by Poon Chuen Wai. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 161-176). / Abstract --- p.i / Acknowledgements --- p.vi / Abbreviations --- p.viii / Introduction --- p.1 / Review of the literature --- p.2 / Incidence and historical background --- p.3 / Theories on etiology of emesis/hyperemesis gavidarum --- p.5 / Mechanism of vomiting --- p.7 / Temporal association between hCG and emesis/hyperemesis gravidarum --- p.9 / Thyroid function and emesis/hyperemesis gravidarum --- p.13 / Steroid hormone and emesis/hyperemesis gravidarum --- p.15 / Hyperemesis caused by corpus luteum in right ovary --- p.15 / "Formulation of a new hypothesis for emesis/hyperemesis gravidarum : “hCG stimulated electrolyte and fluid secretion in the UGIT, leading to pregnancy associated vomiting 226}0ح" --- p.16 / Is hCG a humoural secretory agent ？ --- p.18 / Can hCG stimulate the secretion of fluid and electrolytes from the GIT ？ --- p.18 / Are LH-CGR present in the GIT ？ --- p.20 / Can electrolyte and fluid secretion in the UGIT lead to vomiting during pregnancy ？ --- p.24 / HCG and regulation of electrolyte and fluid movement --- p.24 / Gut- gonad axis --- p.25 / Objectives --- p.27 / Section 1 hCG and in vitro secretion of anions from cells with functional LH-CGR - A cell model --- p.28 / Introduction --- p.28 / Materials and Methods / Materials --- p.30 / Methods / Chapter 1. --- Test for the presence of LH-CGR in human gastrointestinal cell lines --- p.31 / Chapter 2. --- Establishment of cells expressing functional receptor for hCG --- p.35 / Chapter 3. --- Effect of hCG on [125I] iodide efflux from COS-1 cells transiently expressing MC1+2 LH-CG/TSH chimera receptor --- p.38 / Chapter 4. --- Anion secretion from MLTC-1 cells with wild type LH-CGR --- p.38 / Chapter 5. --- Statistics --- p.41 / Results --- p.42 / Discussion --- p.55 / Section 2 Presence of LH-CGR in the upper gastrointestinal tract of rat --- p.61 / Introduction --- p.61 / Materials and Methods / Materials --- p.62 / Methods / Chapter 1. --- Screening for hCG binding sites along the rat GIT --- p.63 / Chapter 2. --- Detection of Triton X-100 soluble plasma membrane hCG binding protein along the rat GIT --- p.64 / Chapter 3. --- Measurement of affinity of the hCG binding proteins by Scatchard analysis --- p.66 / Chapter 4. --- Determination of the isoelectric points for the duodenal hCG binding protein and ovarian LH-CGR --- p.67 / Chapter 5. --- Developement of antibodies to LH-CGR --- p.69 / Chapter 6. --- Western blotting to determine the molecular weight of the LH-CGR --- p.78 / Chapter 7. --- Immunohistochemical localization of LH-CGR in the UGIT --- p.80 / Chapter 8. --- Statistics --- p.81 / Results --- p.82 / Discussion --- p.109 / Section 3 hCG and in vivo secretion of electrolytes from pancreas / duodenal region in rats --- p.119 / Introduction --- p.119 / Materials and Methods / Materials --- p.121 / Methods --- p.121 / Chapter 1. --- The effect of hCG on the secretion of electrolytes into bile and pancreatic/duodenal effluent --- p.121 / Chapter 2. --- Effect of ovariectomy on pancreatic content and electrolyte levels in blood --- p.125 / Chapter 3. --- Statistics --- p.128 / Results --- p.129 / Discussion --- p.151 / General discussion --- p.155 / Reference --- p.161 / Original data --- p.176