|
|
||||||||
1 Department of Physiology, University of Auckland, Auckland, New Zealand; and 2 Circulatory Control Laboratory, Department of Physiology, Monash University, Melbourne, Victoria 3168, Australia
To test whether renal sympathetic nerve activity (RSNA) can differentially regulate blood flow in the renal medulla (MBF) and cortex (CBF) of pentobarbital sodium-anesthetized rabbits, we electrically stimulated the renal nerves while recording total renal blood flow (RBF), CBF, and MBF. Three stimulation sequences were applied 1) varying amplitude (0.5-8 V), 2) varying frequency (0.5-8 Hz), and 3) a modulated sinusoidal pattern of varying frequency (0.04-0.72 Hz). Increasing amplitude or frequency of stimulation progressively decreased all flow variables. RBF and CBF responded similarly, but MBF responded less. For example, 0.5-V stimulation decreased CBF by 20 ± 9%, but MBF fell by only 4 ± 6%. The amplitude of oscillations in all flow variables was progressively reduced as the frequency of sinusoidal stimulation was increased. An increased amplitude of oscillation was observed at 0.12 and 0.32 Hz in MBF and to a lesser extent RBF, but not CBF. MBF therefore appears to be less sensitive than CBF to the magnitude of RSNA, but it is more able to respond to these higher frequencies of neural stimulation.
anesthetized rabbit; cortical blood flow; electrical stimulation; medullary blood flow; renal nerves
This article has been cited by other articles:
![]() |
R. G. Evans, S. L. Burke, G. W. Lambert, and G. A. Head Renal responses to acute reflex activation of renal sympathetic nerve activity and renal denervation in secondary hypertension Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2007; 293(3): R1247 - R1256. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. L. Burke, G. A. Head, G. W. Lambert, and R. G. Evans Renal Sympathetic Neuroeffector Function in Renovascular and Angiotensin II-Dependent Hypertension in Rabbits Hypertension, April 1, 2007; 49(4): 932 - 938. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. W. Rajapakse, G. A. Eppel, R. E. Widdop, and R. G. Evans ANG II type 2 receptors and neural control of intrarenal blood flow Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2006; 291(6): R1669 - R1676. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. C. Malpas, R. Ramchandra, S.-J. Guild, D. M. Budgett, and C. J. Barrett Baroreflex mechanisms regulating mean level of SNA differ from those regulating the timing and entrainment of the sympathetic discharges in rabbits Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2006; 291(2): R400 - R409. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. M. O'Connor, M. M. Kett, W. P. Anderson, and R. G. Evans Renal medullary tissue oxygenation is dependent on both cortical and medullary blood flow Am J Physiol Renal Physiol, March 1, 2006; 290(3): F688 - F694. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. A. Eppel, S. E. Luff, K. M. Denton, and R. G. Evans Type 1 neuropeptide Y receptors and {alpha}1-adrenoceptors in the neural control of regional renal perfusion Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2006; 290(2): R331 - R340. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. W. Rajapakse, A. K. Sampson, G. A. Eppel, and R. G. Evans Angiotensin II and nitric oxide in neural control of intrarenal blood flow Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2005; 289(3): R745 - R754. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. W. Rajapakse, R. J. Roman, J. R. Falck, J. J. Oliver, and R. G. Evans Modulation of V1-receptor-mediated renal vasoconstriction by epoxyeicosatrienoic acids Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2004; 287(1): R181 - R187. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. C. Malpas What sets the long-term level of sympathetic nerve activity: is there a role for arterial baroreceptors? Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2004; 286(1): R1 - R12. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Malpas, S.-J. Guild, R. Evans, and G. F. DiBona Responsiveness of the Renal Vasculature: Relating Electrical Stimulation to Endogenous Nerve Activity Is Problematic Am J Physiol Renal Physiol, March 1, 2003; 284(3): F594 - F596. [Full Text] [PDF] |
||||
![]() |
D. L. Mattson Importance of the renal medullary circulation in the control of sodium excretion and blood pressure Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2003; 284(1): R13 - R27. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. A. Eppel, G. Bergstrom, W. P. Anderson, and R. G. Evans Autoregulation of renal medullary blood flow in rabbits Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2003; 284(1): R233 - R244. [Abstract] [Full Text] [PDF] |
||||
![]() |
S.-J. Guild, G. A. Eppel, S. C. Malpas, N. W. Rajapakse, A. Stewart, and R. G. Evans Regional responsiveness of renal perfusion to activation of the renal nerves Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2002; 283(5): R1177 - R1186. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Grisk and H. M. Stauss Frequency modulation of mesenteric and renal vascular resistance Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2002; 282(5): R1468 - R1476. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Ramchandra, C. J. Barrett, S.-J. Guild, and S. C. Malpas Is the chronically denervated kidney supersensitive to catecholamines? Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2002; 282(2): R603 - R610. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. M. Denton, A. Shweta, and W. P. Anderson Preglomerular and Postglomerular Resistance Responses to Different Levels of Sympathetic Activation by Hypoxia J. Am. Soc. Nephrol., January 1, 2002; 13(1): 27 - 34. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. L. Leonard, S. C. Malpas, K. M. Denton, A. C. Madden, and R. G. Evans Differential control of intrarenal blood flow during reflex increases in sympathetic nerve activity Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2001; 280(1): R62 - R68. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Nishiyama, S. Kimura, T. Fukui, M. Rahman, H. Yoneyama, H. Kosaka, and Y. Abe Blood flow-dependent changes in renal interstitial guanosine 3',5'-cyclic monophosphate in rabbits Am J Physiol Renal Physiol, February 1, 2002; 282(2): F238 - F244. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |