Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2012 Cellular Responses to Osmotic Perturbation: A High-Field ¹H and ²³Na Magnetic Resonance Microscopy Study John Walsh Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ENGINEERING CELLULAR RESPONSES TO OSMOTIC PERTURBATION: A HIGH-FIELD 1H AND 23Na MAGNETIC RESONANCE MICROSCOPY STUDY By JOHN WALSH A Thesis submitted to the Department of Chemical and Biomedical Engineering in partial fulfillment of the requirements for the degree of Master of Science Degree Awarded: Fall Semester, 2012 John Walsh defended this thesis on August 10, 2012. The members of the supervisory committee were: Samuel C. Grant Professor Directing Thesis Teng Ma Committee Member Jingjiao Guan Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the thesis has been approved in accordance with university requirements. ii This thesis is dedicated to my family and friends who have continued to support me through this long process. I couldn’t have done it without you. iii ACKNOWLEDGEMENTS I would first like to acknowledge the FAMU-FSU College of Engineering and the National High Magnetic Field Laboratory for use of their facilities to perform this work. Only with access to these high magnetic fields could a project of this nature have been undertaken. I would also like to acknowledge my supervising professor, Dr. Samuel C. Grant, as his knowledge of magnetic resonance imaging and RF coil design were critical in conducting the experiments and acquiring the high resolution images obtained. Additionally, my committee members Dr. Teng Ma and Dr. Jingjiao Guan provided much insight on the directions and results of this project. I would like to acknowledge Parastou Foroutan, a graduate student in Dr. Grant’s lab, who aided me with the initial sodium imaging and acquainted me with the techniques used throughout this project. Additionally, I would like to acknowledge Corey Falgas, another fellow graduate student, who aided in maintaining the animals used in this work. I would also like to thank my other colleagues Ihssan Masad, Jens Rosenberg, and Jose Muniz for their support, ideas, and help throughout the course of the project. Finally, funding for this project came from the American Heart Association (SE Division) and the FSU Department of Chemical and Biomedical Engineering. Additional funding came from the FSU Office of National Fellowships through an Undergraduate Research and Creative Activity Award. For all of these contributions, I am grateful. iv TABLE OF CONTENTS List of Tables ............................................................................................................................vii List of Figures ............................................................................................................................ ix Abstract .................................................................................................................................. xiii 1. INTRODUCTION .............................................................................................................. 1 2. BACKGROUND AND THEORY ...................................................................................... 4 2.1 Magnetic Resonance Imaging .................................................................................... 4 2.2 Cell Membranes and Osmosis .................................................................................. 12 2.3 Relation to Pathological Conditions ......................................................................... 14 2.4 Single Cell Models .................................................................................................. 17 2.5 Tissue Models .......................................................................................................... 20 2.6 Diffusion Multi-Compartment Modeling.................................................................. 22 2.7 Sodium MRI ............................................................................................................ 24 3. OBJECTIVES ................................................................................................................... 28 3.1 High-Field MRI ....................................................................................................... 28 3.2 Radiofrequency (RF) Coil Design ............................................................................ 30 3.3 Neural Ganglia Model System ................................................................................. 32 3.4 Osmotic Perturbation ............................................................................................... 33 3.5 Cell Viability ........................................................................................................... 34 4. METHODS ....................................................................................................................... 36 4.1 Neural Ganglia Preparation ...................................................................................... 36 4.2 Artificial Sea Water (ASW) Solutions ...................................................................... 38 4.3 MR Image Acquisition ............................................................................................. 43 4.4 Statistical Analysis................................................................................................... 50 5. RESULTS ......................................................................................................................... 52 5.1 1H/23Na Imaging of Fixed Ganglia ........................................................................... 52 5.1.1 Isotonic Fixed Ganglia ................................................................................. 52 5.1.2 Hypertonic Fixed Ganglia ............................................................................ 60 5.1.3 Hypotonic Fixed Ganglia.............................................................................. 67 5.1.4 Fixed Ganglia Summary ............................................................................... 74 5.2 1H/23Na Imaging of Viable and Nonviable Ganglia .................................................. 76 5.2.1 Isotonic Viable/Nonviable Ganglia ............................................................... 76 5.2.2 Hypertonic Viable/Nonviable Ganglia .......................................................... 85 5.2.3 Hypotonic Viable/Nonviable Ganglia ........................................................... 93 5.2.4 Viable/Nonviable Ganglia Summary .......................................................... 102 5.3 Comparison of Viable and Fixed Ganglia ............................................................... 106 v 6. DISCUSSION ................................................................................................................. 111 7. CONCLUSIONS AND FUTURE DIRECTIONS ........................................................... 118 References .............................................................................................................................. 121 Biographical Sketch ................................................................................................................ 135 vi LIST OF TABLES 1 Standard concentrations of key compounds in isotonic artificial sea water (ASW) ............ 38 2 Quantities of each component to make 1 L of ASW solutions of different tonicities .......... 42 1 3 Summary of MR acquisition parameters for the H spin echo T1 measurement .................. 45 1 4 Summary of MR acquisition parameters for the H spin echo T2 measurement .................. 46 1 5 Summary of MR acquisition parameters for the H gradient echo T2* measurement .......... 47 6 Summary of MR acquisition parameters for the 1H diffusion-weighted spin echo ADC measurement .................................................................................................................... 48 23 7 Summary of MR acquisition parameters for the Na 3D gradient echo T1 measurement ... 49 23 8 Summary of MR acquisition parameters for the Na 3D gradient echo T2* measurement .................................................................................................................... 50 9 Proton and sodium relaxation and diffusion measurements for the isotonic fixed ganglia .. 60 10 Proton and sodium relaxation and diffusion measurements for the hypertonic fixed ganglia ............................................................................................................................. 67 11 Proton and sodium relaxation and diffusion measurements for the hypotonic fixed ganglia ............................................................................................................................. 74 12 Summary of relaxation and diffusion trends in fixed ganglia at varying tonicities .............. 75 13 Proton relaxation and diffusion measurements for the isotonic viable ganglia .................... 84 14 Proton and sodium relaxation and diffusion measurements for the isotonic nonviable ganglia ............................................................................................................................. 84 15 Proton relaxation and diffusion measurements for the hypertonic viable ganglia ............... 92 16 Proton and sodium relaxation and diffusion