NEUROSCIENCE
ROLE OF α2A ADRENERGIC RECEPTORS IN EXTINCTION OF POSITIVE AND NEGATIVE VALENCE LEARNED BEHAVIORS
Adeola R. Davis
Dissertation under the direction of Professor Danny Winder
The work presented in this dissertation focuses on the role of α2 adrenergic receptors in extinction of positive and negative valence learned behaviors as well as investigating the mechanism of the action of a pharmaceutical agent, yohimbine.
Mechanisms underlying extinction of positive valence associations such as drug self administration and place preference are poorly understood, yet may have important relevance to addiction treatment. Data suggest a major role for the noradrenergic system in extinction of fear-based learning. Administration of yohimbine, an α2 adrenergic receptor antagonist, facilitates extinction of learned fear. Employing a combination of pharmacological and genetic approaches, we investigated the role of the α2 adrenergic receptor in extinction of cocaine-induced conditioned place preference and lithium chloride-induced conditioned place aversion. Additionally, yohimbine is a commonly used pharmaceutical agent and the mechanism of action is often attributed to solely antagonism at the α2 adrenergic receptors. However, we investigate potential off target sites using electrophysiological methods.
In this research, the results indicate that extinction of conditioned place preference with yohimbine occurs independently of the α2 adrenergic receptors although the receptors modify the effect. Further, extinction with yohimbine of conditioned place preference and conditioned place aversion similarly impairs extinction of the behaviors. Lastly, we found a novel target for extinction behaviors with the use of electrophysiology.
| Identifer | oai:union.ndltd.org:VANDERBILT/oai:VANDERBILTETD:etd-06242009-204012 |
| Date | 25 June 2009 |
| Creators | Davis, Adeola Ronke |
| Contributors | Aurelio Galli, Gregg Stanwood, Danny Winder, Craig Kennedy |
| Publisher | VANDERBILT |
| Source Sets | Vanderbilt University Theses |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.library.vanderbilt.edu/available/etd-06242009-204012/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Vanderbilt University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
Page generated in 0.0094 seconds