1. Introduction: The Brain-Immune Axis: Role of Opiates and Other Substances of Abuse, the Hypothalmic-Pituitary-Adrenal Axis and Behavior.- 2. Detection of ?-Opioid Receptor mRNA in Immature T Cells.- 3. Identification of Opioid Receptors in the Immune System Using a Novel Combination of Selective Opioid Ligands and Indirect Phycoerythrin Immunofluorescence.- 4. Kappa Opioid Receptors on Three Related Thymoma Cell Lines: Differences in Receptor-Effector Coupling.- 5. Delta Opioid Agonists Inhibit Proliferation of Highly Purified Murine CD4+ and CD8+ T-Cells.- 6. Mitogenic Activation of Human T Lymphocytes Induces a High Affinity Morphine Binding Site.- 7. Morphine-Induced Suppression of Thymocyte Proliferation Is Mediated by Inhibition of I1-2 Synthesis.- 8. Active ?-Endorphin Metabolites Generated by T-Cell Ectopeptidases.- 9. The Cellular Basis for Opioid-Induced Immunosuppression.- 10. Endogenous Opioid Peptides Suppress Cytokine-Mediated Upregulation of HIV-1 Expression in the Chronically Infected Promonocyte Clone U1.- 11. Relevance of Opioid Bimodality to Tolerance/Dependence Formation: From Transmitter Release to Second Messenger Formation.- 12. Agonist Induced Constitutive Receptor Activation As a Novel Regulatory Mechanism: ? Receptor Regulation.- 13. Expression of Cannabinoid Receptor mRNA in Murine and Human Leukocytes.- 14. Cannabinoid Stimulation of Arachidonate Metabolism in Human Peripheral Blood Mononuclear Leukocytes.- 15. Marijuana, Receptors and Immunomodulation.- 16. Mouse Strain Differences in in vivo and in vitro Immunosuppressive Effects of Opioids.- 17. The Clastogenicity of Morphine Sulfate in vivo.- 18. Cellular Mechanisms Involved in Morphine-Mediated Suppression of CTL Activity.- 19. Evidence for the Involvement of Macrophage-Derived Nitric Oxide in the Immunomodulatory Effect of Morphine and Aversive Pavlovian Conditioning.- 20. Mechanisms Whereby Macrophage-Derived Nitric Oxide Is Involved in the Immunomodulatory Effects of Morphine.- 21. Effects of Central Administration of Morphine on Immune Status in Lewis and Wistar Rats.- 22. Morphine Alteration of Histamine Release in vivo.- 23. Effect of Chronic Morphine Treatment on Immune Responses to Keyhole Limpet Hemocyanin in Swine.- 24. SIV Mutations Detected in Morphine-Treated Macaca mulatta Following SIVmac239 Infection.- 25. Adjuvant Effects on Morphine-Induced Suppression of Immune Responses to MN rgp120/HIV-1 in Mice.- 26. Possible Mechanisms of Immunotoxicity Following in vivo Exposure to the Inhalant, Isobutyl Nitrite.- 27. Role of Immune Processes in Peripheral Opioid Analgesia.- 28. Chronic Treatment with Morphine and Ethanol, but Not Cocaine, Attenuates I1-1? Activation of FOS Expression in the Rat Hypothalamic Paraventricular Nucleus.- 29. Effects of r-Hu-Interferon-?2A in the Brain.- 30. Quantification of Macrophage-Derived Substance P Receptor mRNA Using Competitive Polymerase Chain Reaction.- 31. HIV-1 Heterogeneity and Cytokines: Neuropathogenesis.