Prologue.- Introducing the VIDM Club.- A Beautiful Molecule.- 1. Introduction: The Origins of Nitric Oxide.- Nitrogen Cycles.- Sources of Nitric Oxide, an Air Pollutant.- Use of Nitric Oxide as a Paramagnetic Probe of Metalloproteins.- Nitric Oxide in Bacterial Denitrification.- Effects of Exogenous Nitric Oxide on Humans.- Nitric Oxide Biosynthesis in Mammals.- Introductory Chapters.- Scaling Problems in the Quantification Methods of Nitric Oxide.- A Historical Note.- Additional Recent Bibliography.- 2. Basic Chemistry of Nitric Oxide and Related Nitrogen Oxides....- Structure of Nitrogen Oxides.- Reactivity of Nitric Oxide and Nitrogen Oxides.- 3. Basic EPR Methodology.- Basic Principles of EPR Spectroscopy.- Experimental Conditions.- Discussion: Specificity Versus Sensitivity.- 4. EPR Characterization of Nitric Oxide Binding to Hemoglobin.- Nitrosyl Hemoglobin: Kinetic and EPR Data.- Reactions of Nitric Oxide with Ferrihemoglobin and Oxyhemoglobin.- Conclusion.- 5. Effects of Nitric Oxide on Red Blood Cells.- Effects of Long-Term Exposure of Animals and Humans to Nitric Oxide and Nitrogen Dioxide Gas Considered as Air Pollutants.- Effects of Nitrite and Nitrogenous Vasodilators on Red Blood Cells.- Effects on Red Blood Cells of Nitric Oxide Inhalation in Therapeutic Uses.- Conclusions.- 6. Utilization of Nitric Oxide as a Paramagnetic Probe of the Molecular Oxygen Binding Site of Metalloenzymes.- Hemoproteins.- Cytochrome c Oxidase (Cytochrome aa3).- Copper-Containing Proteins.- Mononuclear Iron-Containing Dioxygenases.- [FeS], Ni and Mo Cluster-Containing Proteins.- Binuclear Iron-Containing Proteins.- Conclusion.- 7. Nitric Oxide, an Intermediate in the Denitrification Process and Other Bacterial Pathways, as Detected by EPR Spectroscopy.- Introduction: A Historical Background.- Respiratory and Assimilatory Nitrite Reductases.- Nitric Oxide Reductases.- Other Cytochromes Interacting with Nitric Oxide.- Nitrous Oxide Reductases.- Possible Roles of Nitric Oxide in Nitrification and Nitrogen-Fixation.- Bacterial Nitric Oxide Synthase.- Discussion and Conclusion.- 8. Nitric Oxide Biosynthesis in Mammals.- Constitutive and Inducible Nitric Oxide Synthases.- Enzymatic Mechanism of Nitric Oxide Synthases.- Nitric Oxide Synthases' Regulations.- Post-Transcriptional Modifications of the Enzyme.- Conclusion.- 9. The Use of EPR Spectroscopy for the Identification of the Nature of Endothelium-Derived Relaxing Factor.- The Nature of Endothelium-Derived Relaxing Factor: A Controversy.- Nitric Oxide as an EDRF Detected by EPR Spectroscopy.- Fe(SR)2(NO)2 Ternary Iron Complexes as Plausible EDRF or Nitric Oxide Transporters.- Conclusion.- 10. Enzymatic Targets of Nitric Oxide as Detected by EPR Spectroscopy Within Mammal Cells.- Soluble Guanylate Cyclase.- [FeS] Cluster-Containing Enzyme.- Ribonucleotide Reductase.- Proteins of the Iron Metabolism.- Conclusion.- 11. Overproduction of Nitric Oxide in Physiology and Pathophysiology: EPR Detection.- Cancer and Interleukin-2 Immunotherapy.- Parasites, Fungi and Bacterial Infections.- Septic Shock.- Autoimmune Diseases.- Organ Transplantations.- Vascular Diseases.- Other Physiological and Pathophysiological States.- Conclusion.- 12. Palliatives to Underproduction of Nitric Oxide as Assayed by EPR Spectroscopy.- Metal Complexes as Nitric Oxide Donors.- Nitrite, Organic Nitrites and Nitrates.- Other Derivatives.- Inhalation Of Nitric Oxide: NO Gas, a Suppletive Drug.- Conclusion.- 13. Nitric Oxide-Specific Spin-Trapping EPR Methods.- Use of Hemoglobin as a Nitric Oxide Spin-Trap.- Conventional Spin-Trapping.- Prospects on Nitric Oxide-Specific Spin-Traps.- Scavenging of Nitric Oxide by Reaction with Stable Free Radicals.- Line Broadening of Fusinite and Other Free Radicals by Nitric Oxide.- Use of Fe-(DETC)2 and Similar Complexes as Nitric Oxide Spin-Traps.- Conclusion.- 14. General Discussion: Crossregulations of Metalloenzymes Triggered by Nitric Oxide.- Downregulation of Nitric Oxide Synthase by Nitric Oxide.- Inhibition of Microsomal Cytochromes P-450.- The Urea Cycle.- Inhibition or Regulation of Cytochrome c Oxidase.- Crossregulations of Other Inducible Metalloproteins.- Regulation by Nitric Oxide of Other Metalloenzymes of the Inflammatory Response.- Other Targets.- General Conclusion.