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Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION to ETHANOL and WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE

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University of Kentucky UKnowledge Theses and Dissertations--Psychology Psychology 2015 Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION TO ETHANOL AND WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE Anna R. Reynolds Univerity of Kentucky, [email protected] Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Reynolds, Anna R., "Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION TO ETHANOL AND WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE" (2015). Theses and Dissertations--Psychology. 74. https://uknowledge.uky.edu/psychology_etds/74 This Doctoral Dissertation is brought to you for free and open access by the Psychology at UKnowledge. It has been accepted for inclusion in Theses and Dissertations--Psychology by an authorized administrator of UKnowledge. For more information, please contact [email protected]. STUDENT AGREEMENT: I represent that my thesis or dissertation and abstract are my original work. Proper attribution has been given to all outside sources. I understand that I am solely responsible for obtaining any needed copyright permissions. I have obtained needed written permission statement(s) from the owner(s) of each third-party copyrighted matter to be included in my work, allowing electronic distribution (if such use is not permitted by the fair use doctrine) which will be submitted to UKnowledge as Additional File. I hereby grant to The University of Kentucky and its agents the irrevocable, non-exclusive, and royalty-free license to archive and make accessible my work in whole or in part in all forms of media, now or hereafter known. I agree that the document mentioned above may be made available immediately for worldwide access unless an embargo applies. I retain all other ownership rights to the copyright of my work. I also retain the right to use in future works (such as articles or books) all or part of my work. I understand that I am free to register the copyright to my work. REVIEW, APPROVAL AND ACCEPTANCE The document mentioned above has been reviewed and accepted by the student’s advisor, on behalf of the advisory committee, and by the Director of Graduate Studies (DGS), on behalf of the program; we verify that this is the final, approved version of the student’s thesis including all changes required by the advisory committee. The undersigned agree to abide by the statements above. Anna R. Reynolds, Student Dr. Mark A. Prendergast, Major Professor Dr. David E. Berry, Director of Graduate Studies Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION TO ETHANOL AND WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE DISSERTATION Dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Arts and Sciences at the University of Kentucky By Anna R. Reynolds Lexington, Kentucky Director: Dr. Mark A. Prendergast, Professor of Psychology Lexington, Kentucky 2015 Copyright ©Anna R. Reynolds 2015 ABSTRACT OF DISSERTATION Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION TO ETHANOL AND WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE Prolonged, heavy consumption of alcohol produces marked neuroadaptations in excitatory neurotransmission. These effects are accelerated following patterns of intermittent heavy drinking wherein periods of heavy consumption are followed by periods of abstinence. Studies have shown that neuroadaptive changes in the glutamatergic N-methyl-D-aspartate (NMDA) receptor produces excitotoxicity during periods of withdrawal; however, upstream targets were not adequately characterized. The present studies sought to identify these targets by assessing the role of group 1 metabotropic glutamate receptors (mGluR) and intracellular calcium in promoting cytotoxicity of hippocampal cell layers in vitro. It was hypothesized that ethanol-induced activity of mGluR1-and-5 contributes to hippocampal cytotoxicity and promotes the behavioral effects of withdrawal in vivo. In order to identify and test this theory, rat hippocampal explants were co-exposed to chronic intermittent ethanol exposure with or without the addition of a group 1 mGluR antagonist to assess cytotoxicity in neuronal cell types. In a second study, adult male rodents were co-exposed to chronic intermittent ethanol exposure with or without the addition of an mGluR5 antagonist to assess the role of these receptors in the development of dependence as reflected in withdrawal behaviors. Together, these studies help to identify and screen toxicity of putative pharmacotherapies for the treatment of ethanol dependence in the clinical population. KEYWORDS: ethanol dependence, metabotropic glutamate receptors, intracellular calcium, signal transduction _ Anna R. Reynolds____________ Student’s Signature __7/5/15____________________ Date Gαq-ASSOCIATED SIGNALING PROMOTES NEUROADAPTATION TO ETHANOL AND WITHDRAWAL-ASSOCIATED HIPPOCAMPAL DAMAGE By Anna R. Reynolds __Mark A. Prendergast____________ Director of Dissertation ____David Berry_________________ Director of Graduate Studies _______7/05/15__________________ Date For Holden Robert ACKNOWLEDGEMENTS The following dissertation, while an individual work, benefited from the insights and direction of several people. First, my Dissertation Chair, Dr. Mark Prendergast, exemplifies the high quality scholarship to which I aspire. Next, I wish to thank the complete Dissertation Committee and outside reader respectively: Dr. Craig Rush, Dr. Michael Bardo, Dr. Nada Porter, and Dr. Richard Grondin. Each individual provided insights that guided and challenged my thinking, substantially improving the finished product. This research is supported by Grant AA013388 from the National Institute on Alcohol and Alcoholism (NIAAA) awarded to MAP and DA035200 from the National Institute on Drug Abuse (NIDA). iii Table of Contents ACKNOWLEDGEMENTS ............................................................................................................ iii LIST OF FIGURES ......................................................................................................................... vi CHAPTER ONE: General Introduction ........................................................................................... 1 1.1. Background and Significance ................................................................................................ 1 1.2. Alcohol Withdrawal: Effects on Brain and Behavior ............................................................ 4 CHAPTER TWO: Study One: Protein Kinase Activation and Cytotoxicity of Intermittent Ethanol in Vitro .............................................................................................................................................. 8 2.1. Introduction ........................................................................................................................... 8 2.2. Experimental Rationale ......................................................................................................... 9 2.3. Methods ............................................................................................................................... 10 2.4. Results ................................................................................................................................. 14 2.5. Discussion ............................................................................................................................ 15 CHAPTER THREE: Study Two: Effects of Chronic, Intermittent Ethanol on Withdrawal Behavior and Working Memory in Vivo ........................................................................................ 28 3.1. Introduction ......................................................................................................................... 28 3.2. Experimental Rationale ....................................................................................................... 30 3.3. Methods ............................................................................................................................... 31 3.4. Results ................................................................................................................................. 35 3.5. Discussion ............................................................................................................................ 38 CHAPTER FOUR: Study Three: Influence of mGluR1/5-containing Receptors and Intracellular Calcium in Development of Ethanol Dependence in Vitro ............................................................ 59 4.1. Introduction ......................................................................................................................... 59 4.2. Experimental Rationale ....................................................................................................... 62 4.3. Methods ............................................................................................................................... 62 4.4. Results ................................................................................................................................. 66 4.5. Discussion ............................................................................................................................ 69 CHAPTER FIVE: Influence of mGluR5-containing Receptors in the Development of Ethanol Dependence In Vivo ........................................................................................................................ 97 5.1. Introduction ........................................................................................................................
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