|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Internal Medicine, University of California, Davis, Davis, California, United States
2 Div. of Cardiovascular Medicine, University of California, Davis, Davis, California, United States
* To whom correspondence should be addressed. E-mail: mpkaufman{at}ucdavis.edu.
The renal vasoconstriction induced by the sympathetic outflow during exercise serves to direct blood flow from the kidney towards the exercising muscles. The renal circulation seems to be particularly important in this regard because it receives a substantial part of the cardiac output, which in resting humans has been estimated to be 20 %. The role played by group III mechanoreceptors in causing the reflex renal sympathetic response to static contraction remains an open question. To shed some light on this question, we recorded the renal sympathetic nerve responses to static contraction before and after injecting gadolinium into the arterial supply of the statically contracting triceps surae muscles of both decerebrated unanesthetized and chloralose anesthetized cats. Gadolinium has been shown to be a selective blocker of mechanogated channels in thin fiber muscle afferents, which comprise the afferent arm of the exercise pressor reflex arc. In both decerebrated (n=15) and chloralose anesthetized (n=12) cats, we found that gadolinium (10mM; 1 ml) significantly attenuated the renal sympathetic nerve and pressor responses to static contraction (60 seconds) after a latent period of 60 minutes; both responses recovered after a latent period of 120 minutes. We conclude that thin fiber mechanoreceptors supplying contracting muscle are capable of playing a role in causing some the renal vasoconstriction evoked by the exercise pressor reflex.
This article has been cited by other articles:
![]() |
A. K. Leal, M. A. Williams, M. G. Garry, J. H. Mitchell, and S. A. Smith Evidence for functional alterations in the skeletal muscle mechanoreflex and metaboreflex in hypertensive rats Am J Physiol Heart Circ Physiol, October 1, 2008; 295(4): H1429 - H1438. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. McCord, S. G. Hayes, and M. P. Kaufman Acid-sensing ion and epithelial sodium channels do not contribute to the mechanoreceptor component of the exercise pressor reflex Am J Physiol Heart Circ Physiol, September 1, 2008; 295(3): H1017 - H1024. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Matsukawa and T. Nakamoto Muscle mechanosensitive reflex is suppressed in the conscious condition: effect of anesthesia J Appl Physiol, January 1, 2008; 104(1): 82 - 87. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. T. Kuipers, C. L. Sauder, M. L. Kearney, and C. A. Ray Changes in forearm muscle temperature alter renal vascular responses to isometric handgrip Am J Physiol Heart Circ Physiol, December 1, 2007; 293(6): H3432 - H3439. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. E. Kindig, S. G. Hayes, and M. P. Kaufman Blockade of purinergic 2 receptors attenuates the mechanoreceptor component of the exercise pressor reflex Am J Physiol Heart Circ Physiol, November 1, 2007; 293(5): H2995 - H3000. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Koba, J. Xing, L. I. Sinoway, and J. Li Differential sympathetic outflow elicited by active muscle in rats Am J Physiol Heart Circ Physiol, October 1, 2007; 293(4): H2335 - H2343. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |