Acid-Base Regulation and Ammonia Elimination.- 1 pH Homeostasis in Terrestrial Vertebrates; Ammonium Ion as a Proton Source.- 1 Introduction.- 2 Renal Glutamine Metabolism.- 3 Catabolism of Protein Generates Bicarbonate.- 4 Disposal of Metabolic Bicarbonate.- 5 Summary.- References.- 2 Renal Transport of Organic Acids and Bases in Non-Mammalian Vertebrates.- 1 Introduction.- 2 Organic Acids (or Anions).- 3 Organic Bases (or Cations).- References.- 3 pH Homeostasis in Terrestrial Vertebrates: A Comparison of Traditional and New Concepts.- 1 Introduction.- 2 Nutrients and Acid-Base Status.- 3 Renal Ammonium and Net Acid Excretion.- 4 Conclusions and Summary.- References.- 4 Ammonia vs Ammonium: Elimination Pathways of Nitrogenous Wastes in Ammoniotelic Fishes.- 1 Introduction.- 2 Production, Ionization and Partial Pressure.- 3 Aqueous Diffusion.- 4 Transfer of Ammonia Across Cell Membranes.- 5 Elimination of Ammonia from the Body Fluids.- 6 Conclusions.- References.- Ion Transfer Processes.- 5 Morphological Basis of Acid-Base and Ionic Regulation in Fish.- 1 Introduction.- 2 Ionic Regulation.- 3 Acid-Base Regulation.- References.- 6 The Roles of Natriuretic Peptide Hormones in Fish Osmoregulation and Hemodynamics.- 1 Introduction.- 2 Biochemistry of Natriuretic Peptide Hormones in Mammals.- 3 Physiology of Natriuretic Peptide Hormones in Mammals.- 4 Physiology of Fish Osmoregulation.- 5 Endocrine Control of Fish Osmoregulation.- 6 Evidence for Role of Natriuretic Peptide Hormones in Fish Osmoregulation.- 7 Conclusions.- References.- 7 Regulation of Ion and Water Transport by Hydrogen Ions in High Resistance Epithelia.- 1 Introduction.- 2 Intracellular pH: A Cross-Talk Signal in Principal Cells.- 3 Regulation of K+ Channel Activity by Intracellular ATP: ADP.- 4 Regulation of K+ Channel Activity by Intracellular Ca2+.- 5 Proton Permeability in Anti-Diuretic-Hormone-Induced Channels.- 6 Cellular Transport Pathways for Na+ Absorption and H+ Secretion.- 7 Conclusions.- References.- 8 Intracellular Signals Controlling Ionic and Acid-Base Regulation in Avian Nasal Gland Cells.- 1 Introduction.- 2 Secretory Mechanism.- 3 Signals for Secretion.- 4 Metabolism and Intracellular pH.- 5 Muscarinic Receptor Characterization.- 6 Proliferation and Differentiation Responses.- 7 Conclusions.- References.- Hypoxia and Metabolic Adaptation.- 9 Interrelationships Between Hypoxia and Thermoregulation in Vertebrates.- 1 Introduction.- 2 Hypoxia and Thermoregulation.- 3 Other Stresses and Thermoregulation.- 4 Conclusions.- References.- 10 Sulfide Tolerance in Marine Invertebrates.- 1 Introduction.- 2 Sediment.- 3 Living System.- 4 Sulfide Tolerance.- 5 Conclusion.- References.