Dissertation/Thesis Abstract

Examination of Opioid and Glucocorticoid Receptor Pathways in Rhesus Macaques (Macaca mulatta) Exhibiting Self-Injurious Behaviors
by Foret, Brittany L., M.S., University of Louisiana at Lafayette, 2017, 87; 10270861
Abstract (Summary)

Self-injurious behaviors are a maladaptive set of behaviors exhibited by a diverse population, and are characterized by self-directed mutilation or harm, such as cutting, burning, head banging, and scab picking, among others. This thesis aims to explore two prevailing hypotheses proposing disruptions in the HPA axis and endogenous opioid system in individuals with SIB by using qRT-PCR. Many studies have been conducted with results supporting both hypotheses, but are limited to behavioral analysis and measurements of opioids and HPA axis ligands from urine, plasma, or CSF. None of these studies directly explore the specific brain regions of individuals exhibiting SIB. Here, we show altered expression of the glucocorticoid receptor, Nr3c1, in the amygdala of males with SIB and a downregulation of mineralocorticoid receptor, Nr3c2, in the amygdala of females with SIB. Furthermore, upregulations of Nr3c2 and downregulation of the Nr3c1 are seen in the hippocampus of females with SIB. Because of the roles of the amygdala in activating the HPA axis and the hippocampus in suppressing the HPA axis, the aforementioned gene expression disruptions likely translate to an inability to efficiently regulate the HPA axis. In the endogenous opioid system, expression of both prodynorphin, Pdyn, and opioid receptor mu 1, Oprm1, are disregulated in both males and females with SIB, but in a dynamic way. These alterations in opioid transcripts may imply impairments in the reward experience, leading to aberrant behaviors such as SIB to experience reward. Our results support both hypotheses, that disruptions in expression are present in genes involved in the HPA axis and endogenous opioid signaling, and also show a sex-biased difference in expression in both males and females with SIB. The results also elucidate a complexity to the neurobiology of SIB that requires further research.

Indexing (document details)
Advisor: Smith, Karen M.
Commitee: Kulkarni, Ritwij, Leberg, Paul
School: University of Louisiana at Lafayette
Department: Biology
School Location: United States -- Louisiana
Source: MAI 57/01M(E), Masters Abstracts International
Subjects: Biology, Neurosciences
Keywords: Opioids, Primates, SIB, Stress
Publication Number: 10270861
ISBN: 978-0-355-52036-1
Copyright © 2020 ProQuest LLC. All rights reserved. Terms and Conditions Privacy Policy Cookie Policy