Original ArticleMu (μ) Opioid Receptor Regulation of Ethanol-Induced Dopamine Response in the Ventral Striatum: Evidence of Genotype Specific Sexual Dimorphic Epistasis
Section snippets
Subjects
Mice (male and female, 4–16 months old, 21–38 g) were obtained from the National Institute on Drug Abuse (NIDA, Baltimore, Maryland) or bred at the University of Texas at Austin. The mice were housed in a humidity and temperature controlled room with a 12:12-hour light/dark cycle (lights on 7 am), and animals had free access to food and water. All animal experiments were conducted under protocols approved by the Institutional Animal Care and Use Committee at the University of Texas, following
Histological Analysis and Ca2+-Dependence of Dopamine Release
The microdialysis probe placements are shown in Figure 1. They were distributed either in the medial NAcc and passed through both the shell and core regions, or exclusively in the shell. The calcium-dependency, a functional measure of the physiological state of the dopamine nerve terminals during microdialysis sampling, was determined for all the animals used in the study. The criterion for acceptable calcium-dependency was the attainment of at least a 40% decrease in dialysate dopamine
Discussion
Our study is the first to report diminished ethanol-stimulated dopamine release in any MOPr knockout model. A secondary finding from the present study is the novel interaction between sex and genotype in the MOPr-dependence of ethanol-stimulated mesolimbic dopamine release. Female, but not male, 129SvEv-C57BL/6J mice were found to require the MOPr for the expression of the neurochemical response to ethanol. Similar results were observed following pharmacological blockade of the mu1 receptor. In
References (65)
- et al.
Sex-related differences in the effects of morphine and stress on visceral pain
Neuropharmacology
(1989) - et al.
Dopamine D3 receptor knockout mice and the motivational effects of ethanol
Pharmacol Biochem Behav
(2003) - et al.
Gender differences in the reinforcing properties of morphine
Pharmacol Biochem Behav
(2000) - et al.
Evidence that naloxonazine produces prolonged antagonism of central delta opioid receptor activity in vivo
Brain Res
(1984) - et al.
The contribution of genetics to addiction therapy approaches
Pharmacol Ther
(2005) Characterization of the effects of acute ethanol administration on the release of beta-endorphin peptides by the rat hypothalamus
Eur J Pharmacol
(1990)- et al.
Alcohol drinking is reduced by a mu 1- but not by a delta-opioid receptor antagonist in alcohol-preferring rats
Eur J Pharmacol
(1996) Involvement of mu-opioid receptors in alcohol drinking by alcohol-preferring AA rats
Pharmacol Biochem Behav
(1993)- et al.
Effect of mu opioid receptor blockade on alcohol intake in rats bred for high alcohol drinking
Pharmacol Biochem Behav
(1998) - et al.
The effects of selective blockade of delta and mu opiate receptors on ethanol consumption by C57BL/6 mice in a restricted access paradigm
Brain Res
(1993)
Naloxonazine actions in vivo
Eur J Pharmacol
mu Opioid receptor knockout in mice: effects on ligand-induced analgesia and morphine lethality
Brain Res Mol Brain Res
The neural basis of drug craving: an incentive-sensitization theory of addiction
Brain Res Brain Res Rev
Sex specific behavioural alterations in Mas-deficient mice
Behav Brain Res
Fentanyl increases dopamine release in rat nucleus accumbens: involvement of mesolimbic mu- and delta-2-opioid receptors
Neuroscience
Sex differences in opioid antinociception
J Pharmacol Exp Ther
Rewarding effects of ethanol and cocaine in mu opioid receptor-deficient mice
Naunyn Schmiedebergs Arch Pharmacol
Voluntary consumption of ethanol in 15 inbred mouse strains
Psychopharmacology (Berl)
Involvement of mu- and delta-opioid receptors in the effects of systemic and locally perfused morphine on extracellular levels of dopamine, DOPAC and HVA in the nucleus accumbens of the halothane-anaesthetized rat
Naunyn Schmiedebergs Arch Pharmacol
Efficacy and safety of naltrexone and acamprosate in the treatment of alcohol dependence: a systematic review
Addiction
Why sex matters for neuroscience
Nat Rev Neurosci
Basal and morphine-evoked dopaminergic neurotransmission in the nucleus accumbens of MOR- and DOR-knockout mice
Eur J Neurosci
Gender-related differences in the antinociceptive properties of morphine
J Pharmacol Exp Ther
Ethanol-induced conditioned place preference and activation in 15 inbred mouse strains
Alcohol Clin Exp Res
Autoradiographic localization of delta opioid receptors within the mesocorticolimbic dopamine system using radioiodinated [2-D- penicillamine, 5-D-penicillamine]enkephalin (125I-DPDPE)
Synapse
Dopamine activity in the nucleus accumbens during consummatory phases of oral ethanol self-administration
Alcohol Clin Exp Res
Introduction to Quantitative Genetics
Efficacy and tolerability of long-acting injectable naltrexone for alcohol dependence: a randomized controlled trial
JAMA
Influence of the endogenous opioid system on high alcohol consumption and genetic predisposition to alcoholism
J Psychiatry Neurosci
Suppression of ethanol-reinforced behavior by naltrexone is associated with attenuation of the ethanol-induced increase in dialysate dopamine levels in the nucleus accumbens
J Neurosci
Endomorphin-1 and −2 immunoreactive cells in the hypothalamus are labeled by fluoro-gold injections to the ventral tegmental area
J Comp Neurol
Ethanol consumption and reward are decreased in mu-opiate receptor knockout mice
Psychopharmacology (Berl)
Cited by (0)
- 1
AT is currently affiliated with Lexicon Genetics Inc., The Woodlands, Texas
- 2
IS is currently affiliated with the Department of Psychobiology (IS), Tohoku University Graduate School of Medicine, Sendai, Japan.