Measurement of GluR1, NR1, GABRA2, GABRB2, and NR1 Expression in the Midbrain and Cerebral Cortex in the Acute Phase Post Moderate Traumatic Brain Injury
Traumatic brain injury (TBI) is a common phenomenon in the United States with over 1 million cases a year. TBI has been shown to harm dopaminergic signaling in the brain, impacting areas such as the ventral tegmental area and nucleus accumbens. To understand the impact of moderate TBI on the ventral tegmental area, we look at the expression of GABA and glutamate, which are excitatory and inhibitory neurotransmitters, by measuring the activity of GABA and glutamate receptors. In this preliminary study, we look at the activity of GABRA4, GABRB2, GluR1, and NR1 receptors through RT-PCR analysis. Adolescent mice were grouped into Sham or TBI groups and moderate TBI was inflicted on the TBI group using a controlled cortical impact model. Sham groups underwent surgery with no further modifications. After three days, brain samples from the midbrain and cerebral cortex were harvested and RT-PCR analysis was performed measuring expression of GABRA4, GABRB2, GluR1, and NR1 receptors in ipsilateral and contralateral areas. PCR data were compared to the stably expressed RPL 27 gene. Previous studies suggested increased expression of GABRA4, GABRB2, and GluR1 and decreased expression of NR1. Unexpectedly, GABRA4, GABRB2, and GluR1, along with NR1, had decreased expression post TBI. We hope to expand on this research through a western blot analysis of more precise regions of the brain such as the nucleus accumbens and ventral tegmental area.