Male and female rats show different behavioral patterns during cannabinoid withdrawal | Research

The takeaway

Male and female rats exhibited qualitatively different withdrawal behaviors from the synthetic cannabinoid WIN 55,212-2, with females showing precipitated withdrawal at lower antagonist doses and sex-specific anxiety-like behaviors emerging weeks later.

People interested in cannabis dependence, withdrawal symptoms, and sex-based differences in drug responses.

Females showed withdrawal at 3 mg/kg rimonabant vs. 10 mg/kg for males

What the researchers found

Females showed precipitated withdrawal at 3 mg/kg rimonabant while males required 10 mg/kg. The individual somatic behaviors contributing to withdrawal scores differed by sex. At two weeks abstinence, females showed more grooming and marble manipulation than males, suggesting sex-specific anxiety-like responses.

Why it matters

Most cannabinoid withdrawal research has focused on males. This study demonstrates that withdrawal is not just more or less severe between sexes but qualitatively different, which has implications for how withdrawal is assessed and treated in clinical settings.

The numbers in context

Females: precipitated withdrawal at 3 mg/kg rimonabant. Males: precipitated withdrawal at 10 mg/kg. Spontaneous withdrawal quantifiable up to 24 hours post-final infusion. Estrous cycle was not affected by WIN infusions and did not correlate with withdrawal scores.

How the study worked

Adult male and female Long-Evans rats received escalating doses of WIN 55,212-2 via intrajugular infusion. Precipitated withdrawal was induced with rimonabant. Somatic behaviors were scored, locomotor activity tracked, and anxiety-like behavior assessed with elevated plus maze, open field, and marble burying tests at one and two weeks abstinence.

What this study cannot tell us

Used a synthetic cannabinoid (WIN 55,212-2), not THC, so results may not directly map to cannabis withdrawal. Rat behavior does not perfectly model human withdrawal experience. The anxiety-like tests at one and two weeks showed limited drug-treatment effects.

How to read the evidence

Well-designed animal study with multiple behavioral measures and both sexes represented. Limited by use of synthetic cannabinoid rather than THC and by inherent constraints of translating rat behavior to human experience.

When this study was published

Published in 2024 with controlled laboratory experiments.

The bigger picture

Clinical data show that women often report more severe cannabis withdrawal than men. This animal study supports those findings and adds that the types of withdrawal behaviors differ, not just the intensity, reinforcing the need for sex-specific approaches to treating cannabis dependence.

Questions still open

Would THC withdrawal produce the same sex-dependent patterns? What biological mechanisms make females more sensitive to cannabinoid withdrawal? Could sex-specific withdrawal profiles inform tailored treatment approaches?

Common questions

Do men and women experience cannabis withdrawal differently?

Clinical data suggest women often report more severe withdrawal. This animal study found that female rats also showed withdrawal at lower doses and exhibited different specific behaviors than males, supporting the idea of sex-based differences in withdrawal.

What is precipitated withdrawal?

Precipitated withdrawal occurs when an antagonist drug (in this case rimonabant) rapidly blocks cannabinoid receptors, triggering immediate withdrawal symptoms rather than waiting for the drug to naturally clear the body.

Read the original research

Somatic and anxiety-like behaviors in male and female rats during withdrawal from the non-selective cannabinoid agonist WIN 55,212-2.

Pharmacology, biochemistry, and behavior, 236, 173707

View on PubMed ↗Publisher’s paper ↗

Citation

Brewer, Abigail L; Felter, Claire E; Sternitzky, Anna R; Spencer, Sade M. (2024). Somatic and anxiety-like behaviors in male and female rats during withdrawal from the non-selective cannabinoid agonist WIN 55,212-2.. Pharmacology, biochemistry, and behavior, 236, 173707. https://doi.org/10.1016/j.pbb.2024.173707