HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Free Full Text (PDF) Free All Versions of this Article: 98/6/2056    most recent 01282.2004v1 Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (10) Citing Articles via Google Scholar Google Scholar Articles by Crisostomo, M. M. Articles by Longhurst, J. C. Search for Related Content PubMed PubMed Citation Articles by Crisostomo, M. M. Articles by Longhurst, J. C.

Nociceptin in rVLM mediates electroacupuncture inhibition of cardiovascular reflex excitatory response in rats

Department of Medicine, Susan Samueli Center for Integrative Medicine, College of Medicine, University of California, Irvine, CA 92697-4075

Submitted 15 November 2004 ; accepted in final form 12 January 2005

Electroacupuncture (EA) at Neiguan-Jianshi acupoints through an opioid mechanism inhibits the cardiovascular pressor response induced by mechanical stimulation of the stomach. Because nociceptin also may regulate cardiovascular activity through its action in the brain stem, we hypothesized that this neuromodulator serves a role in the EA-related inhibitory effect. Blood pressure in ventilated male Sprague-Dawley rats (400–600 g) anesthetized by ketamine and -chloralose was measured during balloon inflation of the stomach. Gastric distension with 6–8 ml of air induced consistent pressor reflexes of 26 ± 1 mmHg that could be repeated every 10 min for 100 min. When nociceptin (10 nM) was microinjected into the rostral ventrolateral medulla (rVLM), the pressor response induced by gastric distension was inhibited by 68 ± 6%. Thirty minutes of EA also decreased the reflex response by 75 ± 11%; microinjection of saline into the rVLM did not alter the inhibitory effect of EA. In contrast, microinjection of a nociceptin receptor antagonist into the rVLM promptly reversed the EA response. Pretreatment with the opioid receptor antagonist naloxone did not influence the EA-like inhibitory effect of nociceptin on the distension-induced pressor reflex (22 ± 1 to 8 ± 2 mmHg). Furthermore, a µ-opioid receptor agonist microinjected into the rVLM after microinjection of a nociceptin receptor antagonist during EA promptly reversed the nociceptin receptor antagonist-related inhibition of the EA effect. Thus, in addition to the classical opioid system, nociceptin, through opioid receptor-like-1 receptor stimulation in the rVLM, participates in the modulatory influence of EA on reflex-induced increases in blood pressure.

opioids; gastric distension; somatic afferent

This article has been cited by other articles:

				S. C. Tjen-A-Looi, P. Li, and J. C. Longhurst Role of medullary GABA, opioids, and nociceptin in prolonged inhibition of cardiovascular sympathoexcitatory reflexes during electroacupuncture in cats Am J Physiol Heart Circ Physiol, December 1, 2007; 293(6): H3627 - H3635. [Abstract] [Full Text] [PDF]

				C. Shang Prospective Tests on Biological Models of Acupuncture Evid. Based Complement. Altern. Med., November 21, 2007; (2007) nem122v1. [Abstract] [Full Text] [PDF]

				H. L. Lujan, V. J. Kramer, and S. E. DiCarlo Electroacupuncture decreases the susceptibility to ventricular tachycardia in conscious rats by reducing cardiac metabolic demand Am J Physiol Heart Circ Physiol, May 1, 2007; 292(5): H2550 - H2555. [Abstract] [Full Text] [PDF]

				J. C. Longhurst Electroacupuncture treatment of arrhythmias in myocardial ischemia Am J Physiol Heart Circ Physiol, May 1, 2007; 292(5): H2032 - H2034. [Full Text] [PDF]

				W. Zhou, L.-W. Fu, Z.-L. Guo, and J. C. Longhurst Role of glutamate in the rostral ventrolateral medulla in acupuncture-related modulation of visceral reflex sympathoexcitation Am J Physiol Heart Circ Physiol, April 1, 2007; 292(4): H1868 - H1875. [Abstract] [Full Text] [PDF]

				W. Zhou, L.-W. Fu, S. C. Tjen-A-Looi, Z.-l. Guo, and J. C. Longhurst Role of glutamate in a visceral sympathoexcitatory reflex in rostral ventrolateral medulla of cats Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1309 - H1318. [Abstract] [Full Text] [PDF]

				S. C. Tjen-A-Looi, P. Li, and J. C. Longhurst Midbrain vlPAG inhibits rVLM cardiovascular sympathoexcitatory responses during electroacupuncture Am J Physiol Heart Circ Physiol, June 1, 2006; 290(6): H2543 - H2553. [Abstract] [Full Text] [PDF]

				W. Zhou (Yi Syuu), I. Hsiao, V. W. H. Lin, and J. C. Longhurst Modulation of cardiovascular excitatory responses in rats by transcutaneous magnetic stimulation: role of the spinal cord J Appl Physiol, March 1, 2006; 100(3): 926 - 932. [Abstract] [Full Text] [PDF]

				W. Zhou (Yi Syuu), S. C. Tjen-A-Looi, and J. C. Longhurst Brain stem mechanisms underlying acupuncture modality-related modulation of cardiovascular responses in rats J Appl Physiol, September 1, 2005; 99(3): 851 - 860. [Abstract] [Full Text] [PDF]