Cellular and Molecular Mechanisms of Renal Phosphate Transport
Cellular and Molecular Mechanisms of Renal Phosphate Transport
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DOI：
10.1359/jbmr.1997.12.2.159
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发表时间：
1997-02
影响因子：
6.2
通讯作者：
H. Tenenhouse
中科院分区：
文献类型：
--
作者：
H. Tenenhouse
(Pi) 稳态，因此在骨矿化和生长中起着关键作用。大部分过滤后的 Pi 在近端小管中被重吸收，大约 60% 的过滤负载在近曲小管中回收，15-20% 在近端直管中回收。此外，过滤后的 Pi 的一小部分（10%）在肾单位更远端的部分被重吸收。肾脏重吸收 Pi 的总体能力可以通过测量每单位体积肾小球滤液中 Pi 的最大肾小管容量 (Tm) (TmPi/GFR) 来估计。实际上，这是通过在急性 Pi 输注期间测量 Pi 和肌酐排泄以及血浆浓度来实现的。 (1) 人们投入了大量精力来研究近曲小管中 Pi 的转运，这是其重吸收的主要部位（有关评论，请参见参考文献 2-8）。各种各样的实验系统，从完整的动物到囊泡膜制剂，已被用来表征近端肾小管 Pi 转运系统并阐明其调节机制。在克隆编码肾脏特异性Na 1 -Pi协同转运蛋白的cDNA的最新进展以及应用这些新工具研究Na 1 -Pi协同转运蛋白基因在孟德尔肾Pi重吸收障碍中的作用的背景下，对这些问题进行了简要回顾。 (9-13)
(Pi) homeostasis and, as such, plays a key role in bone mineralization and growth. The bulk of filtered Pi is reabsorbed in the proximal tubule, with approximately 60% of the filtered load reclaimed in the proximal convoluted tubule and 15‐20% in the proximal straight tubule. In addition, a small but variable portion (,10%) of filtered Pi is reabsorbed in more distal segments of the nephron. The overall capacity of the kidney to reabsorb Pi can be estimated by measuring the maximum tubular capacity (Tm) for Pi per unit volume of glomerular filtrate (TmPi/GFR). In practice, this is achieved by measuring Pi and creatinine excretions and plasma concentrations during acute Pi infusions. (1) Considerable effort has been devoted to the study of Pi transport in the proximal tubule, the principal site of its reabsorption (for reviews, see Refs. 2‐8). A wide variety of experimental systems, from the intact animal to vesicular membrane preparations, have been used to characterize proximal tubular Pi transport systems and to elucidate mechanisms involved in their regulation. These issues are briefly reviewed in the context of recent advances in the cloning of cDNAs encoding renal-specific Na 1 -Pi cotransporters and the application of these new tools to study the role of Na 1 -Pi cotransporter genes in Mendelian disorders of renal Pi reabsorption. (9‐13)