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: 286/5/H1665    most recent 00858.2003v1 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 (15) Citing Articles via Google Scholar Google Scholar Articles by Tan, J. Articles by Leenen, F. H. H. Search for Related Content PubMed PubMed Citation Articles by Tan, J. Articles by Leenen, F. H. H.

Increases in brain and cardiac AT₁ receptor and ACE densities after myocardial infarct in rats

Hypertension Unit, University of Ottawa Heart Institute, Ottawa, Ontario, Canada K1Y 4W7

Submitted 8 September 2003 ; accepted in final form 18 December 2003

In the brain, ouabain-like compounds (OLC) and the reninangiotensin system (RAS) contribute to sympathetic hyperactivity in rats after myocardial infarction (MI). This study aimed to evaluate changes in components of the central vs. the peripheral RAS. Angiotensin-converting enzyme (ACE) and angiotensin type 1 (AT₁) receptor binding densities were determined by measuring ¹²⁵I-labeled 351A and ¹²⁵I-labeled ANG II binding 4 and 8 wk after MI. In the brain, ACE and AT₁ receptor binding increased 8–15% in the subfornical organ, 14–22% in the organum vasculosum laminae terminalis, 20–34% in the paraventricular nucleus, and 13–15% in the median preoptic nucleus. In the heart, the greatest increase in ACE and AT₁ receptor binding occurred at the infarct scar (10-fold) and the least in the right ventricle (2-fold). In kidneys, ACE and AT₁ receptor binding decreased 10–15%. After intracerebroventricular infusion of Fab fragments to block brain OLC from 0.5 to 4 wk after MI, increases in ACE and AT₁ receptors in the subfornical organ, organum vasculosum laminae terminalis, paraventricular nucleus, and medial preoptic nucleus were markedly inhibited, and ACE and AT₁ receptor densities in the heart increased less (6-fold in the infarct scar). In kidneys, decreases in ACE and AT₁ receptor binding were absent after treatment with Fab fragments. These results demonstrate that ACE and AT₁ receptor binding densities increase not only in the heart but also in relevant areas of the brain of rats after MI. Brain OLC appears to play a major role in activation of brain RAS in rats after MI and, to a modest degree, in activation of the cardiac RAS.

renin-angiotensin system; autoradiography; heart failure

This article has been cited by other articles:

				S.-G. Wei, Y. Yu, Z.-H. Zhang, R. M. Weiss, and R. B. Felder Mitogen-Activated Protein Kinases Mediate Upregulation of Hypothalamic Angiotensin II Type 1 Receptors in Heart Failure Rats Hypertension, October 1, 2008; 52(4): 679 - 686. [Abstract] [Full Text] [PDF]

				Y.-M. Kang, Y. Ma, C. Elks, J.-P. Zheng, Z.-M. Yang, and J. Francis Cross-talk between cytokines and renin-angiotensin in hypothalamic paraventricular nucleus in heart failure: role of nuclear factor-{kappa}B Cardiovasc Res, September 1, 2008; 79(4): 671 - 678. [Abstract] [Full Text] [PDF]

				Y.-M. Kang, Z.-H. Zhang, B. Xue, R. M. Weiss, and R. B. Felder Inhibition of brain proinflammatory cytokine synthesis reduces hypothalamic excitation in rats with ischemia-induced heart failure Am J Physiol Heart Circ Physiol, July 1, 2008; 295(1): H227 - H236. [Abstract] [Full Text] [PDF]

				Y. Yu, S.-G. Wei, Z.-H. Zhang, E. Gomez-Sanchez, R. M. Weiss, and R. B. Felder Does Aldosterone Upregulate the Brain Renin-Angiotensin System in Rats With Heart Failure? Hypertension, March 1, 2008; 51(3): 727 - 733. [Abstract] [Full Text] [PDF]

				B. S. Huang, W. J. Cheung, H. Wang, J. Tan, R. A. White, and F. H. H. Leenen Activation of brain renin-angiotensin-aldosterone system by central sodium in Wistar rats Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1109 - H1117. [Abstract] [Full Text] [PDF]

				W. J. Cheung, M.-A. H. Kent, E. El-Shahat, H. Wang, J. Tan, R. White, and F. H. H. Leenen Central and peripheral renin-angiotensin systems in ouabain-induced hypertension Am J Physiol Heart Circ Physiol, August 1, 2006; 291(2): H624 - H630. [Abstract] [Full Text] [PDF]

				S. A. Dean, J. Tan, R. White, E. R. O'Brien, and F. H. H. Leenen Regulation of components of the brain and cardiac renin-angiotensin systems by 17beta-estradiol after myocardial infarction in female rats Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2006; 291(1): R155 - R162. [Abstract] [Full Text] [PDF]

				Z.-H. Zhang, Y.-M. Kang, Y. Yu, S.-G. Wei, T. J. Schmidt, A. K. Johnson, and R. B. Felder 11{beta}-Hydroxysteroid Dehydrogenase Type 2 Activity in Hypothalamic Paraventricular Nucleus Modulates Sympathetic Excitation Hypertension, July 1, 2006; 48(1): 127 - 133. [Abstract] [Full Text] [PDF]

				E. A. Jankowska, P. Ponikowski, M. F. Piepoli, W. Banasiak, S. D. Anker, and P. A. Poole-Wilson Autonomic imbalance and immune activation in chronic heart failure - Pathophysiological links Cardiovasc Res, June 1, 2006; 70(3): 434 - 445. [Abstract] [Full Text] [PDF]

				B. S. Huang and F. H. H. Leenen Blockade of brain mineralocorticoid receptors or Na+ channels prevents sympathetic hyperactivity and improves cardiac function in rats post-MI Am J Physiol Heart Circ Physiol, May 1, 2005; 288(5): H2491 - H2497. [Abstract] [Full Text] [PDF]

				S. A. Dean, J. Tan, E. R. O'Brien, and F. H. H. Leenen 17{beta}-Estradiol downregulates tissue angiotensin-converting enzyme and ANG II type 1 receptor in female rats Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2005; 288(3): R759 - R766. [Abstract] [Full Text] [PDF]

				J. Francis, S.-G. Wei, R. M. Weiss, and R. B. Felder Brain angiotensin-converting enzyme activity and autonomic regulation in heart failure Am J Physiol Heart Circ Physiol, November 1, 2004; 287(5): H2138 - H2146. [Abstract] [Full Text] [PDF]

				L. Gao, W. Wang, Y.-L. Li, H. D. Schultz, D. Liu, K. G. Cornish, and I. H. Zucker Superoxide Mediates Sympathoexcitation in Heart Failure: Roles of Angiotensin II and NAD(P)H Oxidase Circ. Res., October 29, 2004; 95(9): 937 - 944. [Abstract] [Full Text] [PDF]

				G.-Q. Zhu, L. Gao, Y. Li, K. P. Patel, I. H. Zucker, and W. Wang AT1 receptor mRNA antisense normalizes enhanced cardiac sympathetic afferent reflex in rats with chronic heart failure Am J Physiol Heart Circ Physiol, October 1, 2004; 287(4): H1828 - H1835. [Abstract] [Full Text] [PDF]