CHAPTER TWENTY-SIX Examining Nitroxyl in Biological Systems Jon M. Fukuto,* ,† Matthew I. Jackson, † Nina Kaludercic, ‡ and Nazareno Paolocci ‡,§ Contents 1. Introduction 412 2. Nitroxyl Donors 412 2.1. General considerations 413 2.2. Angeli’s salt 414 2.3. Sulfohydroxamic acids and derivatives (Piloty’s acid) 416 2.4. Cyanamide 417 2.5. Other HNO donors amenable to biological studies 417 3. Biological HNO Chemistry 419 3.1. General considerations 419 3.2. Kinetics 420 3.3. Sites of HNO reactivity 421 4. Use of HNO Donors in Biological Studies 423 5. Nitroxyl Pharmacological Effects: In Vivo and In Vitro Studies 424 5.1. Nitroxyl in the cardiovascular system 424 5.2. Nitroxyl and myocardial ischemia/reperfusion injury 425 5.3. Nitroxyl donors in Vivo can trigger the release of peptides from the nonadrenergic noncholinergic system 425 5.4. Nitroxyl and the nervous system: Physiological and toxicological effects 426 6. Summary 426 References 427 Methods in Enzymology, Volume 440 # 2008 Elsevier Inc. ISSN 0076-6879, DOI: 10.1016/S0076-6879(07)00826-9 All rights reserved. * Department of Pharmacology, UCLA School of Medicine, Center for the Health Sciences, Los Angeles, California { Interdepartmental Program in Molecular Toxicology, UCLA School of Public Health, Los Angeles, California { Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, Maryland } Department of Clinical and Experimental Medicine, General Pathology and Immunology Section, University of Perugia, Perugia, Italy 411