Russo Leileata M, Bakris George L, Comper Wayne D
Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia.
Am J Kidney Dis. 2002 May;39(5):899-919. doi: 10.1053/ajkd.2002.32764.
Biochemical and physiological processes that underlie the mechanism of albuminuria are completely reassessed in this article in view of recent discoveries that filtered proteins undergo rapid degradation during renal passage and the resulting excreted peptide fragments are not detected by conventional urine protein assays. This means that filtered protein and/or albumin levels in urine have been seriously underestimated. The concept that albuminuria is a result of changes in glomerular permeability is questioned in light of these findings and also in terms of a critical examination of charge selectivity, shunts, or large-pore formation and hemodynamic effects. The glomerulus appears to function merely in terms of size selectivity alone, and for albumin, this does not change significantly in disease states. Intensive albumin processing by a living kidney occurs through cellular processes distal to the glomerular basement membrane. Failure of this cellular processing primarily leads to albuminuria. This review brings together recent data about urinary albumin clearance and current knowledge of receptors known to process albumin in both health and disease states. We conclude with a discussion of topical and controversial issues associated with the proposed new understanding of renal handling of albumin.
鉴于最近的发现，即滤过的蛋白质在肾脏通过过程中会迅速降解，而传统的尿蛋白检测方法无法检测到由此产生的排泄肽片段，本文对蛋白尿机制背后的生化和生理过程进行了全面重新评估。这意味着尿液中滤过的蛋白质和/或白蛋白水平被严重低估。鉴于这些发现，以及对电荷选择性、分流、大孔形成和血流动力学效应的批判性审视，蛋白尿是肾小球通透性改变结果的概念受到质疑。肾小球似乎仅在大小选择性方面起作用，对于白蛋白而言，在疾病状态下这一选择性并无显著变化。活肾对白蛋白的大量处理是通过肾小球基底膜远端的细胞过程进行的。这种细胞处理功能的失败主要导致蛋白尿。本综述汇集了有关尿白蛋白清除率的最新数据以及在健康和疾病状态下已知处理白蛋白的受体的当前知识。我们最后讨论了与提议的对肾脏处理白蛋白的新理解相关的热门和有争议的问题。
