English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Effects of morphine withdrawal on μ-opioid receptor-stimulated guanylyl 5'-[γ-[35S]thio]-triphosphate autoradiography in rat brain

Kirschke, C., Schadrack, J., Zieglgänsberger, W., & Spanagel, R. (2002). Effects of morphine withdrawal on μ-opioid receptor-stimulated guanylyl 5'-[γ-[35S]thio]-triphosphate autoradiography in rat brain. European Journal of Pharmacology, 446(1-3), 43-51.

Item is

Basic

show hide
Genre: Journal Article
Alternative Title : Eur. J. Pharmacol.

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Kirschke, C1, Author
Schadrack, J1, Author
Zieglgänsberger, W1, Author
Spanagel, R1, Author
Affiliations:
1Max Planck Institute of Psychiatry, Max Planck Society, ou_1607137              

Content

show
hide
Free keywords: opiate withdrawal; morphine; opioid receptor; G-protein coupling; [S-35]GTP gamma S-binding
 Abstract: Abstinence from chronic morphine results in characteristic withdrawal symptoms in humans and experimental animals. Despite a large number of studies, the cellular mechanisms underlying opiate withdrawal symptoms are not clearly understood, in particular, the regulation of mu-opioid receptor function during this process. The present study investigated the It- opioid receptor-stimulated G-protein activity using guanylyl 5''-[gamma-[S-35]thio]-triphosphate ([S-35]-GTPgammaS) autoradiography. [S-35]-GTPgammaS binding was performed using coronal rat brain sections (20 mum) in the presence or absence of the mu-opioid selective agonist [D-Ala(2),N-MePhe(4)Gly(5)- ol] enkephalin (DAMGO). In experiment 1, rats (male, Sprague- Dawley) were injected every 12 h with increasing doses of morphine (5-100 mg/kg, s.c.) for 12 days; a separate group of rats which received saline injections served as control. Opiate withdrawal was induced by abstinence from morphine. Thirty-six hours after the last morphine injection, spontaneous withdrawal symptoms were assessed. Rats were then decapitated and brains rapidly removed. In experiment 2, withdrawal symptoms were precipitated with the opioid receptor antagonist naloxone (1 mg/kg). Brains were taken at 5, 10, 20 and 60 min after naloxone injection. In experiment 3, morphine dependence was induced by implantation of three morphine pellets (75 mg per pellet). After 7 days, withdrawal symptoms were precipitated by naloxone (1 mg/kg) and brains were removed 30 min after naloxone injection. [S-35]-GTPgammaS binding was measured in the locus coeruleus, nucleus parabrachialis, nucleus accumbens and central nucleus of amygdala. Although clear withdrawal symptoms were observed in all morphine-withdrawn rats, no significant changes in [S-35]-GTPgammaS binding were detected in animals undergoing withdrawal. The present lack of differences between morphine-withdrawn and control rats indicates that It-opioid receptor-stimulated G-protein activity is not modulated by chronic morphine administration and is not involved in the expression of opiate withdrawal. (C) 2002 Elsevier Science B.V. All rights re

Details

show
hide
Language(s): eng - English
 Dates: 2002-06-20
 Publication Status: Issued
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: eDoc: 4125
ISI: 000176791100006
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: European Journal of Pharmacology
  Alternative Title : Eur. J. Pharmacol.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 446 (1-3) Sequence Number: - Start / End Page: 43 - 51 Identifier: ISSN: 0014-2999