Male and female mice showed distinct patterns of neuropeptide gene changes in the central amygdala during acute and protracted alcohol abstinence, with NPY, somatostatin, and CRH responding differently by sex and withdrawal stage.
25 genes assessedNeuropeptide, receptor, and enzyme genes screened in the central amygdala during acute and protracted alcohol abstinence in male and female mice
What the researchers found
During acute abstinence (1 day), male mice had upregulated NPY, somatostatin (Sst), and NPY receptor Y2 (Npy2r) in the CeA, while females showed upregulated GABA receptor subunit alpha 2 (Gabra2) and the peptidase angiotensinase C (Prcp). Males also had downregulated NMDA receptor subunit Grin1.
During protracted abstinence (7 days), male mice maintained elevated Npy2r, NPY, and somatostatin expression. Female mice showed increased corticotropin-releasing hormone (CRH) and NPY expression. The gene expression profiles differed significantly between sexes at both time points, suggesting sex-specific neuropeptide responses to binge alcohol exposure and withdrawal.
Why it matters
Alcohol use disorder affects men and women differently, yet most neuroscience research has historically focused on males. This study reveals that the neuropeptide systems in the brain's emotional center respond to binge drinking and withdrawal in sex-specific ways. Understanding these differences is critical for developing targeted treatments — a drug that modulates NPY signaling, for example, might work differently in men versus women. The involvement of stress-related peptides like CRH specifically in female mice also suggests different vulnerability pathways.
How the study worked
Two separate cohorts of C57BL/6J mice underwent the 'drinking in the dark' (DID) binge drinking protocol. Central amygdala (CeA) brain tissue was collected at 1 day (acute) and 7 days (protracted) abstinence after DID. Quantitative reverse-transcription PCR (qRT-PCR) was used to measure relative gene expression changes of 25 genes related to G protein-coupled receptors, neuropeptides, ion channel subunits, and enzymes previously implicated in alcohol use disorder.
What this study cannot tell us
This is a mouse study, and neuropeptide expression patterns may differ in human brains. Only gene expression (mRNA) was measured, not protein levels or functional neuropeptide activity. The DID model represents binge drinking specifically and may not capture other patterns of alcohol consumption. Only two time points (1 and 7 days) were assessed, missing potential dynamic changes between and beyond these windows. The number of mice per group is not specified in the abstract.
How to read the evidence
This is a preclinical study in mice using a well-established binge drinking model. The comprehensive gene expression analysis across sex and time points provides valuable mechanistic insights, but the findings are in an animal model and measure mRNA only, not functional outcomes.
When this study was published
Published in 2024, this study is recent and reflects the current emphasis on studying sex differences in addiction neuroscience and neuropeptide biology.
The bigger picture
This study contributes to the growing understanding that neuropeptides are central players in addiction biology — not just supporting cast members. The sex-specific patterns observed here align with clinical observations that alcohol use disorder manifests differently in men and women. As neuropeptide-targeted therapies (NPY agonists, CRH antagonists) continue to be explored for addiction treatment, these sex differences will be critical for designing effective interventions and clinical trials.
Questions still open
- Do these sex-specific neuropeptide changes translate to differences in relapse vulnerability or withdrawal severity in humans?
- Would NPY-targeted therapies for alcohol use disorder need to be dosed or designed differently for men and women?
- Does the upregulation of CRH specifically in female mice during protracted abstinence contribute to higher stress-related relapse risk in women?
Common questions
Why do male and female brains respond differently to binge drinking?
What is neuropeptide Y and why is it important in addiction?
Read the original research
Dynamic regulation of CeA gene expression during acute and protracted abstinence from chronic binge drinking of male and female C57BL/6J mice.
Alcohol (Fayetteville, N.Y.), 120, 179-193
Citation
Méndez, Hernán G; Neira, Sofia; Flanigan, Meghan E; Haun, Harold L; Boyt, Kristen M; Thiele, Todd E; Kash, Thomas L. (2024). Dynamic regulation of CeA gene expression during acute and protracted abstinence from chronic binge drinking of male and female C57BL/6J mice.. Alcohol (Fayetteville, N.Y.), 120, 179-193. https://doi.org/10.1016/j.alcohol.2024.06.005