Session I Effects of Messengers on Membrane Receptors.- A Effects of Transmitters and Modulators.- 1. Interactions between Convergent Afferent Transmitter Systems.- 2. Interactions of Peptides and Monoamines in Central Neurons: Role of Second Messengers.- 3. Multiple Transduction Mechanisms for Dopamine D2 Receptors in Anterior Pituitary Cells.- 4. Receptor Reserves at ?2-adrenergic and Dopaminergic Autoreceptors.- B Effects of Trophic Factors and Gangliosides.- 5. Potentiation of NGF-mediated Effects of Laminin.- 6. Gangliosides as Modulators of Neuronotrophic Interactions.- 7. Influence of Gangliosides and Nerve Growth Factor on the Plasticity of Forebrain Cholinergic Neurons.- 8. Hippocampal Stimulation of Cholinergic Expression in Primary Cultures of Basal Forebrain Neurons.- C Effects of Neurosteroids and Classical Steroids.- 9. Neurosteroids: Pregnenolone and Dehydroepiandrosterone in the Brain.- 10. Estrogenic and Antiestrogenic Modulation of Neuronal Membrane Sensitivity.- 11. Effects of Estrogens on the Electrophysiological Properties of Neurons and Adenohypophyseal Cells: Interactions with Dopamine.- Session II Interactions between Receptors in the Membrane.- A Possible Interactions between Molecular and Supramolecular Entities in the Membrane.- 12. Receptor Modification and Receptor Disposition in Membranes.- 13. Membrane Phospholipid Metabolism and Transmitters.- 14. Allosteric Sites and Conformational Transitions of the Acetylcholine Receptor: Models for Short-term Regulation of Receptor Response.- 15. Chloride Channel Modulation at GABAergic Synapses in Primary Cultures of Cortical Neurons.- 16. Mechanisms of Receptor-coupled Signal Transduction.- 17. The Gi-protein as a Target for Receptor-Receptor Interactions.- B Interactions between Receptors in Synaptic Membranes in the Central Nervous System.- 18. On the Role of Receptor-Receptor Interactions in Synaptic Transmission: Biochemical and Autoradiographical Studies on the Interactions between ?2-adrenergic and Neuropeptide Y Receptors in the Nucleus Tractus Solitarius.- 19. Aspects on the Integrative Capabilities of the Central Nervous System: Evidence for ¿Volume Transmission¿ and its Possible Relevance for Receptor-Receptor Interactions.- 20. Radioautographic Approaches to the Study of Receptor-Receptor Interactions in the Central Nervous System.- 21. Long-term Receptor Regulation Induced by Denervation of Heterologous Afferent Fibers: Functional Significance.- 22. Interactions between Vasoactive Intestinal Peptide and Norepinephrine, Ergot Alkaloids and Prostanoids in Mouse Cerebral Cortex.- C Interactions between Membrane Receptors in Endocrine and Peripheral Organs.- 23. Multiple Transduction Mechanisms Activated by the Neuropeptide Somatostatin.- 24. Receptor Mediated Activation of Phospholipase A2: Arachidonic Acid and its Metabolites as Second Messengers.- 25. Interactions between the Modulator Adenosine and Classical Transmitters.- 26. Interactions between Neuropeptide Y and Noradrenaline Receptor Mechanisms in Sympathetic Vascular Control.- 27. New Paradigm: Autonomic Neurotransmission by Multiple Interaction between Sites Intermittently Secreting Single Mixed Quanta.- 28. Adenosine Triphosphate: ¿Pre-transmitter¿, Co-transmitter or Modulator at the Skeletal Muscle?.- Session III Receptor-Receptor Interactions in Psychoactive Drug Action.- A Anxiolytic Drugs.- 29. Multiple Signal in GABAergic Transmission: A New Family of Modulatory Peptides.- B Antidepressant Drugs.- 30. Different Presynaptic Receptors Modulate Neuronal Uptake and Transmitter Release in Serotoninergic Nerve Terminals.- 31. Serotonin/Norepinephrine Receptor Interactions: Sensitivity Changes after Antidepressants and Lesions.- 32. Receptor Interactions in Antidepressant Neurochemical Mechanisms: Modulation by Membrane Components.- 33. Interactions of Coexisting Neurotransmitters and Effects of Chronic Drug Treatment.- 34. Are Opiates Involved in the Adaptation Processes of Dopamine Receptors that Follow Chronic Drug Exposure?.- 35. GABA Receptors, Depression and Antidepressant Drug Action.- Session IV Effects of Intracellular Messengers on the Membrane Receptors.- 36. Receptor¿Receptor Interactions Mediated by Protein Phosphorylation.- 37. The Molecular Logic of Presynaptic Facilitation and Inhibition.- 38. Control of Plasma Membrane Transducing Systems by Second Messengers and by Cellular Metabolism.- Session V Physiological and Pharmacological Studies on Interactions between Receptors in Synaptic Membranes.- A Neurophysiological Studies.- 39. The Relationships of Receptors for Phencyclidine and Sigma Opiates in Rat Cerebellum: An Electrophysiological Analysis.- 40. Modulation of Synaptic Potentials in situ by Specific Agonists of Excitatory Amino Acids.- B Behavioural and Cardiovascular Studies.- 41. On the Role of Receptor¿Receptor Interactions in Central Cardiovascular Regulation: Functional Studies on the Interactions between ?2-adrenergic and Neuropeptide Y Receptors in the Rat Medulla Oblongata.- 42. Behavioral Analysis of the Functional Significance of Peptide-Transmitter Coexistences.- Overview.- 43. Receptor Regulation and Receptor-Receptor Communication.