7 - The impact of pubertal exposure to cannabis on the brain: a focus on animal studies

Summary

This chapter surveys possible lasting consequences of cannabinoid exposure during crucial periods of pubertal and adolescent maturation reported from animal studies. Endocannabinoids and their cannabinoid receptors, CB1 and CB2, are present from the early stages of gestation and play a number of vital roles for the developing organism. Beside direct alterations in the endocannabinoid or other neurotransmitter systems, adolescent/pubertal cannabinoid exposure has been reported to affect cortical and limbic systems in particular. Global evidence indicates that cannabis use/abuse acts as a risk factor for the emergence of schizophrenia, especially among early-onset cannabis users. Similar indications were observed in animal studies, where chronic pubertal, but not adult, cannabinoid treatment resulted in lasting behavioral deficits, resembling at least some aspects of schizophrenia. Data from animal research point out clearly that the age at which an individual is exposed to cannabinoids has major impact on subsequent effects of this drug.