|
|
||||||||
Hypertension Center, Division of Surgical Sciences, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1032
The object of the current study was to determine if ANG II acts at type 1 (AT1) or type 2 (AT2) receptors in the nucleus of the solitary tract (NTS) to reduce baroreceptor reflex control of renal sympathetic nerve activity (RSNA) and heart rate (HR). Experiments were carried out in urethan-anesthetized Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR). Reflex changes in RSNA and HR were elicited by intravenous infusion of either phenylephrine or sodium nitroprusside before and after bilateral microinjection of CV-11974 (AT1 receptor antagonist, 10 pmol), PD-123319 (AT2 receptor antagonist, 100 pmol), or artificial cerebrospinal fluid (aCSF, 50 nl) in the NTS. Mean arterial pressure (MAP)-RSNA and MAP-HR data were fit to logistic functions to analyze the baroreceptor reflex. Baroreceptor reflex sensitivities for RSNA and HR were attenuated in SHR compared with those in WKY rats. Bilateral injection of CV-11974, PD-123319, or aCSF in the NTS of either strain had no effect on baseline arterial pressure, HR, or RSNA. However, CV-11974 injected in the NTS increased significantly (P < 0.01) the sensitivities for baroreceptor reflex control of RSNA and HR in SHR and WKY rats. Neither PD-123319 nor aCSF altered baroreceptor reflex control of RSNA and HR in either SHR or WKY rats. These results demonstrate that endogenous ANG II acts at AT1 receptors of the NTS to attenuate the baroreceptor reflex in SHR as well as in WKY rats.
angiotensin receptors; genetic hypertension; sympathetic nervous system; renal sympathetic nerve activity; spontaneously hypertensive rat
This article has been cited by other articles:
![]() |
W.-Z. Wang, L. Gao, H.-J. Wang, I. H. Zucker, and W. Wang Interaction between cardiac sympathetic afferent reflex and chemoreflex is mediated by the NTS AT1 receptors in heart failure Am J Physiol Heart Circ Physiol, September 1, 2008; 295(3): H1216 - H1226. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Yao, C. Sumners, S. T. O'Rourke, and C. Sun Angiotensin II increases GABAB receptor expression in nucleus tractus solitarii of rats Am J Physiol Heart Circ Physiol, June 1, 2008; 294(6): H2712 - H2720. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. S. P. Tan, S. Killinger, J. Horiuchi, and R. A. L. Dampney Baroreceptor reflex modulation by circulating angiotensin II is mediated by AT1 receptors in the nucleus tractus solitarius Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2007; 293(6): R2267 - R2278. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. W. Polson, R. A. L. Dampney, P. Boscan, A. E. Pickering, and J. F. R. Paton Differential baroreflex control of sympathetic drive by angiotensin II in the nucleus tractus solitarii Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2007; 293(5): R1954 - R1960. [Abstract] [Full Text] [PDF] |
||||
![]() |
W.-Z. Wang, L. Gao, Y.-X. Pan, I. H. Zucker, and W. Wang AT1 receptors in the nucleus tractus solitarii mediate the interaction between the baroreflex and the cardiac sympathetic afferent reflex in anesthetized rats Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2007; 292(3): R1137 - R1145. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Sakima, D. B. Averill, S. O. Kasper, L. Jackson, D. Ganten, C. M. Ferrario, P. E. Gallagher, and D. I. Diz Baroreceptor reflex regulation in anesthetized transgenic rats with low glia-derived angiotensinogen Am J Physiol Heart Circ Physiol, March 1, 2007; 292(3): H1412 - H1419. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. D. Rowe, J. A. Schwartz, L. L. Lomax, and M. M. Knuepfer Central angiotensin II receptors mediate hemodynamic response variability to stressors Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2006; 291(3): R719 - R727. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Sakai, M. W. Chapleau, S. Morimoto, M. D. Cassell, and C. D. Sigmund Differential modulation of baroreflex control of heart rate by neuron- vs. glia-derived angiotensin II Physiol Genomics, December 15, 2004; 20(1): 66 - 72. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. ANTUNES-RODRIGUES, M. DE CASTRO, L. L. K. ELIAS, M. M. VALENCA, and S. M. McCANN Neuroendocrine Control of Body Fluid Metabolism Physiol Rev, January 1, 2004; 84(1): 169 - 208. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. L. Barnes, D. M. DeWeese, and M. C. Andresen Angiotensin potentiates excitatory sensory synaptic transmission to medial solitary tract nucleus neurons Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2003; 284(5): R1340 - R1353. [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] |
||||
![]() |
D. A. Scheuer and A. G. Bechtold Glucocorticoids potentiate central actions of angiotensin to increase arterial pressure Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2001; 280(6): R1719 - R1726. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. P. O'Hagan, K. A. Skogg, and J. B. Stevenson AT1 receptor block does not affect arterial baroreflex during pregnancy in rabbits Am J Physiol Heart Circ Physiol, May 1, 2001; 280(5): H1996 - H2005. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. H. Worck, D. Staahltoft, T. E. N. Jonassen, E. Frandsen, H. Ibsen, and J. S. Petersen Brain angiotensin receptors and sympathoadrenal regulation during insulin-induced hypoglycemia Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2001; 280(4): R1162 - R1168. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |