CONICET | Buscador de Institutos y Recursos Humanos

Cannabis is the most commonly used illegal drug worldwide, especially among people of reproductive age. Its biological effects are mediated by the endocannabinoid system (eCS), which is a complex lipid signaling system composed of the endogenous ligand, their receptors (CB1 and CB2), and their biosynthesizing and catabolizing enzymes. The main psychoactive component of Cannabis sativa is Δ9-tetrahydrocannabinol (THC), a highly lipid soluble molecule that can cross the placenta and the blood-brain barrier with ease, accumulating in fetal tissues, particularly the brain.Several studies have shown that the eCS plays an important role in reproduction, from egg fertilization to parturition. Therefore, the aim of this study was to investigate whether prenatal cannabis exposure is associated with adverse effects throughout pregnancy and offspring behavioral and cognitive development. We administered THC oil (0,3 𝝻g/𝝻l) intragastrically since day 1 (vaginal plug observation) until the day before the onset of labor. We analyzed different gestation parameters and observed that THC mice presented lower reproductive efficiency (36.9%) than vehicle (57.2%) and control mice (71.4%). We also observed that pregnant mice treated with THC presented lower body weight on day 16 of gestation vs vehicle and control. This trend persisted during lactation. However, no differences were found on offspring physical development parameters (body weight, pinnae detachment, incisor eruption and eye opening). Additionally, we observed increased mortality of the pups in the first week of life exclusively within the THC group.We performed behavioral tests when the offspring reached adulthood and found differences in the THC-exposed group when compared to vehicle and control mice. In conclusion, our results suggest that chronic use of cannabis oil with high THC content during pregnancy could potentially lead to adverse pregnancy outcomes.