Neurotoxins That Affect Central and Peripheral Catecholamine Neurons.- Neurotoxins that affect central indoleamine neurons.- Toxins Affecting Cholinergic Neurons.- GABA Antagonists.- Specificity of Drugs as Tools in Psychopharmacology.- Determination of Monoamine Turnover by Blockade of Their Synthesis or Metabolism.- Dopamine Receptors and Neuroleptic Drugs.- Use of 5-HT Receptor Agonists and Antagonists for the Characterization of Their Respective Receptor Sites.- Biochemical Models of Parkinson's Disease.- Drug-Induced Behavioral Models of Central Disorders.- Determination of Acetylcholine Dynamics.