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Title: Visualization of Three-Dimensional Nephron Structure With Microcomputed Tomography

Abstract

The three-dimensional architecture of nephrons in situ and their interrelationship with other nephrons are difficult to visualize by microscopic methods. The present study uses microcomputed X-ray tomography (micro-CT) to visualize intact nephrons in situ. Rat kidneys were perfusion-fixed with buffered formalin and their vasculature was subsequently perfused with radiopaque silicone. Cortical tissue was stained en bloc with osmium tetroxide, embedded in plastic, scanned, and reconstructed at voxel resolutions of 6, 2, and 1 {mu}m. At 6 {mu}m resolution, large blood vessels and glomeruli could be visualized but nephrons and their lumens were small and difficult to visualize. Optimal images were obtained using a synchrotron radiation source at 2 {mu}m resolution where nephron components could be identified, correlated with histological sections, and traced. Proximal tubules had large diameters and opaque walls, whereas distal tubules, connecting tubules, and collecting ducts had smaller diameters and less opaque walls. Blood vessels could be distinguished from nephrons by the luminal presence of radiopaque silicone. Proximal tubules were three times longer than distal tubules. Proximal and distal tubules were tightly coiled in the outer cortex but were loosely coiled in the middle and inner cortex. The connecting tubules had the narrowest diameters of the tubules andmore » converged to form arcades that paralleled the radial vessels as they extended to the outer cortex. These results illustrate a potential use of micro-CT to obtain three-dimensional information about nephron architecture and nephron interrelationships, which could be useful in evaluating experimental tubular hypertrophy, atrophy, and necrosis.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930372
Report Number(s):
BNL-81093-2008-JA
Journal ID: ISSN 0003-276X; ANREAK; TRN: US0901374
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Anatomical Record; Journal Volume: 290
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ATROPHY; BLOOD VESSELS; DUCTS; FORMALDEHYDE; GLOMERULI; HYPERTROPHY; KIDNEYS; NECROSIS; OSMIUM; PHENOBARBITAL; RATS; RESOLUTION; SYNCHROTRON RADIATION SOURCES; TOMOGRAPHY; TUBULES; national synchrotron light source

Citation Formats

Bentley,M., Jorgensen, S., Lerman, L., Ritman, E., and Romero, J. Visualization of Three-Dimensional Nephron Structure With Microcomputed Tomography. United States: N. p., 2007. Web. doi:10.1002/ar.20422.
Bentley,M., Jorgensen, S., Lerman, L., Ritman, E., & Romero, J. Visualization of Three-Dimensional Nephron Structure With Microcomputed Tomography. United States. doi:10.1002/ar.20422.
Bentley,M., Jorgensen, S., Lerman, L., Ritman, E., and Romero, J. Mon . "Visualization of Three-Dimensional Nephron Structure With Microcomputed Tomography". United States. doi:10.1002/ar.20422.
@article{osti_930372,
title = {Visualization of Three-Dimensional Nephron Structure With Microcomputed Tomography},
author = {Bentley,M. and Jorgensen, S. and Lerman, L. and Ritman, E. and Romero, J.},
abstractNote = {The three-dimensional architecture of nephrons in situ and their interrelationship with other nephrons are difficult to visualize by microscopic methods. The present study uses microcomputed X-ray tomography (micro-CT) to visualize intact nephrons in situ. Rat kidneys were perfusion-fixed with buffered formalin and their vasculature was subsequently perfused with radiopaque silicone. Cortical tissue was stained en bloc with osmium tetroxide, embedded in plastic, scanned, and reconstructed at voxel resolutions of 6, 2, and 1 {mu}m. At 6 {mu}m resolution, large blood vessels and glomeruli could be visualized but nephrons and their lumens were small and difficult to visualize. Optimal images were obtained using a synchrotron radiation source at 2 {mu}m resolution where nephron components could be identified, correlated with histological sections, and traced. Proximal tubules had large diameters and opaque walls, whereas distal tubules, connecting tubules, and collecting ducts had smaller diameters and less opaque walls. Blood vessels could be distinguished from nephrons by the luminal presence of radiopaque silicone. Proximal tubules were three times longer than distal tubules. Proximal and distal tubules were tightly coiled in the outer cortex but were loosely coiled in the middle and inner cortex. The connecting tubules had the narrowest diameters of the tubules and converged to form arcades that paralleled the radial vessels as they extended to the outer cortex. These results illustrate a potential use of micro-CT to obtain three-dimensional information about nephron architecture and nephron interrelationships, which could be useful in evaluating experimental tubular hypertrophy, atrophy, and necrosis.},
doi = {10.1002/ar.20422},
journal = {Anatomical Record},
number = ,
volume = 290,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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