Posttranslational Processing of Peptide Precursors to Fragments -- Peptides -- Immunocytochemical Techniques in Peptide Localization -- In Vivo and In Vitro Studies on Peptide Release -- Functional Identification of Peptide Receptors -- Identification of Neuropeptide Receptors -- Biochemical Approaches to the Study of Peptide Actions -- Behavioral Tests -- Integrative Physiological Studies of Peptides in the Central Nervous System -- In Vivo Electrophysiological Techniques in the Study of Peptidergic Neurons and Actions -- In Vitro Preparations for Electrophysiological Study of Peptide Neurons and Actions -- Molluscan Model Systems for the Study of Neuropeptides.