QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, June 16, 2004, 24(24):5549-5559; doi:10.1523/JNEUROSCI.2719-03.2004

This Article Full Text Full Text (PDF) Submit an eLetter 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 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 Web of Science (13) Citing Articles via Google Scholar Google Scholar Articles by Morinville, A. Articles by Beaudet, A. Search for Related Content PubMed PubMed Citation Articles by Morinville, A. Articles by Beaudet, A.

 Previous Article  |  Next Article 

Cellular/Molecular
Morphine-Induced Changes in Opioid Receptor Trafficking Are Linked to Somatosensory Processing in the Rat Spinal Cord

Anne Morinville,^1,2 Catherine M. Cahill,¹ Haneen Aibak,¹ Vladimir V. Rymar,¹ Amynah Pradhan,² Cyrla Hoffert,³ Françoise Mennicken,³ Thomas Stroh,² Abbas F. Sadikot,¹ Dajan O'Donnell,³ Paul B. S. Clarke,² Brian Collier,² James L. Henry,⁴ Jean-Pierre Vincent,⁵ and Alain Beaudet¹

¹Montreal Neurological Institute, McGill University, Montreal, Québec, Canada H3A 2B4, ²Department of Pharmacology and Therapeutics, McGill University, Montreal, Québec, Canada H3G 1Y6, ³Department of Molecular Sciences, AstraZeneca R&D Montreal, Montreal, Québec, Canada H4S 1Z9, ⁴Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada N6A 5C1, and ⁵Institut de Pharmacologie Moléculaire et Cellulaire, Centre National de la Recherche Scientifique, Université de Nice, 06560 Valbonne, France

An in vivo fluorescent deltorphin (Fluo-DLT) internalization assay was used to assess the distribution and regulation of pharmacologically available opioid receptors (ORs) in the rat lumbar (L4-5) spinal cord. Under basal conditions, intrathecal injection of Fluo-DLT resulted in the labeling of numerous OR-internalizing neurons throughout dorsal and ventral horns. The distribution and number of Fluo-DLT-labeled perikaryal profiles were consistent with that of OR-expressing neurons, as revealed by in situ hybridization and immunohistochemistry, suggesting that a large proportion of these cells was responsive to intrathecally administered OR agonists. Pretreatment of rats with morphine for 48 hr resulted in a selective increase in Fluo-DLT-labeled perikaryal profiles within the dorsal horn. These changes were not accompanied by corresponding augmentations in either OR mRNA or ¹²⁵I-deltorphin-II binding levels, suggesting that they were attributable to higher densities of cell surface OR available for internalization rather than to enhanced production of the receptor. Unilateral dorsal rhizotomy also resulted in increased Fluo-DLT internalization in the ipsilateral dorsal horn when compared with the side contralateral to the deafferentation or to non-deafferented controls, suggesting that OR trafficking in dorsal horn neurons may be regulated by afferent inputs. Furthermore, morphine treatment no longer increased Fluo-DLT internalization on either side of the spinal cord after unilateral dorsal rhizotomy, indicating that µOR-induced changes in the cell surface availability of OR depend on the integrity of primary afferent inputs. Together, these results suggest that regulation of OR responsiveness through µOR activation in this region is linked to somatosensory information processing.

Key words: opiate; morphine; internalization; fluorescence microscopy; targeting; narcotic; intrathecal; dorsal rhizotomy

---

Received May 29, 2003; revised April 22, 2004; accepted April 26, 2004.

This article has been cited by other articles:

				B. Bie, W. Zhu, and Z. Z. Pan Rewarding Morphine-Induced Synaptic Function of {delta}-Opioid Receptors on Central Glutamate Synapses J. Pharmacol. Exp. Ther., April 1, 2009; 329(1): 290 - 296. [Abstract] [Full Text] [PDF]

				W.-Y. Xie, Y. He, Y.-R. Yang, Y.-F. Li, K. Kang, B.-M. Xing, and Y. Wang Disruption of Cdk5-Associated Phosphorylation of Residue Threonine-161 of the {delta}-Opioid Receptor: Impaired Receptor Function and Attenuated Morphine Antinociceptive Tolerance J. Neurosci., March 18, 2009; 29(11): 3551 - 3564. [Abstract] [Full Text] [PDF]

				L. Gendron, A. L. Lucido, F. Mennicken, D. O'Donnell, J.-P. Vincent, T. Stroh, and A. Beaudet Morphine and Pain-Related Stimuli Enhance Cell Surface Availability of Somatic {delta}-Opioid Receptors in Rat Dorsal Root Ganglia J. Neurosci., January 18, 2006; 26(3): 953 - 962. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help