Stress disrupts brain reward circuit plasticity in male rats but not females, and the endocannabinoid system is responsible

Acute stress eliminated a key form of synaptic plasticity in the insular cortex-to-nucleus accumbens pathway in male rats but not females, and this effect was reversed by blocking CB1 receptors.

Gauthier, Manon et al.·Progress in neuro-psychopharmacology & biological psychiatry·2025·Moderate EvidenceAnimal StudyAnimal Study
RTHC-06517Animal StudyModerate Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

Under basal conditions, males showed equal proportions of LTP and LTD in the insular cortex-to-NAc pathway, while females predominantly showed LTP. Stress eliminated LTD in males 24 hours after exposure, reversed by CB1 receptor blockade. Females showed no stress-induced plasticity changes.

Key Numbers

Males: 50/50 LTP/LTD at baseline, LTD eliminated 24h post-stress. Females: predominantly LTP at baseline, no change with stress. CB1 blockade reversed the male-specific effect.

How They Did This

Male and female rats underwent 2 hours of acute restraint stress. In vivo electrophysiological recordings of the anterior insular cortex-to-NAc core pathway were performed immediately and 24 hours post-stress. CB1 receptor blockade tested systemically and locally.

Why This Research Matters

The insular cortex processes interoceptive signals and sends them to the reward center. Stress-induced disruption of this pathway could explain why stress alters reward processing in males, while females may be protected through different baseline circuit properties.

The Bigger Picture

Sex differences in stress vulnerability are well documented clinically but poorly understood mechanistically. This study identifies a specific circuit and molecular mechanism that differs fundamentally between sexes.

What This Study Doesn't Tell Us

Acute restraint stress is one paradigm and may not generalize. Only one circuit was examined. Functional consequences were not directly tested.

Questions This Raises

  • ?Does the baseline sex difference in insular-NAc plasticity explain differential vulnerability to stress-related psychiatric disorders?
  • ?Would chronic stress produce similar or different plasticity changes?

Trust & Context

Key Stat:
Stress eliminated long-term depression in the insular-NAc pathway via the endocannabinoid system; females were unaffected
Evidence Grade:
Rigorous electrophysiology with both systemic and local pharmacological validation, though limited to one stress paradigm and one neural circuit.
Study Age:
2025 publication.
Original Title:
Sex-dependent effects of stress on aIC-NAc circuit neuroplasticity: Role of the endocannabinoid system.
Published In:
Progress in neuro-psychopharmacology & biological psychiatry, 138, 111335 (2025)
Database ID:
RTHC-06517

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

What is the insular cortex-nucleus accumbens pathway?

The insular cortex processes signals about internal body states and sends this information to the nucleus accumbens, a key reward and motivation center. This pathway helps translate internal states into motivated behavior.

Why are females protected from this stress effect?

Females showed predominantly LTP (not a balance of LTP and LTD) at baseline, meaning stress had no LTD to eliminate. This fundamentally different baseline circuit property may represent a sex-specific resilience mechanism.

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Cite This Study

RTHC-06517·https://rethinkthc.com/research/RTHC-06517

APA

Gauthier, Manon; Hebert, Léo-Paul; Dugast, Emilie; Lardeux, Virginie; Letort, Kevin; Thiriet, Nathalie; Belnoue, Laure; Balado, Eric; Solinas, Marcello; Belujon, Pauline. (2025). Sex-dependent effects of stress on aIC-NAc circuit neuroplasticity: Role of the endocannabinoid system.. Progress in neuro-psychopharmacology & biological psychiatry, 138, 111335. https://doi.org/10.1016/j.pnpbp.2025.111335

MLA

Gauthier, Manon, et al. "Sex-dependent effects of stress on aIC-NAc circuit neuroplasticity: Role of the endocannabinoid system.." Progress in neuro-psychopharmacology & biological psychiatry, 2025. https://doi.org/10.1016/j.pnpbp.2025.111335

RethinkTHC

RethinkTHC Research Database. "Sex-dependent effects of stress on aIC-NAc circuit neuroplas..." RTHC-06517. Retrieved from https://rethinkthc.com/research/gauthier-2025-sexdependent-effects-of-stress

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.