Grant: Project Grant

Cannabis is one of the most frequently used recreational drugs during pregnancy. In Canada, approximately 16.9% of women of childbearing age reported past-year use of cannabis in 2015 an increase from 12.6% in 2013. In utero cannabis or THC exposure negatively impacts birth weight and the neural circuitry involved in executive functioning, including response inhibition, attention, and visuospatial working memory. These effects are linked to altered brain morphology, specifically in the frontal cortex and parts of the limbic system. It is, however, important to note that the data collected so far on women consuming cannabis or one of its major psychoactive components (delta9-THC) during pregnancy suffer from confounding factors such as polysubstance use (e.g. tobacco, alcohol) that makes it hard to separate the unique effect of cannabis or THC. We propose here to account for these confounding variables and study in the monkey, a species close to humans, the deleterious effects of fetal THC exposure. We will investigate 1) the socio-affective outcomes on the fetal THC exposed monkey, at various stages of development, 2) the brain anatomical reorganization through a) ex vivo neuroimaging, b) classical neuroanatomy and c) immunohistochemistry. Our laboratory has 40-year expertise in monkey research and 25-year expertise in cannabinoid research. We should keep in mind that the developing brain is highly sensitive to intrusions and its harmonious development requests a fully sane fetal environment. It is rather unfortunate that society shall reap the burden of permanent deficits in cognition and social behavior. However, in order to develop more efficient therapies, more research on the basic neurobiological processes underlying behavioral dysfunction due to maternal THC consumption is needed.