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Functional Organization of the Gustatory System in The Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1986 Functional Organization of the Gustatory System in the Brains of Ictalurid Catfish: a Combined Electrophysiological and Neuroanatomical Study (Taste, Viscerotopic, Sensory Maps, Forebrain). Jagmeet Singh Kanwal Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Kanwal, Jagmeet Singh, "Functional Organization of the Gustatory System in the Brains of Ictalurid Catfish: a Combined Electrophysiological and Neuroanatomical Study (Taste, Viscerotopic, Sensory Maps, Forebrain)." (1986). LSU Historical Dissertations and Theses. 4244. https://digitalcommons.lsu.edu/gradschool_disstheses/4244 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS This reproduction was made from a copy of a manuscript sent to us for publication and microfilming. While the most advanced technology has been used to pho­ tograph and reproduce this manuscript, the quality of the reproduction is heavily dependent upon the quality of the material submitted. Pages in any manuscript may have indistinct print. In all cases the best available copy has been filmed. The following explanation of techniques is provided to help clarify notations which may appear on this reproduction. 1. Manuscripts may not always be complete. When it is not possible to obtain missing pages, a note appears to indicate this. 2. When copyrighted materials are removed from the manuscript, a note ap­ pears to indicate this. 3. Oversize materials (maps, drawings, and charts) are photographed by sec­ tioning the original, beginning at the upper left hand comer and continu­ ing from left to right in equal sections with small overlaps. Each oversize page is also filmed as one exposure and is available, for an additional charge, as a standard 35mm slide or in black and white paper format.* 4. Most photographs reproduce acceptably on positive microfilm or micro­ fiche but lack clarity on xerographic copies made from the microfilm. Fbr an additional charge, all photographs are available in black and white standard 35mm slide format.* *For more information about black and white slides or enlarged paper reproductions, please contact the Dissertations Customer Services Department. T TA/T-T Dissertation L J 1 V 1 1 Information Service University Microfilms International A Bell & Howell Information Company 300 N. Zeeb Road, Ann Arbor, Michigan 48106 8629178 Kanwal, Jagm eet Singh FUNCTIONAL ORGANIZATION OF THE GUSTATORY SYSTEM IN THE BRAINS OF ICTALURID CATFISH: A COMBINED ELECTROPHYSIOLOGICAL AND NEUROANATOMICAL STUDY Thf5 Louisiana State University and Agricultural and Mechanical Ph.D. Col. 1986 University Microfilms International 300 N. Zeeb Road, Ann Arbor, Ml 48106 PLEASE NOTE: In all cases this material has been filmed in the best possible way from the available copy. Problems encountered with this document have been identified here with a check mark V_ 1. Glossy photographs or pages.J 2. Colored illustrations, paper or print_______ 3. Photographs with dark background> / 4. Illustrations are poor copy_______ 5. Pages with black marks, not original copy _ _ * / 6. Print shows through as there is text on both sides of page. 7. Indistinct, broken or small print on several pages_________ 8. Print exceeds margin requirements 9. Tightly bound copy with print lost in spine________ 10. Computer printout pages with indistinct print________ 11. Page(s) _____________lacking when material received, and not available from school or author. 12. Page(s)_____________seem to be missing in numbering only as text follows. 13. Two pages numbered . Text follows. 14. Curling and wrinkled pages_______ 15. Dissertation contains pages with print at a slant, filmed as received. 16. Other _______________ University Microfilms International FUNCTIONAL ORGANIZATION OF THE GUSTATORY SYSTEM IN THE BRAINS OF ICTALURID CATFISH:. A combined electrophysiological and neuroanatomical study A Dissertation submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physiology by Jagmeet S. Kanwal B.Sc.(hons.), Delhi University, 1977 B.S.(hons. sch.), Guru Nanak Dev University, 1979 M.S., Louisiana State University, 1982 May 1986 DEDICATED to the 'hard working breed' of graduate students Much is the hope, And many a despair. An everlasting scope And opportunities so rare. ii ACKNOWLEDGEMENTS I am thankful to my thesis advisor, Dr. John Caprio, for always lending a big helping hand and providing all the necessary guidance on issues relating to as well as extending beyond the realm of science. 1 am also grateful to Dr. Thomas Finger for his constant encouragement from afar as well as during my eventful trips to Denver. This thesis is evidence of the marks left on me by the infectious nature of his bubbling enthusiasm for neuroanatomy. My gratitude also extends to all of the remaining members of my committee, Drs. George Strain, Dennis Duffield, Albert Meier, Michael Fitzsimons and Harold Silverman, for their useful suggestions and who along with my other teachers succeeded in imparting precious knowledge and increasing my awareness of the varied aspects of research in the biological sciences. To Dr. Takayuki Marui, I thank for initiating and encouraging me in my exploration■of the complexities of the vertebrate central nervous system by means of electrophysiological techniques. I am especially indebted to Dr. Dominique Homberger for all those inspiring and thought provoking discussions which form the backbone of good scientific research. I feel great pleasure in acknowledging the critical role played by my friends and family who were instrumental to the progress of this work in many different ways. Without the help and companionship of my colleagues, past and present, at L.S.U. it would have been difficult to mix the pleasure with business. Their antics and attitudes added ill another dimension to graduate study and their memory will continue to bring a smile on my face. My family's constant moral support was, without doubt, the single big factor which helped me overcome many a hardship during the course of this study. Eventually, my acquaintance with Mini towards the later stages of this study gave a new meaning to research and provided the much needed 'second wind' to complete my research projects. TABLE OF CONTENTS Page ACKNOWLEDGEMENTS iii LIST OF TABLES vii LIST OF FIGURES viii ABSTRACT xiv GENERAL INTRODUCTION ......................................... I REFERENCES ......................................... 7 CHAPTER 1 Abstract ......................................... 11 Introduction.......... ..................... ....................12 Materials and Methods ............................ ............ 17 Results ................................ ......... 20 Discusssion........... ........... ............................. 41 References ........ ................. .............. 53 CHAPTER 2 Abstract ......................................... 62 Introduction.......... ......................................... 63 Materials and Methods ......................................... 66 Results ......................................... 69 Discusssion .........................................81 References ......................................... 88 CHAPTER 3 Abstract ......................................... 95 Introduction.......... .......... .............................. 96 Materials and Methods ......................................... 98 Results 103 v vi Discusssion . 144 References 156 GENERAL SUMMARY 166 APPENDIX . 169 Abstract '...... 171 Introduction 172 Materials and Methods .......................................... 174 Results 176 Discusssion 186 References 193 VITA 198 LIST OF TABLES Table Page CHAPTER 1 1. Correlation of visceral information in the catfish brainstem. ........................ .................... 49 APPENDIX 1. Response characteristics of taste nerves in the channel catfish................................................... 189 vii LIST OF FIGURES Figure Page INTRODUCTION 1. Schematic representation to show differences between the extra-oral and oral taste systems in ictalurid catfishes. ...... 3 CHAPTER 1 ' 1. Pattern of innervation of the glossopharyngeus (IX) and the vagus (X) nerve in the oro-pharyngeal region of the channel catfish. ...... 16 2. Central proj ection pattern of the glossopharyngeal nerve root in the rostral part of the vagal lobe and in theregion of the nIF.............. ...... 22 3. (a) Photomicrograph of a transverse section showing HRP labelled glossopharyngeal fibers in the region of the nIF. ...... 25 (b) Photomicrograph of a transverse section showing HRP labelled fibers of the glossophyaryngeal nerve coursing alongside the internal arcuate fibers in the facial lobe. ...... 25 4. Central projection pattern of the vagal branches viii ix VN2 and IVN in the medulla of the catfish. 27 5. Photomicrographs of terminations in the dorsal cap region (DC) of the vagal lobe of (a) the branchial branch VN3, and (b) VN5 of the vagus labelled with HRP......... 29 6. HRP labelled fibers
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