Bulletin of Mathematical Biology

, Volume 56, Issue 3, pp 515–546 | Cite as

The effect of solution non-ideality on membrane transport in three-dimensional models of the renal concentrating mechanism

  • Xianqun Wang
  • Anthony S. Wexler
  • Donald J. Marsh


Previous models of the renal concentrating mechanism employ ideal approximations of solution thermodynamics for membrane transport calculation. In three-dimensional models of the renal medulla, predicted urine concentrations reach levels where there idealized approximations begin to break down. In this paper we derive equations that govern membrane transport for non-dilute solutions and use these equations in a three-dimensional model of the concentrating mechanism. New numerical methods were employed that are more stable than those employed previously. Compared to ideal solution models, the urea non-ideality tends to increase predicted osmolarities, whereas NaCl non-ideality decreases predictions.


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Copyright information

© Elsevier Science Ltd 1994

Authors and Affiliations

  • Xianqun Wang
    • 1
  • Anthony S. Wexler
    • 1
  • Donald J. Marsh
    • 2
  1. 1.Department of Mechanical EngineeringUniversity of DelawareNewarkU.S.A.
  2. 2.Department of Medicine and Biological SciencesBrown UniversityProvidenceU.S.A.

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