| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Mathematics, Duke University, Durham, North Carolina 27708-0320; 2 Department of Mathematics, State University of New York, Buffalo, New York 14214-3093; and 3 Department of Physiology and Biophysics, State University of New York, Stony Brook, New York, 11794-8661
A
mathematical model was used to evaluate the potential effects of
limit-cycle oscillations (LCO) on tubuloglomerular feedback (TGF)
regulation of fluid and sodium delivery to the distal tubule. In
accordance with linear systems theory, simulations of steady-state responses to infinitesimal perturbations in single-nephron glomerular filtration rate (SNGFR) show that TGF regulatory ability (assessed as
TGF compensation) increases with TGF gain magnitude 
when is
less than the critical value c, the value at which LCO
emerge in tubular fluid flow and NaCl concentration at the macula
densa. When > c and LCO are present, TGF
compensation is reduced for both infinitesimal and finite perturbations
in SNGFR, relative to the compensation that could be achieved in the
absence of LCO. Maximal TGF compensation occurs when 
c. Even in the absence of perturbations, LCO increase
time-averaged sodium delivery to the distal tubule, while fluid
delivery is little changed. These effects of LCO are consequences of
nonlinear elements in the TGF system. Because increased distal sodium
delivery may increase the rate of sodium excretion, these simulations
suggest that LCO enhance sodium excretion.
kidney, renal hemodynamics, mathematical model, nonlinear dynamics
This article has been cited by other articles:
|
|
 |
|
  O. V. Sosnovtseva, A. N. Pavlov, E. Mosekilde, K.-P. Yip, N.-H. Holstein-Rathlou, and D. J. Marsh Synchronization among mechanisms of renal autoregulation is reduced in hypertensive rats Am J Physiol Renal Physiol, November 1, 2007; 293(5): F1545 - F1555. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. A. Cupples and B. Braam Assessment of renal autoregulation Am J Physiol Renal Physiol, April 1, 2007; 292(4): F1105 - F1123. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Vallon, B. Muhlbauer, and H. Osswald Adenosine and kidney function. Physiol Rev, July 1, 2006; 86(3): 901 - 940. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. T. Layton, L. C. Moore, and H. E. Layton Multistability in tubuloglomerular feedback and spectral complexity in spontaneously hypertensive rats Am J Physiol Renal Physiol, July 1, 2006; 291(1): F79 - F97. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. T. Layton and H. E. Layton A region-based mathematical model of the urine concentrating mechanism in the rat outer medulla. I. Formulation and base-case results Am J Physiol Renal Physiol, December 1, 2005; 289(6): F1346 - F1366. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Walstead and K.-P. Yip Acute arterial hypertension inhibits proximal tubular fluid reabsorption in normotensive rat but not in SHR Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2004; 286(4): R726 - R733. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. R. Oldson, L. C. Moore, and H. E. Layton Effect of sustained flow perturbations on stability and compensation of tubuloglomerular feedback Am J Physiol Renal Physiol, November 1, 2003; 285(5): F972 - F989. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
