AJP - Regulatory, Integrative and Comparative Physiology, Vol 260, Issue 1 232-R239, Copyright © 1991 by American Physiological Society

ARTICLES

Inhibitory renorenal reflexes: a role for substance P or other capsaicin-sensitive neurons

U. C. Kopp and L. A. Smith
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City.

In anesthetized rats, we examined whether inhibitory renorenal reflex responses to renal pelvic mechanoreceptor (MR) and chemoreceptor (CR) stimulation were mediated by substance P (SP)-containing neurons. Capsaicin (0.5 ng to 5 micrograms) injected into the renal pelvis increased afferent renal nerve activity (ARNA) dose dependently, from 60 +/- 19 to 333 +/- 105%. For a given ARNA response, a 100-fold higher dose was required when capsaicin was injected into the renal interstitium compared with the renal pelvis. Renal pelvic administration of SP (25 ng) increased ipsilateral ARNA by 126 +/- 34% and contralateral urine flow rate and urinary sodium excretion by 21 +/- 4 and 28 +/- 7%, respectively, a response similar to that produced by renal MR and CR stimulation. Mean arterial pressure was unaffected. Ipsilateral renal denervation abolished the contralateral diuresis and natriuresis produced by SP. In rats treated with capsaicin (950 mg/kg subcutaneously over 1 wk) to deplete sensory neurons of SP, renal MR and CR stimulation failed to elicit a renorenal reflex response. The data suggest that the renorenal reflex responses to renal MR and CR stimulation are mediated at least, in part, by SP neurons or other sensory neurons susceptible to depletion by capsaicin.

This article has been cited by other articles:

				C. Xie, J. R. Sachs, and D. H. Wang Interdependent Regulation of Afferent Renal Nerve Activity and Renal Function: Role of Transient Receptor Potential Vanilloid Type 1, Neurokinin 1, and Calcitonin Gene-Related Peptide Receptors J. Pharmacol. Exp. Ther., June 1, 2008; 325(3): 751 - 757. [Abstract] [Full Text] [PDF]

				M.-C. Ma, H.-S. Huang, M.-S. Wu, C.-T. Chien, and C.-F. Chen Impaired Renal Sensory Responses after Renal Ischemia in the Rat J. Am. Soc. Nephrol., July 1, 2002; 13(7): 1872 - 1883. [Abstract] [Full Text] [PDF]

				M.-C. Ma, H.-S. Huang, C.-T. Chien, M.-S. Wu, and C.-F. Chen Temporal decrease in renal sensory responses in rats after chronic ligation of the bile duct Am J Physiol Renal Physiol, July 1, 2002; 283(1): F164 - F172. [Abstract] [Full Text] [PDF]

				U. C. Kopp, M. Z. Cicha, and L. A. Smith PGE2 increases release of substance P from renal sensory nerves by activating the cAMP-PKA transduction cascade Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2002; 282(6): R1618 - R1627. [Abstract] [Full Text] [PDF]

				M.-C. Ma, H.-S. Huang, and C.-F. Chen Impaired Renal Sensory Responses after Unilateral Ureteral Obstruction in the Rat J. Am. Soc. Nephrol., April 1, 2002; 13(4): 1008 - 1016. [Abstract] [Full Text] [PDF]

				U. C. Kopp, M. Z. Cicha, and L. A. Smith Endogenous angiotensin modulates PGE2-mediated release of substance P from renal mechanosensory nerve fibers Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2002; 282(1): R19 - R30. [Abstract] [Full Text] [PDF]

				U. C. Kopp, M. Z. Cicha, L. A. Smith, and T. Hokfelt Nitric oxide modulates renal sensory nerve fibers by mechanisms related to substance P receptor activation Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2001; 281(1): R279 - R290. [Abstract] [Full Text] [PDF]

				U. C. Kopp and M. Z. Cicha PGE2 increases substance P release from renal pelvic sensory nerves via activation of N-type calcium channels Am J Physiol Regulatory Integrative Comp Physiol, May 1, 1999; 276(5): R1241 - R1248. [Abstract] [Full Text] [PDF]

				G. F. DiBona, S. Y. Jones, and U. C. Kopp Renal Mechanoreceptor Dysfunction : An Intermediate Phenotype in Spontaneously Hypertensive Rats Hypertension, January 1, 1999; 33(1): 472 - 475. [Abstract] [Full Text] [PDF]

				J. R. Gontijo, L. A. Smith, and U. C. Kopp CGRP Activates Renal Pelvic Substance P Receptors by Retarding Substance P Metabolism Hypertension, January 1, 1999; 33(1): 493 - 498. [Abstract] [Full Text] [PDF]

				P. Santicioli and C. A. Maggi Myogenic and Neurogenic Factors in the Control of Pyeloureteral Motility and Ureteral Peristalsis Pharmacol. Rev., December 1, 1998; 50(4): 683 - 722. [Abstract] [Full Text] [PDF]

				U. C. Kopp, K. Matsushita, R. D. Sigmund, L. A. Smith, S. Watanabe, and J. B. Stokes Amiloride-sensitive Na+ channels in pelvic uroepithelium involved in renal sensory receptor activation Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1998; 275(6): R1780 - R1792. [Abstract] [Full Text] [PDF]

				U. C. Kopp, M. Z. Cicha, D. M. Farley, L. A. Smith, and B. S. Dixon Renal Substance P–Containing Neurons and Substance P Receptors Impaired in Hypertension Hypertension, March 1, 1998; 31(3): 815 - 822. [Abstract] [Full Text] [PDF]