Chronic cannabinoid exposure produces lasting memory impairment and increased anxiety in adolescent but not adult rats

  • O'Shea M
  • Singh M
  • McGregor I
 et al. 
  • 112


    Mendeley users who have this article in their library.
  • 171


    Citations of this article.


Although many studies have examined the acute behavioural effects of cannabinoids in rodents, few have examined the lasting effects of cannabinoids at different developmental ages. This study compared lasting effects of cannabinoid exposure occurring in adolescence to that occurring in early adulthood. Forty, 30-day old (adolescent) and 18, 56-day old (adult) female albino Wistar rats were injected with vehicle or incremental doses of the cannabinoid receptor agonist (-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hydroxypropyl) cyclohexanol (CP 55,940) once per day for 21 consecutive days (150, 200 and 300 microg/kg i.p. for 3, 8 and 10 days, respectively). Following a 21-day drug-free period, working memory was assessed using an object recognition task. Locomotor activity was also measured in the object recognition apparatus via a ceiling-mounted passive infrared sensor. Three days later, anxiety was assessed using a social interaction test. In the object recognition task, significantly poorer working memory was observed in the adolescent but not adult CP 55,940-treated rats. Adolescent, but not adult CP 55,940-treated rats, also exhibited a significant decrease in social interaction with a novel conspecific. These results suggest that chronic exposure to a cannabinoid receptor agonist well after the immediate postnatal period, but before reaching sexual maturity, can lead to increased anxiety and a lasting impairment of working memory.

Author-supplied keywords

  • Adolescent
  • Anxiety
  • CP 55,940
  • Cannabinoid
  • Memory
  • Object recognition
  • Rat
  • Social interaction

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Melanie O'Shea

  • Malini E. Singh

  • Iain S. McGregor

  • Paul E. Mallet

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free