Preface. Structure and Function of H,K-ATPASE - Molecular Basis for Drug Targets. 1. The Gastric H,K-ATPase; O. Vagin, et al. 2. Human Nongastric H,K-ATPase: Current View On Structure and Functional Properties; G. Adams, et al. 3. Functional Consequences of Subunit Interactions in Na,K- and H,K-ATPases; G. Crambert, et al. 4. HKcalpha Encodes Ouabain-Insensitive H,K-ATPase in Surface Cells of Rat Distal Colon; H.J. Binder. 5. Molecular Diversity and Regulatory Heterogeneity of H,K-ATPases in Kidney; T.D. Dubose, et al. 6. Mutational Analysis of Gastric Proton Pump, alpha- and beta-Subunits; S. Asano, et al. 7. Structure-Activity Relationships of Na,K-ATPase, and H,K-ATPase; J.J.H.H.M. de Pont, et al. 8. The Effect of Mutations Within a Cluster of Homologous Amino Acids Present in the M5, M6 and M8 Transmembrane Regions of the H,K-ATPase; E.C. Rabon, et al. 9. Host-Specific H. pylori Inhibition of H,K-ATPase alpha Subunit Gene Expression; A. Smolka, M. Göõz. 10. H+,K+-ATPase, the Dominant Gastric Autoantigen In Helicobacter pylori Infection; B.J. Appelmelk, et al. 11. The Gastric H/K ATPase in the Pathogenesis of Autoimmune Gastritis; B.-H. Toh, et al. 12. Duodenal Protection: Influence of Melatonin and Other Intestinal Transmitters on Duodenal Bicarbonate Secretion and Enterocyte Signaling; G. Flemström, M. Sjöblom. 13. Role of Cytokines in Helicobacter pylori-Induced Gastric Epithelial Cell Matrix Metalloproteinase Secretion and Activation; M. Gööz, et al. 14. HCl Causes LessIntracellular Acidification in Surface Epithelial Cells of Necturus Gastric Mucosa than Other Inorganic Acids; T. Kiviluoto, et al. 15. Ethanol Increases Intracellular Free Calcium, Closes Gap Junctions and Decreased Cell Volume in Primary Cultured Rabbit Gastric Epithelial Cell Monolayers; E. Kivilaakso, et al. 16. Induction of Small Intestinal Damage by Inhibition of Both NO Synthase and COX-2; A. Tanaka, et al. 17. Role of Protein Kinases on Acid-Induced Duodenal Bicarbonate Secretion in Rats; O. Furukawa, et al. 18. Acid Induces Duodenal Epithelial Acidification and HCO3-Secretion via Activation of the Na+:HCO3-Cotransporter and CFTR in Mice; M. Hirokawa, et al. Gene Targeting Mouse &endash; Mechanisms of Acid Secretion and Cell Proliferation. 19. Insights into the Cell Biology, Development and Pathology of the Gastric Mucosa Revealed in Gastric H/K ATPase and Gastrin-Deficient Mice; I. van Driel, et al. 20. Genetically Engineered Animal Model: Physiological Studies with Gastrin in Transgenic Mice; G.J. Dockray, et al. 21. Gastric Cytoprotection by Prostaglandin E2 &endash; Relation to EP Receptor Subtypes; K. Takeuchi, et al. 22. Gastric Mucus Accumulation is Reduced in Helicobacter pylori Infected Transgenic Mice Expressing the Human α1,3/4-Fucosyltransferase in Surface Epithelial Cells; J. Henriksnäs, et al. Signal Transduction in the Parietal Cell &endash; Pathway to Activation. 23. New Insights into Second Regulation of Parietal Cell Function by Novel Downstream Signaling Proteins; C.S. Chew, et al. 24.