿病性肾肥大期间，DT细胞中的细胞自噬与近端小管细胞受到同等程度的抑制，提示DT细胞以平衡的方式参与肾皮质的肥大生长。同样，在通过胰岛素对糖尿病状态进行代谢纠正后，DT细胞参与分解代谢反应，即自噬的刺激。
