Lasting effects of repeated ∆9 -tetrahydrocannabinol vapour inhalation during adolescence in male and female rats.
Jacques D. Nguyen, Kevin M Creehan, Tony M Kerr, Michael A. Taffe
British Journal of Pharmacology 2020 DOI: 10.1111/bph.14856 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental animal study Peer reviewed |
|---|---|
| Population | Male and female adolescent rats |
| Duration | Twice daily 30-minute sessions from PND 35-39 and PND 42-46; thermoregulatory assessment from PND 86-94 |
| Topics | Cannabis |
| Key findings | Repeated THC vapor inhalation during adolescence produces lasting tolerance to THC hypothermia and increases fentanyl self-administration in female rats, while increasing food intake in males. |
Abstract
Adolescents are regularly exposed to ∆9 -tetrahydrocannabinol (THC) via smoking and, more recently, vaping cannabis extracts. Growing legalization of cannabis for medical and recreational purposes, combined with decreasing perceptions of harm, makes it increasingly important to determine the consequences of frequent adolescent exposure for motivated behaviour and lasting tolerance in response to THC. Male and female rats inhaled THC vapour, or that from the propylene glycol (PG) vehicle, twice daily for 30 min from postnatal day (PND) 35-39 and PND 42-46 using an e-cigarette system. Thermoregulatory responses to vapour inhalation were assessed by radio-telemetry during adolescence and from PND 86-94. Chow intake was assessed in adulthood. Blood samples were obtained from additional adolescent groups following initial THC inhalation and after 4 days of twice daily exposure. Additional groups exposed repeatedly to THC or PG during adolescence were evaluated for intravenous self-administration of oxycodone as adults. Female, not male, adolescents developed tolerance to the hypothermic effects of THC inhalation in the first week of repeated exposure despite similar plasma THC levels. Each sex exhibited tolerance to THC hypothermia in adulthood after repeated adolescent THC. However, enhanced potency was found in females. Repeated THC male rats consumed more food than their PG-treated control group, without significant bodyweight differences. Adolescent THC did not alter oxycodone self-administration in either sex but increased fentanyl self-administration in females. Repeated THC vapour inhalation in adolescent rats has lasting consequences observable in adulthood.
Comparable studies
Other preclinical and animal studies on cannabis, most cited first.
Citations in the library
Cited by 10
- Influence of Carrier Oil, Sex, and Age on Pharmacokinetic and Acute Behavioral Effects of Vaporized Cannabis Extract in Mice. Cannabis and Cannabinoid Research December 1, 2025
- Chronic Δ9-tetrahydrocannabinol exposure during adolescence is associated with persistent behavioural tolerance in adult nonhuman primates. British Journal of Pharmacology November 1, 2025
- Adolescent cannabinoid vapour exposure sex-dependently alters the relationship between vulnerability traits and ethanol self-administration and modifies naltrexone actions on ethanol intake in rats. Neuropharmacology May 1, 2026
- Sex Differences in Response-Contingent Cannabis Vapor Administration During Adolescence Mediate Enduring Effects on Behavioral Flexibility and Prefrontal Microglia Activation in Rats Cannabis and Cannabinoid Research January 8, 2024
- Long-term effects of THC exposure on reward learning and motivated behavior in adolescent and adult male rats. Psychopharmacology May 2023
and 5 more in the library
Cites 13
- Intravenous self-administration of mephedrone, methylone and MDMA in female rats Neuropharmacology January 17, 2015
- Δ9-tetrahydrocannabinol attenuates oxycodone self-administration under extended access conditions. Neuropharmacology June 1, 2019
- Effects of Δ9-THC and cannabidiol vapor inhalation in male and female rats. Psychopharmacology September 2018
- Tolerance to hypothermic and antinoceptive effects of ∆9-tetrahydrocannabinol (THC) vapor inhalation in rats. Pharmacology, Biochemistry, and Behavior September 2018
- Escalation of intravenous self-administration of methylone and mephedrone under extended access conditions. Addiction Biology September 2017
and 8 more in the library