|
|
||||||||
University of Mississippi Medical Center, Department of Physiology and Biophysics, Jackson, Mississippi 39216-4505
The purpose of this study was to elucidate the role of circulating ANG II in mediating changes in systemic and renal hemodynamics, salt and water balance, and neurohormonal activation during the early progression of heart failure. This objective was achieved by subjecting six dogs to 14 days of rapid ventricular pacing (240 beats/min) while fixing plasma ANG II concentration (by infusion of captopril + ANG II) either at approximately normal (days 1-8, 13-14) or at high physiological (days 9-12) levels. Salt and water retention occurred during the initial days of pacing before sodium and fluid balance was achieved by day 8. At this time, cardiac output and mean arterial pressure were reduced to ~55 and 75% of control, respectively; compared with cardiac output, reductions in renal blood flow were less pronounced. Although plasma ANG II concentration was maintained at approximately normal levels, there were sustained elevations in total peripheral resistance (to ~135% of control), filtration fraction (to ~118% of control), and plasma norepinephrine concentration (to 2-3 times control). During the subsequent high rate of ANG II infusion on days 9-12, there were no additional sustained long-term changes in either systemic or renal hemodynamics other than a further rise in right atrial pressure. However, high plasma levels of ANG II induced sustained antinatriuretic, sympathoexcitatory, and dipsogenic responses. Because these same long-term changes occur in association with activation of the renin-angiotensin system during the natural evolution of this disease, these results suggest that increased plasma levels of ANG II play a critical role in the spontaneous transition from compensated to decompensated heart failure.
sodium excretion; sympathetic nervous system; cardiac output; systemic and renal hemodynamics; drinking; atrial natriuretic peptide
This article has been cited by other articles:
![]() |
J. C. Sartori-Valinotti, R. Iliescu, L. L. Yanes, W. Dorsett-Martin, and J. F. Reckelhoff Sex Differences in the Pressor Response to Angiotensin II When the Endogenous Renin-Angiotensin System Is Blocked Hypertension, April 1, 2008; 51(4): 1170 - 1176. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Zheng, Y.-F. Li, I. H. Zucker, and K. P. Patel Exercise training improves renal excretory responses to acute volume expansion in rats with heart failure Am J Physiol Renal Physiol, December 1, 2006; 291(6): F1148 - F1156. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Yanes, D. Romero, R. Iliescu, V. E. Cucchiarelli, L. A. Fortepiani, F. Santacruz, W. Bell, H. Zhang, and J. F. Reckelhoff Systemic arterial pressure response to two weeks of Tempol therapy in SHR: involvement of NO, the RAS, and oxidative stress Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2005; 288(4): R903 - R908. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. A. Fortepiani, M. C. O. Ruiz, F. Passardi, M. D. Bentley, J. Garcia-Estan, E. L. Ritman, and J. C. Romero Effect of losartan on renal microvasculature during chronic inhibition of nitric oxide visualized by micro-CT Am J Physiol Renal Physiol, November 1, 2003; 285(5): F852 - F860. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. A. Fortepiani, L. Yanes, H. Zhang, L. C. Racusen, and J. F. Reckelhoff Role of Androgens in Mediating Renal Injury in Aging SHR Hypertension, November 1, 2003; 42(5): 952 - 955. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. B. Felder, J. Francis, Z.-H. Zhang, S.-G. Wei, R. M. Weiss, and A. K. Johnson Heart failure and the brain: new perspectives Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2003; 284(2): R259 - R276. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. E. Lohmeier Neurohumoral regulation of arterial pressure in hemorrhage and heart failure Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2002; 283(4): R810 - R814. [Full Text] [PDF] |
||||
![]() |
K.-D. Wagner, V. Essmann, K. Mydlak, M. Wirth, G. Gmehling, J. Bohlender, H. M. Stauss, J. Gunther, I. Schimke, and H. Scholz Decreased susceptibility of cardiac function to hypoxia-reoxygenation in renin-angiotensinogen transgenic rats Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2002; 283(1): R153 - R160. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Skott Renin Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2002; 282(4): R937 - R939. [Full Text] [PDF] |
||||
![]() |
T. E. Lohmeier, J. R. Lohmeier, J. F. Reckelhoff, and D. A. Hildebrandt Sustained influence of the renal nerves to attenuate sodium retention in angiotensin hypertension Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2001; 281(2): R434 - R443. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Shigematsu, Y. Hirooka, K. Eshima, M. Shihara, T. Tagawa, and A. Takeshita Endogenous angiotensin II in the NTS contributes to sympathetic activation in rats with aortocaval shunt Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2001; 280(6): R1665 - R1673. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. E. Lohmeier, J. R. Lohmeier, A. Haque, and D. A. Hildebrandt Baroreflexes prevent neurally induced sodium retention in angiotensin hypertension Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2000; 279(4): R1437 - R1448. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |