Year: 2014
Type: dissertation
Abstract: Traumatic events often have adverse effects on an individual’s behavior. However, the outcomes of such an experience vary, some individuals being more resilient than others. It has been determined that the presence of control can block the development of learned helplessness in rats when they are subjected to escapable shock (ES) rather than inescapable shock (IS). When the presence of control is recognized, the ventral medial prefrontal cortex (vmPFC) pyramidal neurons inhibits the dorsal raphe nucleus (DRN) preventing prolonged excitation and subsequent sensitization of the DRN. The objective here was to ascertain if NMDA receptors in the posterior dorsal medial striatum (pDMS) is involved in modulating the DRN response during stress by local microinjection of the NMDA receptor antagonist AP5. Both the acute and long term impact of stress was observed and compared to the behavior of rats who received no such treatment (home cage controls, HC). Rats that received AP5 injections into the pDMS showed similar results to rats subjected to IS despite undergoing ES. They displayed higher serotonin (5-HT) concentrations in the DRN during stress and lower social exploration times 24 hours afterwards. When intra-pDMS AP5 injected rats were given IS a week after ES, they showed a deficit in shuttlebox escape learning in addition to the reduced social exploration times. The results imply that, in addition to the vmPFC, the pDMS is also involved in behavioral immunization.
Author: Janet Kim
Institution: University of Colorado Boulder
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2388058562