Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2017 Neuromodulation of Mitral Cells by Serotonin and GLP-1 Neurons in the Olfactory Bulb and the Consequences of Gene Deletion of Kv1.3 Zhenbo Huang Follow this and additional works at the DigiNole: FSU's Digital Repository. For more information, please contact [email protected] FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES NEUROMODULATION OF MITRAL CELLS BY SEROTONIN AND GLP-1 NEURONS IN THE OLFACTORY BULB AND THE CONSEQUENCES OF GENE DELETION OF KV1.3 By ZHENBO HUANG A Dissertation submitted to the Department of Biological Science in partial fulfillment of the requirements for the degree of Doctor of Philosophy 2017 Zhenbo Huang defended this dissertation on November 16, 2017. The members of the supervisory committee were: Debra Ann Fadool Professor Directing Dissertation Timothy M. Logan University Representative David M. Gilbert Committee Member Lisa C. Lyons Committee Member Zuoxin Wang Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the dissertation has been approved in accordance with university requirements. ii This work is dedicated to my parents, Shengding Huang and Heyin Tang, for their unconditional support throughout my life. Without them, I could not have achieved this. iii ACKNOWLEDGMENTS First, I would love to thank my mentor, Dr. Debra Ann Fadool, for her attention and guidance to various aspects of my Ph.D. training. With her hands-on teaching, I acquired solid patch-clamp technique. Her rigorous writing style has helped me to become a better writer. Her scientific think enabled me to do thorough science. She also serves as a role model for me in life. Her kindness and patience to everyone inspires me to do the same. I would also like to thank my Graduate Committee, Drs. David Gilbert, Lisa Lyons, Timothy Logan, and Zuoxin Wang for their insightful comments and suggestions to my research. I learned a lot from them. Thanks to post-docs, Dr. Nicolas Thiebaud and Dr. Erminia Fardone, and my fellow graduate students, Austin Schwartz, Brandon Chelette, Daniel Landi Conde, Dolly Al Koborssy, Genevieve Bell, and Kassandra Ferguson, and Louis Colling in the lab. They helped me both in scientific experiments and in daily life. With their help I made a relative easy and pleasant transition to live in a foreign country. Dr. James M. Fadool and his laboratory crew were also very helpful during my Ph.D. study. Last, but not least, I would like to thank all the faculty and staff in the Program in Neuroscience and in the Biological Science Department who helped me along the way. Their help made me feel at home and contributed to my achievements here at Florida State University. iv TABLE OF CONTENTS List of Tables ................................................................................................................................ vii List of Figures .............................................................................................................................. viii List of Abbreviations .......................................................................................................................x Abstract ......................................................................................................................................... xii 1. INTRODUCTION ......................................................................................................................1 1.1 Origin of Neuro-electricity and the Development Patch-clamp Technology .......................1 1.2 Introduction of Ion Channels and their Function ..................................................................5 1.3 Neuromodulation in the Olfactory Bulb ...............................................................................9 2. DIFFERENTIAL SEROTONERGIC MODULATION ACROSS THE MAIN AND ACCESSORY OLFACTORY BULBS ....................................................................................14 2.1 Introduction .........................................................................................................................14 2.2 Materials and Methods……………………………………………………………………16 2.3 Results. ................................................................................................................................21 2.4 Discussion ...........................................................................................................................36 3. THE MODULATION OF GLP-1 NEURONS IN THE OLFACTORY BULB ......................41 3.1 Introduction .........................................................................................................................41 3.2 Materials and Methods……………………………………………………………………43 3.3 Results. ................................................................................................................................49 3.4 Discussion ...........................................................................................................................55 4. OLFACTION AND ANXIETY IN KV1.3 KNOCK-OUT MICE: POSSIBLE APPLICATION IN ADHD.......................................................................................................60 4.1 Introduction .........................................................................................................................60 4.2 Materials and Methods……………………………………………………………………62 4.3 Results. ................................................................................................................................69 4.4 Discussion ...........................................................................................................................77 5. SUMMARY ..............................................................................................................................84 APPENDICES ...............................................................................................................................87 A. KV1.3 AND MITOCHONDRIA ...............................................................................................87 B. TESTING QUANTUM DOT-CONJUGATED DRUG ON BRAIN SLICE ...........................95 C. THE EFFECTS OF SHORT-TERM PRENATAL HIGH-FAT DIET ON OFFSPRINGS AND DAMS THEMSELVES ..................................................................................................96 D. ACUC APPROVAL LETTER ..................................................................................................99 v REFERENCES ............................................................................................................................100 BIOGRAPHIC SKETCH.............................................................................................................127 vi LIST OF TABLES 2.1 A comparison of intrinsic properties of mitral cells (MCs) in the main olfactory bulb (MOB) versus those in the accessory olfactory bulb (AOB) ................................................................21 3.1 Basic intrinsic properties of GLP-1 neurons in the olfactory bulb ..........................................50 C.1 Litter statistics comparing dams maintained on control- and high-fat diets ...........................98 vii LIST OF FIGURES 1.1 Basic model of the olfactory bulb neural network. ..................................................................11 2.1 Mitral cells in the main olfactory bulb (MOB MCs) largely exhibit an increase in action potential (AP) firing frequency in response to serotonin (5-HT) ............................................23 2.2 Quantitative analysis of the excitatory response of MOB MCs. .............................................24 2.3 Serotonin (5-HT) elicits direct excitation of MOB MCs. ........................................................26 2.4 5-HT-evoked excitation in MOB MCs is inhibited by 5-HT receptor antagonists that have subtype specificity. ..................................................................................................................27 2.5 Mitral cells in the accessory olfactory bulb (AOB MCs) predominantly exhibit a decrease in AP firing frequency in response to 5-HT ................................................................................28 2.6 AOB MCs are differentially inhibited by 5-HT, regardless of onset kinetics of the modulation. ..............................................................................................................................31 2.7 5-HT-evoked inhibition in AOB MCs responds differentially to gabazine. ...........................32 2.8 Slow-onset 5-HT modulation is sensitive to 5-HT2 receptor antagonists while rapid-onset is sensitive to 5-HT1 receptor antagonist in AOB MCs. ..............................................................34 2.9 Model of serotonergic modulation in two parallel processing pathways of the olfactory system. .....................................................................................................................................40 3.1 Representative current-clamp recording of a GLP-1 neuron. ..................................................50 3.2 Acetylcholine shows inhibitory effects on GLP-1 neurons. ....................................................51 3.3 Acetylcholine shows excitatory effects on GLP-1 neurons. ....................................................52 3.4 Cholecystokinin modulates the activity of GLP-1 neurons. ....................................................53 3.5 A subgroup of GLP-1 neurons responds