Cited by 133Neuropeptides and Animal PhysiologyNeurotransmitter Receptor Influence on BehaviorSubstance Abuse Treatment and Outcomes

κ-opioid receptors are implicated in the increased potency of intra-accumbens nalmefene in ethanol-dependent rats

Open access
Nealey, Kathryn A., Smith, Alexander W., Davis, Seth M., Smith, Daniel G., Walker, Brendan M.·2011·Neuropharmacology

Abstract

Previously, it was shown that ethanol-dependent animals display increased sensitivity to the general opioid receptor antagonist nalmefene compared to naltrexone. It was hypothesized that the dissociable effects of the two antagonists were attributable to a κ-opioid receptor mechanism. Nucleus accumbens dynorphin is upregulated following chronic ethanol exposure and such neuroadaptations could contribute to nalmefene's increased potency in ethanol-dependent animals. To test this hypothesis, male Wistar rats were trained to self-administer ethanol using an operant conditioning procedure. Animals were then implanted with bilateral intra-accumbens shell guide cannulae and assigned to either a chronic intermittent ethanol vapor-exposure condition (to induce dependence) or an air-exposed control group. Following a one-month exposure period, nalmefene, nor-binaltorphimine (nor-BNI; selective for κ-opioid receptors) or a combination of the selective opioid receptor antagonists CTOP and naltrindole (selective for the μ- and δ-opioid receptors, respectively) were site-specifically infused into the nucleus accumbens shell prior to ethanol self-administration sessions during acute withdrawal. Nalmefene and CTOP/naltrindole dose-dependently reduced ethanol self-administration in nondependent and dependent animals, whereas nor-BNI selectively attenuated ethanol self-administration in ethanol-dependent animals without affecting the self-administration of nondependent animals. Further analysis indentified that intra-accumbens shell nalmefene was more potent in ethanol-dependent animals and that the increased potency was attributable to a κ-opioid receptor mechanism. These data support the concept that dysregulation of DYN/κ-opioid receptor systems contributes to the excessive self-administration observed in dependent animals and suggest that pharmacotherapeutics for ethanol dependence that target κ-opioid receptors, in addition to μ- and δ-opioid receptors, are preferable to those that target μ- and δ-opioid receptor mechanisms alone.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1016/j.neuropharm.2011.02.012

Cites

67 of 67 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The effects of k-opioid receptor blockade on high compulsive-like alcohol intake may be mediated by the extended amygdala, including the CeA and shell of the NAc.

    “These effects may be mediated by the extended amygdala, including the CeA and shell of the NAc (Nealey et al., 2011).”

    From Drug Addiction: Hyperkatifeia/Negative Reinforcement as a Framework for Medications Development (2021) · cites this paper as Nealey et al., 2011

    The Discussion reports that blocking κ-opioid receptors in the nucleus accumbens shell attenuated excessive ethanol self-administration in dependent rats. It does not identify the central amygdala (CeA) or establish the extended amygdala as the mediating circuit; it also describes excessive intake rather than specifically compulsive-like intake. (LLM, conf=0.86)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Walker BM Zorrilla EP Koob GF Systemic kappa-opioid receptor antagonism by nor-binaltorphimine reduces dependence-induced excessive alcohol self-administration in rats Addict Biol 2011 16 116 119 20579007 PMC2988980

Cited by

Sorted by citations

Authors
Nealey, K. A., Smith, A. W., Davis, S. M., Smith, D. G., & Walker, B. M.
Affiliations
  • Washington State University (US)
  • Lundbeck (United States) (US)
Corresponding author
Walker, Brendan M.
Venue
Neuropharmacology
Publisher
Elsevier BV
Published
2011-07
Volume
61
Issue
1-2
Pages
35-42
ISSN
0028-3908 (ISSN-L)
OpenAlex
W2054879676
Cited by
133
References
66
Citations by year
2026: 3 · 2025: 6 · 2024: 4 · 2023: 7 · 2022: 7 · 2021: 7 · 2020: 2 · 2019: 5 · 2018: 13 · 2017: 11 · 2016: 15 · 2015: 11 · 2014: 9 · 2013: 15 · 2012: 14
FWCI
5.39
Type
journal article
Language
en
Open access
Locations
  • Neuropharmacology (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
National Institute on Alcohol Abuse and Alcoholism (R01AA020394)
Topics
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuropeptides and Animal Physiology
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurotransmitter Receptor Influence on Behavior
  • Health Sciences › Medicine › Epidemiology › Substance Abuse Treatment and Outcomes
Keywords
kappa opioid receptor, nalmefene, ethanol dependence, nucleus accumbens shell, dynorphin, nor-binaltorphimine, CTOP, naltrindole, ethanol self-administration, ethanol withdrawal, opioid antagonists
MeSH terms
Ethanol, Alcoholism, Animals, Male, Naltrexone, Nucleus Accumbens, Self Administration, Rats, Wistar, Receptors, Opioid, kappa, Rats, Infusions, Intraventricular

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review