HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 292/4/F1105    most recent 00194.2006v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Cupples, W. A. Articles by Braam, B. Search for Related Content PubMed PubMed Citation Articles by Cupples, W. A. Articles by Braam, B.

INVITED REVIEW

Assessment of renal autoregulation

¹Centre for Biomedical Research, Department of Biology, University of Victoria, Victoria, British Columbia; and ²Departments of Medicine and Physiology, University of Alberta, Edmonton, Alberta, Canada

The kidney displays highly efficient autoregulation so that under steady-state conditions renal blood flow (RBF) is independent of blood pressure over a wide range of pressure. Autoregulation occurs in the preglomerular microcirculation and is mediated by two, perhaps three, mechanisms. The faster myogenic mechanism and the slower tubuloglomerular feedback contribute both directly and interactively to autoregulation of RBF and of glomerular capillary pressure. Multiple experiments have been used to study autoregulation and can be considered as variants of two basic designs. The first measures RBF after multiple stepwise changes in renal perfusion pressure to assess how a biological condition or experimental maneuver affects the overall pressure-flow relationship. The second uses time-series analysis to better understand the operation of multiple controllers operating in parallel on the same vascular smooth muscle. There are conceptual and experimental limitations to all current experimental designs so that no one design adequately describes autoregulation. In particular, it is clear that the efficiency of autoregulation varies with time and that most current techniques do not adequately address this issue. Also, the time-varying and nonadditive interaction between the myogenic mechanism and tubuloglomerular feedback underscores the difficulty of dissecting their contributions to autoregulation. We consider the modulation of autoregulation by nitric oxide and use it to illustrate the necessity for multiple experimental designs, often applied iteratively.

renal blood flow; myogenic mechanism; tubuloglomerular feedback; interaction

This article has been cited by other articles:

				N. Kleinstreuer, T. David, M. J. Plank, and Z. Endre Dynamic myogenic autoregulation in the rat kidney: a whole-organ model Am J Physiol Renal Physiol, June 1, 2008; 294(6): F1453 - F1464. [Abstract] [Full Text] [PDF]

				K. A. Griffin, M. Abu-Naser, I. Abu-Amarah, M. Picken, G. A. Williamson, and A. K. Bidani Dynamic blood pressure load and nephropathy in the ZSF1 (fa/facp) model of type 2 diabetes Am J Physiol Renal Physiol, November 1, 2007; 293(5): F1605 - F1613. [Abstract] [Full Text] [PDF]

				F. S. Michel, R. Y. K. Man, and P. M. Vanhoutte Increased spontaneous tone in renal arteries of spontaneously hypertensive rats Am J Physiol Heart Circ Physiol, September 1, 2007; 293(3): H1673 - H1681. [Abstract] [Full Text] [PDF]