Abstract
The goal of this work was to nondestructively measure glomerular (and thereby nephron) number in the whole kidney. Variations in the number and size of glomeruli have been linked to many renal and systemic diseases. Here, we develop a robust magnetic resonance imaging (MRI) technique based on injection of cationic ferritin (CF) to produce an accurate measurement of number and size of individual glomeruli. High-field (19 Tesla) gradient-echo MR images of perfused rat kidneys after in vivo intravenous injection of CF showed specific labeling of individual glomeruli with CF throughout the kidney. We developed a three-dimensional image-processing algorithm to count every labeled glomerulus. MRI-based counts yielded 33,786 ± 3,753 labeled glomeruli (n = 5 kidneys). Acid maceration counting of contralateral kidneys yielded an estimate of 30,585 ± 2,053 glomeruli (n = 6 kidneys). Disector/fractionator stereology counting yielded an estimate of 34,963 glomeruli (n = 2). MRI-based measurement of apparent glomerular volume of labeled glomeruli was 4.89× 10-4 mm3 (n = 5) compared with the average stereological measurement of 4.99× 10-4 mm3 (n = 2). The MRI-based technique also yielded the intrarenal distribution of apparent glomerular volume, a measurement previously unobtainable in histology. This work makes it possible to nondestructively measure whole-kidney glomerular number and apparent glomerular volumes to study susceptibility to renal diseases and opens the door to similar in vivo measurements in animals and humans.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Renal Physiology |
| Volume | 300 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 2011 |
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Keywords
- Glomerulus count
- Magnetic resonance imaging
- Nanoparticles
- Nephron
- Stereology
ASJC Scopus subject areas
- Physiology
- Urology
Cite this
Measuring glomerular number and size in perfused kidneys using MRI. / Beeman, Scott C.; Zhang, Min; Gubhaju, Lina; Wu, Teresa; Bertram, John F.; Frakes, David; Cherry, Brian; Bennett, Kevin M.
In: American Journal of Physiology - Renal Physiology, Vol. 300, No. 6, 06.2011.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Measuring glomerular number and size in perfused kidneys using MRI
AU - Beeman, Scott C.
AU - Zhang, Min
AU - Gubhaju, Lina
AU - Wu, Teresa
AU - Bertram, John F.
AU - Frakes, David
AU - Cherry, Brian
AU - Bennett, Kevin M.
PY - 2011/6
Y1 - 2011/6
N2 - The goal of this work was to nondestructively measure glomerular (and thereby nephron) number in the whole kidney. Variations in the number and size of glomeruli have been linked to many renal and systemic diseases. Here, we develop a robust magnetic resonance imaging (MRI) technique based on injection of cationic ferritin (CF) to produce an accurate measurement of number and size of individual glomeruli. High-field (19 Tesla) gradient-echo MR images of perfused rat kidneys after in vivo intravenous injection of CF showed specific labeling of individual glomeruli with CF throughout the kidney. We developed a three-dimensional image-processing algorithm to count every labeled glomerulus. MRI-based counts yielded 33,786 ± 3,753 labeled glomeruli (n = 5 kidneys). Acid maceration counting of contralateral kidneys yielded an estimate of 30,585 ± 2,053 glomeruli (n = 6 kidneys). Disector/fractionator stereology counting yielded an estimate of 34,963 glomeruli (n = 2). MRI-based measurement of apparent glomerular volume of labeled glomeruli was 4.89× 10-4 mm3 (n = 5) compared with the average stereological measurement of 4.99× 10-4 mm3 (n = 2). The MRI-based technique also yielded the intrarenal distribution of apparent glomerular volume, a measurement previously unobtainable in histology. This work makes it possible to nondestructively measure whole-kidney glomerular number and apparent glomerular volumes to study susceptibility to renal diseases and opens the door to similar in vivo measurements in animals and humans.
AB - The goal of this work was to nondestructively measure glomerular (and thereby nephron) number in the whole kidney. Variations in the number and size of glomeruli have been linked to many renal and systemic diseases. Here, we develop a robust magnetic resonance imaging (MRI) technique based on injection of cationic ferritin (CF) to produce an accurate measurement of number and size of individual glomeruli. High-field (19 Tesla) gradient-echo MR images of perfused rat kidneys after in vivo intravenous injection of CF showed specific labeling of individual glomeruli with CF throughout the kidney. We developed a three-dimensional image-processing algorithm to count every labeled glomerulus. MRI-based counts yielded 33,786 ± 3,753 labeled glomeruli (n = 5 kidneys). Acid maceration counting of contralateral kidneys yielded an estimate of 30,585 ± 2,053 glomeruli (n = 6 kidneys). Disector/fractionator stereology counting yielded an estimate of 34,963 glomeruli (n = 2). MRI-based measurement of apparent glomerular volume of labeled glomeruli was 4.89× 10-4 mm3 (n = 5) compared with the average stereological measurement of 4.99× 10-4 mm3 (n = 2). The MRI-based technique also yielded the intrarenal distribution of apparent glomerular volume, a measurement previously unobtainable in histology. This work makes it possible to nondestructively measure whole-kidney glomerular number and apparent glomerular volumes to study susceptibility to renal diseases and opens the door to similar in vivo measurements in animals and humans.
KW - Glomerulus count
KW - Magnetic resonance imaging
KW - Nanoparticles
KW - Nephron
KW - Stereology
UR - http://www.scopus.com/inward/record.url?scp=79958088469&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79958088469&partnerID=8YFLogxK
U2 - 10.1152/ajprenal.00044.2011
DO - 10.1152/ajprenal.00044.2011
M3 - Article
C2 - 21411479
AN - SCOPUS:79958088469
VL - 300
JO - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
JF - American Journal of Physiology - Renal Fluid and Electrolyte Physiology
SN - 0363-6127
IS - 6
ER -