Mice with reduced Reelin protein showed worse behavioral outcomes after adolescent THC exposure
Mice with reduced levels of the brain development protein Reelin showed more severe social, behavioral, and stress-related impairments after chronic adolescent THC exposure compared to normal mice.
Quick Facts
What This Study Found
Heterozygous Reeler mice (reduced Reelin) treated with THC during adolescence showed impaired social behaviors, elevated disinhibitory phenotypes, and increased stress reactivity compared to wild-type mice given the same THC treatment. These effects were sex-specific. Wild-type mice showed less severe behavioral changes from the same THC exposure.
Key Numbers
THC dose: 10 mg/kg chronic during adolescence. Two-week washout before testing. HR mice showed impaired social behavior, elevated disinhibition, and increased stress reactivity compared to WT mice with same THC exposure. Effects were sex-specific.
How They Did This
Heterozygous Reeler (HR) mice and wild-type littermates received chronic high-dose THC (10 mg/kg) during adolescence. Two weeks after the last injection, mice underwent multiple behavioral tests: working memory, social interaction, locomotor activity, anxiety-like responses, stress reactivity, and pre-pulse inhibition.
Why This Research Matters
Reelin is implicated in brain development and psychiatric disorders including schizophrenia. This study suggests that genetic variations affecting Reelin levels could make some individuals more vulnerable to lasting behavioral effects from adolescent cannabis use.
The Bigger Picture
Not everyone who uses cannabis as a teenager develops problems. Gene-environment interaction studies like this one help explain individual vulnerability. If Reelin-related genetic variants predict cannabis sensitivity in humans, it could eventually enable personalized risk assessment.
What This Study Doesn't Tell Us
High THC dose (10 mg/kg) may not reflect typical human use. Mouse behavior may not translate to human psychiatric outcomes. Only chronic high-dose regimen tested. Two-week follow-up may miss longer-term effects.
Questions This Raises
- ?Do human Reelin gene variants predict vulnerability to cannabis-related psychiatric outcomes?
- ?Would lower THC doses produce similar gene-environment interactions?
- ?Are the behavioral effects reversible with longer abstinence?
Trust & Context
- Key Stat:
- Reelin-deficient mice showed worse behavioral outcomes from same THC exposure
- Evidence Grade:
- Well-controlled animal study with genetic model. Preliminary because mouse behavioral tests have limited human translation.
- Study Age:
- 2021 preclinical study.
- Original Title:
- Reelin deficiency contributes to long-term behavioral abnormalities induced by chronic adolescent exposure to Δ9-tetrahydrocannabinol in mice.
- Published In:
- Neuropharmacology, 187, 108495 (2021)
- Authors:
- Iemolo, Attilio(3), Montilla-Perez, Patricia(3), Nguyen, Jacques, Risbrough, Victoria B, Taffe, Michael A, Telese, Francesca
- Database ID:
- RTHC-03216
Evidence Hierarchy
Tests effects in animals (usually mice or rats), not humans.
What do these levels mean? →Frequently Asked Questions
What is Reelin and why does it matter?
Reelin is a protein critical for brain development and maintaining synaptic connections. It has been implicated in schizophrenia, and mice with reduced Reelin levels show brain developmental differences relevant to psychiatric conditions.
Were male and female mice affected the same way?
No. The behavioral effects of THC in Reelin-deficient mice were sex-specific, though the study does not detail which sex was more affected for each outcome.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-03216APA
Iemolo, Attilio; Montilla-Perez, Patricia; Nguyen, Jacques; Risbrough, Victoria B; Taffe, Michael A; Telese, Francesca. (2021). Reelin deficiency contributes to long-term behavioral abnormalities induced by chronic adolescent exposure to Δ9-tetrahydrocannabinol in mice.. Neuropharmacology, 187, 108495. https://doi.org/10.1016/j.neuropharm.2021.108495
MLA
Iemolo, Attilio, et al. "Reelin deficiency contributes to long-term behavioral abnormalities induced by chronic adolescent exposure to Δ9-tetrahydrocannabinol in mice.." Neuropharmacology, 2021. https://doi.org/10.1016/j.neuropharm.2021.108495
RethinkTHC
RethinkTHC Research Database. "Reelin deficiency contributes to long-term behavioral abnorm..." RTHC-03216. Retrieved from https://rethinkthc.com/research/iemolo-2021-reelin-deficiency-contributes-to
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.