Prenatal Cannabis Vapor Exposure Altered Brain Synapses and Memory in Rat Offspring
Rat offspring exposed to vaporized high-potency cannabis during gestation showed remodeled hippocampal synapses, downregulated CB1 receptors, increased neural excitability, and lasting spatial memory deficits in both sexes.
Quick Facts
What This Study Found
Prenatal exposure to vaporized cannabis (14.7% THC) from gestational day 8 to 21 caused: increased synaptic vesicle recycling pools and vGlut1 abundance (presynaptic remodeling), downregulation of CB1 receptors at both excitatory and inhibitory synapses, increased axonal recruitment and synaptic efficacy at hippocampal CA1 synapses, and spatial memory deficits in both male and female adolescent offspring.
Key Numbers
14.7% THC cannabis strain; exposure gestational day 8-21; increased vGlut1 and synaptic vesicle recycling pool; CB1R downregulated at glutamatergic and GABAergic synapses; increased axonal recruitment and synaptic efficacy at CA1; spatial memory deficits in both sexes during adolescence
How They Did This
Pregnant rats were exposed to vapor from a commercially available high-potency cannabis strain (THC 14.7%) from gestational day 8 to 21. Offspring were assessed using primary hippocampal cell cultures, electrophysiology on brain slices, and behavioral memory tests.
Why This Research Matters
Most prenatal cannabis research uses injected THC, but most humans smoke or vaporize. This study used a clinically relevant exposure method (vaporized whole cannabis) and a market-representative potency (14.7% THC), making the results more translatable to real-world prenatal exposure.
The Bigger Picture
The finding that prenatal cannabis vapor causes presynaptic remodeling and CB1 receptor changes alongside lasting memory deficits provides a biological mechanism connecting prenatal exposure to cognitive outcomes, using an exposure method that matches human consumption patterns.
What This Study Doesn't Tell Us
Rat model may not fully translate to humans, single cannabis strain tested, vaporization parameters may differ from human use, limited to hippocampal assessments, no dose-response comparison, offspring assessed only through adolescence
Questions This Raises
- ?Would lower-potency cannabis produce similar effects?
- ?Do the synaptic changes persist into adulthood?
- ?Could the CB1 receptor downregulation be a compensatory mechanism that protects against some effects while impairing others?
Trust & Context
- Key Stat:
- Prenatal cannabis vapor exposure caused lasting spatial memory deficits in both male and female offspring
- Evidence Grade:
- Single animal study but with clinically relevant exposure method (vaporized whole cannabis at market potency); comprehensive multi-level assessment
- Study Age:
- Published 2025
- Original Title:
- Prenatal Exposure to Vaporized High-Potency Cannabis Affects Hippocampal Synaptic Remodeling and Efficacy, Axonal Excitability, and Memory in Offspring.
- Published In:
- Journal of neurochemistry, 169(7), e70153 (2025)
- Authors:
- Cairus, Andrea, Brizolara, Facundo, Kunizawa, Héctor, Clouzet, Vanina, Gonzalez, Giuliana, Alsina-Llanes, Marcela, Dellepiane, Lucía, Fernández, Santiago, García-Carnelli, Carlos, Umpierrez, Eleuterio, Borde, Michel, Prieto, José Pedro, Vitureira, Nathalia
- Database ID:
- RTHC-06144
Evidence Hierarchy
Tests effects in animals (usually mice or rats), not humans.
What do these levels mean? →Frequently Asked Questions
Does vaping cannabis during pregnancy affect the baby's brain?
In rats, prenatal exposure to vaporized high-potency cannabis altered hippocampal synapse structure, reduced key receptors, and caused lasting spatial memory deficits in offspring of both sexes during adolescence.
Why does this study matter more than others on prenatal cannabis?
Most prior studies injected pure THC. This study used vaporized whole cannabis at a market-representative potency (14.7% THC), making the exposure method and dose more relevant to how humans actually consume cannabis.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-06144APA
Cairus, Andrea; Brizolara, Facundo; Kunizawa, Héctor; Clouzet, Vanina; Gonzalez, Giuliana; Alsina-Llanes, Marcela; Dellepiane, Lucía; Fernández, Santiago; García-Carnelli, Carlos; Umpierrez, Eleuterio; Borde, Michel; Prieto, José Pedro; Vitureira, Nathalia. (2025). Prenatal Exposure to Vaporized High-Potency Cannabis Affects Hippocampal Synaptic Remodeling and Efficacy, Axonal Excitability, and Memory in Offspring.. Journal of neurochemistry, 169(7), e70153. https://doi.org/10.1111/jnc.70153
MLA
Cairus, Andrea, et al. "Prenatal Exposure to Vaporized High-Potency Cannabis Affects Hippocampal Synaptic Remodeling and Efficacy, Axonal Excitability, and Memory in Offspring.." Journal of neurochemistry, 2025. https://doi.org/10.1111/jnc.70153
RethinkTHC
RethinkTHC Research Database. "Prenatal Exposure to Vaporized High-Potency Cannabis Affects..." RTHC-06144. Retrieved from https://rethinkthc.com/research/cairus-2025-prenatal-exposure-to-vaporized
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.