This study used pregnant C57BL/6J mice to compare the effects of prenatal exposure to ethanol vapor (designated ALC), the cannabinoid receptor agonist CP-55,940 (0.75 mg/kg; designated CB), the combination of both agents (ALC+CB), and a drug-free control (CON). Exposures were administered on gestational days 12–15. The experimental design contrasts single-drug exposures with co-exposure to evaluate persistent effects on adult ethanol-related behaviors and cannabinoid-system proteomics.
Adult offspring were tested beginning on postnatal day 200. Behavioral assessments included two complementary paradigms. First, home-cage ethanol drinking was measured in a cohort reported as N=108. Second, operant self-administration experiments were performed in a separate cohort (N=96) and included fixed-ratio schedules, progressive-ratio schedules (including a 40% ethanol condition), extinction training, and reinstatement testing. These assays were used to quantify both consumption and motivated ethanol-seeking across groups and sexes.
Protein abundance of cannabinoid receptor 1 (CNR1) and the cannabinoid receptor interacting protein CNRIP1 was quantified in the medial prefrontal cortex (mPFC) and the dorsomedial striatum in a subset of subjects (N=57). These molecular measures were then compared with within-subject drinking and operant behavior to test for associations between cannabinoid-system protein levels and ethanol-seeking phenotypes.
Prenatal exposure to the cannabinoid agonist (CB) increased cumulative home-cage ethanol intake relative to controls, with the effect driven primarily by males. The abstract reports a sex-dependent pattern in which males showed pronounced increases in voluntary ethanol consumption after prenatal CB exposure. Female outcomes in home-cage intake were described as less prominent in the CB-only condition in the abstract.
Under progressive-ratio testing with a 40% ethanol solution, males prenatally exposed to both alcohol and cannabinoid (ALC+CB) consumed more than all other male groups, indicating enhanced motivation for ethanol under high-effort conditions. Among females, all exposed groups (ALC, CB, and ALC+CB) consumed more than female controls under the 40% progressive-ratio condition.
ALC+CB males also exhibited greater extinction responding compared with all other male groups, suggesting more persistent seeking when reinforcement was removed. During reinstatement testing, ALC+CB males showed greater reinstatement intake relative to their baseline than CON and ALC males. Together, these operant outcomes describe a persistent enhancement in ethanol-seeking and motivation that is most pronounced in males subjected to prenatal co-exposure.
Protein analysis revealed sex-dependent effects of prenatal exposure on mPFC CNR1. In males, prenatal co-exposure (ALC+CB) increased mPFC CNR1 relative to all other groups. In contrast, female offspring from CB and ALC+CB groups showed reduced mPFC CNR1 compared with other conditions reported in the abstract.
Importantly, higher mPFC CNR1 abundance was associated with several behavioral measures—fixed-ratio intake, 40% progressive-ratio intake, extinction responding, and reinstatement—but these relationships were observed exclusively in males. These convergent behavioral and molecular findings link elevated mPFC CNR1 to a male-specific ethanol-seeking phenotype after prenatal co-exposure.
The authors conclude that prenatal co-exposure to alcohol and a cannabinoid produced a persistent, male-specific phenotype characterized by enhanced ethanol seeking in late adulthood and accompanied by elevated mPFC CNR1. This behavioral–molecular convergence suggests that corticostriatal cannabinoid signaling may be a mechanistic substrate for increased ethanol motivation following prenatal co-exposure. The authors propose that future investigations should manipulate cannabinoid signaling in corticostriatal circuits to determine whether such interventions can attenuate exposure-induced ethanol consumption in late adulthood.
This summary is based on the abstract of a preprint and the authors note that the article has not been peer reviewed. Specific experimental details not reported in the provided source text include, but may not be limited to, the number of litters versus individual offspring per group, exact timing and method parameters for ethanol vapor exposure and CP-55,940 administration beyond gestational days 12–15, detailed statistical values (e.g., effect sizes, p-values), full behavioral protocols, and whether CNRIP1 showed any group- or sex-specific differences beyond CNR1. Those methodological and statistical details are not reported in the abstract and would need to be obtained from the full manuscript or supplementary material for full evaluation.