Background: Ethanol stimulates the dopaminergic mesoaccumbal pathway, which is thought to play a role in ethanol reinforcement. Mu (mu)-opioid (MOP) receptors modulate accumbal dopamine activity, but it is not clear whether MOP receptors are involved in the mechanism of ethanol-stimulated accumbal dopamine release.
Methods: We investigated the role that MOP receptors play in ethanol (2.0 g/kg)-stimulated accumbal dopamine release by using MOP receptor knockout mice (C57BL/6J-129SvEv and congenic C57BL/6J genotypes) along with blockade of MOP receptors with a mu1 selective antagonist (naloxonazine).
Results: Both gene deletion and pharmacological antagonism of the MOP receptor decreased ethanol-stimulated accumbal dopamine release compared with controls with female mice showing a larger effect in the C57BL/6J-129SvEv genotype. However, both male and female mice showed reduced ethanol-stimulated dopamine release in the congenic MOP receptor knockout mice (C57BL/6J). No differences in the time course of dialysate ethanol concentration were found in any of the experiments.
Conclusions: The data demonstrate the existence of a novel interaction between genotype and sex in the regulation of ethanol-stimulated mesolimbic dopamine release by the MOP receptor. This implies that a more complete understanding of the epistatic influences on the MOP receptor and mesolimbic dopamine function may provide more effective pharmacotherapeutic interventions in the treatment of alcoholism.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3076952 | PMC |
http://dx.doi.org/10.1016/j.biopsych.2006.11.016 | DOI Listing |
Alcohol Clin Exp Res (Hoboken)
December 2024
Integrated Program in Neuroscience, McGill University, Montreal, Quebec, Canada.
Background: Adolescent alcohol use is the norm, but only some develop a substance use disorder. The increased risk might reflect heightened mesocorticolimbic responses to reward-related cues but results published to date have been inconsistent.
Methods: Young social drinkers (age 18.
Commun Biol
December 2024
Robarts Research Institute, University of Western Ontario, London, ON, N6A 5B7, Canada.
The Pro/N-degron recognizing C-terminal to LisH (CTLH) complex is an E3 ligase of emerging interest in the developmental biology field and for targeted protein degradation (TPD) modalities. The human CTLH complex forms distinct supramolecular ring-shaped structures dependent on the multimerization of WDR26 or muskelin β-propeller proteins. Here, we find that, in HeLa cells, CTLH complex E3 ligase activity is dictated by an interplay between WDR26 and muskelin in tandem with muskelin autoregulation.
View Article and Find Full Text PDFBiochem Pharmacol
November 2024
Department of Biochemistry, Faculty of Medicine, Medical University of Lodz, Lodz, Poland. Electronic address:
The antinociceptive effect of the opioid drugs is achieved through activation of the µ-opioid receptor (MOP). The orthosteric and allosteric sites of opioid receptors may be modulated, orthosteric site by endogenous i.e.
View Article and Find Full Text PDFNeuropsychopharmacol Rep
March 2025
Addictive Substance Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
Although methamphetamine (METH) and other addictive substance use disorders are a major social problem worldwide, appropriate pharmacotherapies have not yet been discovered. Subtype-nonselective opioid receptor antagonists, such as naltrexone (NTX), have been reported to suppress METH addiction, but unclear are the opioid receptor subtypes that are involved in this beneficial effect. To clarify the role of μ-opioid receptors (MOPs), we examined effects of the novel nonpeptidic MOP-selective antagonist UD-030 on the acquisition and expression of METH-induced conditioned place preference (CPP) using behavioral tests in C57BL/6J mice.
View Article and Find Full Text PDFTransl Psychiatry
November 2024
Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska Institutet, Stockholm, SE-17176, Sweden.
Naltrexone (NTX), a homolog of the opiate antidote naloxone, is an orally active long-acting general opioid receptor antagonist used in the treatment of opiate dependence. NTX is also found to relieve craving for alcohol and is one of few FDA-approved medications for treatment of alcohol use disorder (AUD). While it was early on established that NTX acts by blocking the binding of endogenous opioid peptide ligands released by alcohol, experimental evidence emerged that could not be fully accounted for by this explanation alone, suggesting that NTX may have additional modes of action.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!