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

This Article Full Text Full Text (PDF) All Versions of this Article: mol.104.004614v1 67/3/965    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Similar articles in this journal 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 Google Scholar Google Scholar Articles by Mollereau, C. Articles by Roumy, M. Search for Related Content PubMed PubMed Citation Articles by Mollereau, C. Articles by Roumy, M.

ORIGINAL ARTICLE

Neuropeptide FF (NPFF) Analogs Functionally Antagonize Opioid Activities in NPFF₂ Receptor-Transfected SH-SY5Y Neuroblastoma Cells

Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Unité Mixte Recherche 5089, Toulouse, France

Abstract

To elucidate the mechanism of the cellular antiopioid activity of neuropeptide FF (NPFF), we have transfected the SH-SY5Y neuroblastoma cell line, which expresses µ-and -opioid receptors, with the human NPFF₂ receptor. The selected clone, SH₂-D9, expressed high-affinity NPFF₂ receptors in the same range order as µ- and -opioid receptors (100–300 fmol/mg of protein). The NPFF analog [D-Tyr¹, (NMe)Phe³]NPFF (1DMe) did not modify the binding parameters of the µ- and -specific agonists [D-Ala²,N-Me-Phe⁴,Gly⁵-ol]-enkephalin and deltorphin-I, respectively. 1DMe dose dependently inhibited 75 to 80% of the cAMP production stimulated by forskolin. Preincubation with 1DMe halved the maximal inhibition of N-type Ca²⁺ channels by opioid agonists. In the presence of carbachol, acting on muscarinic receptors to release Ca²⁺ from the intracellular stores, deltorphin-I and 1DMe enhanced this release. Preincubation with 1DMe reduced the maximal effect of deltorphin-I by 40%, demonstrating an antiopioid effect in this experimental model for the first time. By using peptides corresponding to the carboxyl terminus of the _i1,2, _i3, _o, and _s subunits of G proteins, which specifically uncouple receptors from G proteins, we demonstrated that µ-opioid and NPFF₂ receptors couple to the four subunits assayed. The Ca²⁺ release from the intracellular stores by 1DMe resulted from the coupling of NPFF₂ receptors with G_o and G_i1,2, whereas the coupling with G_s reduced the antiopioid effect of 1DMe in the modulation of N-type channels. This SH₂-D9 cell line now provides the opportunity to study the interaction between both receptors.

Address correspondence to: Dr. Michel Roumy, Institut de Pharmacologie et de Biologie Structurale, CNRS, UMR 5089, 205 route de Narbonne, 31077 Toulouse cedex 04, France. E-mail: michel.roumy{at}ipbs.fr

This article has been cited by other articles:

				M. Roumy, C. Lorenzo, S. Mazeres, S. Bouchet, J.-M. Zajac, and C. Mollereau Physical Association between Neuropeptide FF and {micro}-Opioid Receptors as a Possible Molecular Basis for Anti-opioid Activity J. Biol. Chem., March 16, 2007; 282(11): 8332 - 8342. [Abstract] [Full Text] [PDF]