A model of oxygen transport in the rat renal medulla

Chang Joon Lee, Bruce S. Gardiner, Roger G. Evans, David W. Smith

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The renal medulla is prone to hypoxia. Medullary hypoxia is postulated to be a leading cause of acute kidney injury, so there is considerable interest in predicting the oxygen tension in the medulla. Therefore we have developed a computational model for blood and oxygen transport within a physiologically normal rat renal medulla, using a multilevel modeling approach. For the top-level model we use the theory of porous media and advection-dispersion transport through a realistic three-dimensional representation of the medulla's gross anatomy to describe blood flow and oxygen transport throughout the renal medulla. For the lower-level models, we employ two-dimensional reaction-diffusion models describing the distribution of oxygen through tissue surrounding the vasculature. Steady-state model predictions at the two levels are satisfied simultaneously, through iteration between the levels. The computational model was validated by simulating eight sets of experimental data regarding renal oxygenation in rats (using 4 sets of control groups and 4 sets of treatment groups, described in 4 independent publications). Predicted medullary tissue oxygen tension or microvascular oxygen tension for control groups and for treatment groups that underwent moderate perturbation in hemodynamic and renal functions is within ±2 SE values observed experimentally. Diffusive shunting between descending and ascending vasa recta is predicted to be only 3% of the oxygen delivered. The validation tests confirm that the computational model is robust and capable of capturing the behavior of renal medullary oxygenation in both normal and early-stage pathological states in the rat.

Original languageEnglish
Pages (from-to)F1787-F1811
JournalAmerican journal of physiology. Renal physiology
Volume315
Issue number6
DOIs
Publication statusPublished - 1 Dec 2018

Fingerprint

Oxygen
Kidney
Control Groups
Acute Kidney Injury
Rectum
Publications
Anatomy
Hemodynamics
Hypoxia

Cite this

@article{c1ba0dfb7aae448b8c1915aaf2d97067,
title = "A model of oxygen transport in the rat renal medulla",
abstract = "The renal medulla is prone to hypoxia. Medullary hypoxia is postulated to be a leading cause of acute kidney injury, so there is considerable interest in predicting the oxygen tension in the medulla. Therefore we have developed a computational model for blood and oxygen transport within a physiologically normal rat renal medulla, using a multilevel modeling approach. For the top-level model we use the theory of porous media and advection-dispersion transport through a realistic three-dimensional representation of the medulla's gross anatomy to describe blood flow and oxygen transport throughout the renal medulla. For the lower-level models, we employ two-dimensional reaction-diffusion models describing the distribution of oxygen through tissue surrounding the vasculature. Steady-state model predictions at the two levels are satisfied simultaneously, through iteration between the levels. The computational model was validated by simulating eight sets of experimental data regarding renal oxygenation in rats (using 4 sets of control groups and 4 sets of treatment groups, described in 4 independent publications). Predicted medullary tissue oxygen tension or microvascular oxygen tension for control groups and for treatment groups that underwent moderate perturbation in hemodynamic and renal functions is within ±2 SE values observed experimentally. Diffusive shunting between descending and ascending vasa recta is predicted to be only 3{\%} of the oxygen delivered. The validation tests confirm that the computational model is robust and capable of capturing the behavior of renal medullary oxygenation in both normal and early-stage pathological states in the rat.",
keywords = "acute kidney injury, computational model, hypoxia, oxygen tension, renal oxygenation",
author = "Lee, {Chang Joon} and Gardiner, {Bruce S.} and Evans, {Roger G.} and Smith, {David W.}",
year = "2018",
month = "12",
day = "1",
doi = "10.1152/ajprenal.00363.2018",
language = "English",
volume = "315",
pages = "F1787--F1811",
journal = "American journal of physiology : renal physiology",
issn = "1522-1466",
publisher = "American Physiological Society",
number = "6",

}

A model of oxygen transport in the rat renal medulla. / Lee, Chang Joon; Gardiner, Bruce S.; Evans, Roger G.; Smith, David W.

In: American journal of physiology. Renal physiology, Vol. 315, No. 6, 01.12.2018, p. F1787-F1811.

Research output: Contribution to journalArticle

TY - JOUR

T1 - A model of oxygen transport in the rat renal medulla

AU - Lee, Chang Joon

AU - Gardiner, Bruce S.

AU - Evans, Roger G.

AU - Smith, David W.

PY - 2018/12/1

Y1 - 2018/12/1

N2 - The renal medulla is prone to hypoxia. Medullary hypoxia is postulated to be a leading cause of acute kidney injury, so there is considerable interest in predicting the oxygen tension in the medulla. Therefore we have developed a computational model for blood and oxygen transport within a physiologically normal rat renal medulla, using a multilevel modeling approach. For the top-level model we use the theory of porous media and advection-dispersion transport through a realistic three-dimensional representation of the medulla's gross anatomy to describe blood flow and oxygen transport throughout the renal medulla. For the lower-level models, we employ two-dimensional reaction-diffusion models describing the distribution of oxygen through tissue surrounding the vasculature. Steady-state model predictions at the two levels are satisfied simultaneously, through iteration between the levels. The computational model was validated by simulating eight sets of experimental data regarding renal oxygenation in rats (using 4 sets of control groups and 4 sets of treatment groups, described in 4 independent publications). Predicted medullary tissue oxygen tension or microvascular oxygen tension for control groups and for treatment groups that underwent moderate perturbation in hemodynamic and renal functions is within ±2 SE values observed experimentally. Diffusive shunting between descending and ascending vasa recta is predicted to be only 3% of the oxygen delivered. The validation tests confirm that the computational model is robust and capable of capturing the behavior of renal medullary oxygenation in both normal and early-stage pathological states in the rat.

AB - The renal medulla is prone to hypoxia. Medullary hypoxia is postulated to be a leading cause of acute kidney injury, so there is considerable interest in predicting the oxygen tension in the medulla. Therefore we have developed a computational model for blood and oxygen transport within a physiologically normal rat renal medulla, using a multilevel modeling approach. For the top-level model we use the theory of porous media and advection-dispersion transport through a realistic three-dimensional representation of the medulla's gross anatomy to describe blood flow and oxygen transport throughout the renal medulla. For the lower-level models, we employ two-dimensional reaction-diffusion models describing the distribution of oxygen through tissue surrounding the vasculature. Steady-state model predictions at the two levels are satisfied simultaneously, through iteration between the levels. The computational model was validated by simulating eight sets of experimental data regarding renal oxygenation in rats (using 4 sets of control groups and 4 sets of treatment groups, described in 4 independent publications). Predicted medullary tissue oxygen tension or microvascular oxygen tension for control groups and for treatment groups that underwent moderate perturbation in hemodynamic and renal functions is within ±2 SE values observed experimentally. Diffusive shunting between descending and ascending vasa recta is predicted to be only 3% of the oxygen delivered. The validation tests confirm that the computational model is robust and capable of capturing the behavior of renal medullary oxygenation in both normal and early-stage pathological states in the rat.

KW - acute kidney injury

KW - computational model

KW - hypoxia

KW - oxygen tension

KW - renal oxygenation

UR - http://www.scopus.com/inward/record.url?scp=85060201767&partnerID=8YFLogxK

U2 - 10.1152/ajprenal.00363.2018

DO - 10.1152/ajprenal.00363.2018

M3 - Article

VL - 315

SP - F1787-F1811

JO - American journal of physiology : renal physiology

JF - American journal of physiology : renal physiology

SN - 1522-1466

IS - 6

ER -