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Current Hypertension Reports

, Volume 9, Issue 3, pp 222–227 | Cite as

Cardiovascular effects of angiotensin II in the rostral ventrolateral medulla: The push-pull hypothesis

  • R. A. L. DampneyEmail author
  • P. S. P. Tan
  • M. J. Sheriff
  • M. A. P. Fontes
  • J. Horiuchi
Article

Abstract

Neurons within the rostral ventrolateral medulla (RVLM) play a pivotal role in the tonic and phasic control of blood pressure. This region also contains a high density of angiotensin II type 1 (AT1) receptors. There is evidence that tonic activation of AT1 receptors in the RVLM contributes to an increased sympathetic vasomotor activity in some models of hypertension. At the same time, under certain conditions, activation of AT1 receptors in the RVLM can cause sympathoinhibition. In this review we argue that the effect of endogenous angiotensin II in the RVLM on sympathetic vasomotor activity depends upon the balance between tonic excitatory and inhibitory effects on sympathetic premotor neurons mediated by AT1 receptors within this region, and that this balance may be altered in different physiological or pathophysiological conditions.

Keywords

Ventrolateral Medulla Rostral Ventrolateral Medulla AT1a Receptor RVLM Neuron Endogenous Angiotensin 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Current Medicine Group LLC 2007

Authors and Affiliations

  • R. A. L. Dampney
    • 1
    Email author
  • P. S. P. Tan
  • M. J. Sheriff
  • M. A. P. Fontes
  • J. Horiuchi
  1. 1.Department of Physiology, School of Medical Sciences and Bosch InstituteThe University of Sydney F13SydneyAustralia

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