Abnormal morphology and subcortical projections to the medial geniculate in an animal model of autism.

Abnormal morphology and subcortical projections to the medial geniculate in an animal model of autism. Exp Brain Res. 2020 Nov 16;: Authors: Mansour Y, Ahmed SN, Kulesza R Abstract Auditory dysfunction, including hypersensitivity and tinnitus, is a common symptom of autism spectrum disorder (ASD). Prenatal exposure to the antiseizure medication valproic acid (VPA) significantly increases the risk of ASD in humans and similar exposure is utilized as an animal model of ASD in rodents. Animals exposed to VPA in utero have abnormal activity in their auditory cortex in response to sounds, fewer neurons, abnormal neuronal morphology, reduced expression of calcium-binding proteins, and reduced ascending projections to the central nucleus of the inferior colliculus. Unfortunately, these previous studies of central auditory circuits neglect the medial geniculate (MG), which serves as an important auditory relay from the midbrain to the auditory cortex. Here, we examine the structure and connectivity of the medial geniculate (MG) in rats prenatally exposed to VPA. Our results indicate that VPA exposure results in significantly smaller and fewer neurons in the ventral and medial nuclei of the MG. Furthermore, injections of the retrograde tract tracer fluorogold (FG) in the MG result in significantly fewer FG+ neurons in the inferior colliculus, superior olivary complex, and ventral cochlear nucleus. Together, we interpret these findings to in...
Source: Experimental Brain Research - Category: Neuroscience Authors: Tags: Exp Brain Res Source Type: research