Nephron morphometry in mice and rats using tomographic microscopy
Nephron morphometry in mice and rats using tomographic microscopy
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使用断层扫描显微镜测量小鼠和大鼠的肾单位形态
DOI：
10.1152/ajprenal.00207.2016
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发表时间：
2017-01-01
影响因子：
4.2
通讯作者：
Andreasen, Arne
中科院分区：
文献类型：
--
作者：
Letts, Robyn F. R.;Zhai, Xiao-Yue;Andreasen, Arne
目的是量化小鼠和大鼠肾脏中单个肾单位的肾小球毛细血管表面积、节段性肾小管半径、长度和面积。取3只小鼠和3只大鼠肾脏，取多个2.5微米厚的EPON连续切片，进行肾小管三维重建。对每个肾脏的显微照片进行了比对，追踪了359个肾单位，并对其节段进行了定位。选取30只小鼠和30只大鼠肾单位进行进一步研究。用两种方法确定各节段的管腔半径。根据各节段的半径和长度估算管腔表面积。记录5只大鼠肾小球的高分辨率显微照片，并测定毛细血管表面积。根据肾小球收缩校正毛细血管体积和表面积。肾小球毛细血管面积与近曲小管面积呈正相关。肾单位最厚的部分，即近端小管，紧随其后的是肾单位的最薄的部分，即下降的细肢，所识别的7个肾单位的直径在两种动物中具有相同的排名。小鼠和大鼠肾单位的半径和长度测量结果基本相同；大鼠肾小管半径与小鼠肾小管半径之比接近1.47，大鼠肾小管长度与小鼠肾小管长度之比接近2.29，表明大鼠肾小管相对较长。小鼠和大鼠肾小球毛细血管面积和节段半径、长度和面积值的详细表格可以用来增强对相关生理学的理解，包括现有的尿液浓缩机制的稳态模型。
The aim was to quantify the glomerular capillary surface area, the segmental tubular radius, length, and area of single nephrons in mouse and rat kidneys. Multiple 2.5-mu m-thick serial Epon sections were obtained from three mouse and three rat kidneys for three-dimensional reconstruction of the nephron tubules. Micrographs were aligned for each kidney, and 359 nephrons were traced and their segments localized. Thirty mouse and thirty rat nephrons were selected for further investigation. The luminal radius of each segment was determined by two methods. The luminal surface area was estimated from the radius and length of each segment. High-resolution micrographs were recorded for five rat glomeruli, and the capillary surface area determined. The capillary volume and surface area were corrected for glomerular shrinkage. A positive correlation was found between glomerular capillary area and proximal tubule area. The thickest part of the nephron, i.e., the proximal tubule, was followed by the thinnest part of the nephron, i.e., the descending thin limb, and the diameters of the seven identified nephron segments share the same rank in the two species. The radius and length measurements from mouse and rat nephrons generally share the same pattern; rat tubular radius-to-mouse tubular radius ratio approximate to 1.47, and rat tubular length-to-mouse tubular length ratio approximate to 2.29, suggesting relatively longer tubules in the rat. The detailed tables of mouse and rat glomerular capillary area and segmental radius, length, and area values may be used to enhance understanding of the associated physiology, including existing steady-state models of the urine-concentrating mechanism.