Glomerular filtration rate dependence of sieving of albumin and some neutral proteins in rat kidneys
(2003) In American Journal of Physiology: Renal, Fluid and Electrolyte Physiology 284(6). p.1226-1234- Abstract
- The size and charge-selective properties of the glomerular barrier are partly controversial. Glomerular sieving coefficients (theta) for proteins have rarely been determined noninvasively before in vivo. Therefore, theta was assessed vs. glomerular filtration rate (GFR; Cr-51-EDTA clearance) in intact rats for radiolabeled myoglobin, kappa-dimer, neutral horseradish peroxidase (nHRP), neutral human serum albumin (nHSA), and native albumin (HSA). To obtain theta, glomerular tracer clearance, assessed from the 7- to 8-min kidney uptake of protein, was divided by the GFR. The data were fitted with a two-pore model of glomerular permeability, where the small-pore radius was 37.35 +/- 1.11(SE) Angstrom, and the "unrestricted pore area over... (More)
- The size and charge-selective properties of the glomerular barrier are partly controversial. Glomerular sieving coefficients (theta) for proteins have rarely been determined noninvasively before in vivo. Therefore, theta was assessed vs. glomerular filtration rate (GFR; Cr-51-EDTA clearance) in intact rats for radiolabeled myoglobin, kappa-dimer, neutral horseradish peroxidase (nHRP), neutral human serum albumin (nHSA), and native albumin (HSA). To obtain theta, glomerular tracer clearance, assessed from the 7- to 8-min kidney uptake of protein, was divided by the GFR. The data were fitted with a two-pore model of glomerular permeability, where the small-pore radius was 37.35 +/- 1.11(SE) Angstrom, and the "unrestricted pore area over diffusion path length" (A(0)/DeltaX) 1.84 +/- 0.43 . 10(6) cm. Although seemingly horizontal for nHRP and nHSA, the log theta vs. GFR curves showed slightly negative slopes for the proteins investigated in the GFR interval of 2-4.5 ml/min. Strong negative ( linear) correlations between ( log) theta and GFR were obtained for myoglobin (P = 0.002) and HSA (P = 0.006), whereas they were relatively weak for nHRP and nHSA and nonsignificant for kappa-dimer. theta for nHSA was markedly higher than that for HSA. In conclusion, there were no indications of increases in theta vs. GFR, as indicative of concentration polarization, for the proteins investigated at high GFRs. Furthermore, the glomerular small-pore radius assessed from endogenous (neutral) protein sieving data was found to be smaller than previously determined using dextran or Ficoll as test molecules. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/312332
- author
- Lund, Ulla LU ; Rippe, Anna LU ; Venturoli, Daniele LU ; Tenstad, O ; Grubb, Anders LU and Rippe, Bengt LU
- organization
- publishing date
- 2003
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- glomerular permeability, transport, reflection coefficient, macromolecules
- in
- American Journal of Physiology: Renal, Fluid and Electrolyte Physiology
- volume
- 284
- issue
- 6
- pages
- 1226 - 1234
- publisher
- American Physiological Society
- external identifiers
-
- wos:000182700200012
- pmid:12620929
- scopus:0037609543
- ISSN
- 0363-6127
- DOI
- 10.1152/ajprenal.00316.2002
- language
- English
- LU publication?
- yes
- id
- eba789a6-dad5-4823-b8e9-065c92ed8274 (old id 312332)
- date added to LUP
- 2016-04-01 12:17:19
- date last changed
- 2023-03-26 23:53:52
@article{eba789a6-dad5-4823-b8e9-065c92ed8274, abstract = {{The size and charge-selective properties of the glomerular barrier are partly controversial. Glomerular sieving coefficients (theta) for proteins have rarely been determined noninvasively before in vivo. Therefore, theta was assessed vs. glomerular filtration rate (GFR; Cr-51-EDTA clearance) in intact rats for radiolabeled myoglobin, kappa-dimer, neutral horseradish peroxidase (nHRP), neutral human serum albumin (nHSA), and native albumin (HSA). To obtain theta, glomerular tracer clearance, assessed from the 7- to 8-min kidney uptake of protein, was divided by the GFR. The data were fitted with a two-pore model of glomerular permeability, where the small-pore radius was 37.35 +/- 1.11(SE) Angstrom, and the "unrestricted pore area over diffusion path length" (A(0)/DeltaX) 1.84 +/- 0.43 . 10(6) cm. Although seemingly horizontal for nHRP and nHSA, the log theta vs. GFR curves showed slightly negative slopes for the proteins investigated in the GFR interval of 2-4.5 ml/min. Strong negative ( linear) correlations between ( log) theta and GFR were obtained for myoglobin (P = 0.002) and HSA (P = 0.006), whereas they were relatively weak for nHRP and nHSA and nonsignificant for kappa-dimer. theta for nHSA was markedly higher than that for HSA. In conclusion, there were no indications of increases in theta vs. GFR, as indicative of concentration polarization, for the proteins investigated at high GFRs. Furthermore, the glomerular small-pore radius assessed from endogenous (neutral) protein sieving data was found to be smaller than previously determined using dextran or Ficoll as test molecules.}}, author = {{Lund, Ulla and Rippe, Anna and Venturoli, Daniele and Tenstad, O and Grubb, Anders and Rippe, Bengt}}, issn = {{0363-6127}}, keywords = {{glomerular permeability; transport; reflection coefficient; macromolecules}}, language = {{eng}}, number = {{6}}, pages = {{1226--1234}}, publisher = {{American Physiological Society}}, series = {{American Journal of Physiology: Renal, Fluid and Electrolyte Physiology}}, title = {{Glomerular filtration rate dependence of sieving of albumin and some neutral proteins in rat kidneys}}, url = {{http://dx.doi.org/10.1152/ajprenal.00316.2002}}, doi = {{10.1152/ajprenal.00316.2002}}, volume = {{284}}, year = {{2003}}, }