The Effect of Prenatal THC Exposure on ASD-Relevant Sensorimotor Behaviour in Rats
Abstract
Prenatal cannabis exposure (PCE) has been implicated in the increased incidence of several neuropsychiatric disorders, including autism spectrum disorder (ASD). Due to the ongoing rise in cannabis usage, the present thesis investigated the effect of tetrahydrocannabinol (THC), the psychoactive constituent of cannabis, on a rat model of ASD. Male and Female Sprague-Dawley offspring were prenatally exposed to saline or THC from gestational day (GD)6 until GD21. Sensorimotor processing and gating, an aspect commonly disrupted in ASD, was assessed via the acoustic startle reflex (ASR), prepulse inhibition (PPI), and gap-prepulse inhibition (Gap-PPI). THC-exposed offspring exhibited a higher threshold, and a higher half-maximal response (ES50) for the ASR. Moreover, THC-exposed offspring showed higher PPI but no change in Gap-PPI. These findings indicated a lowered startle reactivity and heightened PPI. This thesis presents contrasting PPI data to previous neuropsychiatric models, building the foundation to better understand the sensitivity of model validity and the impact of prenatal THC exposure on a non-human model.