Haga H J, Andersen K J, Iversen B M, Ofstad J, Dobrota M, Matre R
Medical Department A, University of Bergen, Haukeland Sykehus, Norway.
Kidney Int. 1988 Dec;34(6):766-73. doi: 10.1038/ki.1988.247.
The effect of food restriction (FR) on the kidney cortex lysosomes prepared by rate and isopycnic zonal centrifugation was studied in rats with passive Heymann glomerulonephritis (PHN). FR reduced the renal mass by 41%, but the capacity for handling of labelled endocytosed proteins by the lysosomes was not different from fed PHN rats. While PHN with heavy proteinuria increased the recovery of lysosomal enzymes in the large lysosomes located in the proximal tubule, no changes were observed in FR-PHN rats in spite of significant proteinuria. The density of the small lysosomes was significantly shifted/reduced (from 1,200 and 1,235 g/ml to 1,185 and 1,225 g/ml, respectively) in both fed and FR-PHN rats, suggesting that the handling of extra loads of protein may enhance the absorptive function of small lysosomes found in the lower part of the nephron. FR reduced the mechanical fragility of lysosomes in the kidney cortex of PHN-rats. The highly increased urinary excretion of lysosomal enzymes in fed PHN rats was not observed in FR-PHN rats. As a conclusion, FR reduces both the fragility of lysosomes and the proportion of digestive enzymes in fragile lysosomes. These lysosomal enzymes may be of pathogenic importance in PHN causing cell damage when liberated from disrupted lysosomes.
在被动型海曼肾小球肾炎（PHN）大鼠中，研究了食物限制（FR）对通过速率和等密度区带离心制备的肾皮质溶酶体的影响。FR使肾脏重量减少了41%，但溶酶体处理标记内吞蛋白的能力与喂食的PHN大鼠没有差异。虽然伴有大量蛋白尿的PHN增加了近端小管中大型溶酶体中溶酶体酶的回收率，但尽管有明显蛋白尿，FR-PHN大鼠中未观察到变化。在喂食的和FR-PHN大鼠中，小型溶酶体的密度均显著改变/降低（分别从1200和1235克/毫升降至1185和1225克/毫升），这表明处理额外的蛋白质负荷可能会增强在肾单位下部发现的小型溶酶体的吸收功能。FR降低了PHN大鼠肾皮质中溶酶体的机械脆性。在FR-PHN大鼠中未观察到喂食的PHN大鼠中溶酶体酶尿排泄量的大幅增加。总之，FR降低了溶酶体的脆性以及易碎溶酶体中消化酶的比例。当这些溶酶体酶从破裂的溶酶体中释放出来时，可能在导致细胞损伤的PHN中具有致病重要性。
