31 August 2009
Revisiting tolerance from the endogenous morphine perspective
George B. Stefano, Richard M. Kream, Tobias EschMed Sci Monit 2009; 15(9): RA189-198 :: ID: 878168
Abstract
Tolerance represents a dynamic mechanism that can be used to temper various regulatory processes regardless of whether they mediate excitation or inhibition. Tolerance operationally directs state-dependent attenuation of the action of endogenous and exogenous morphine. For example, tolerance ensures that immuno-inhibition induced by morphine does not compromise a requisite functional system over an extended period of time. In the nervous system, tolerance to inhibitory action insures that excitatory tone is resumed. Thus, desensitization sets in and allows various essential processes to be operational once again. Clearly, the temporal rebound of diverse immune and nervous processes involved with opiate actions provides a self-contained operational mechanism to ensure survival of the organism. Furthermore, love and/or pleasure, and satiety, are complex neurobiological phenomena linked to limbic brain reward circuitry. These processes are critically dependent on oxytocin, vasopressin, dopamine, endogenous morphine and serotoninergic signaling. Naturally rewarding and/or pleasurable activities are usually governed by beneficial biological behaviors like eating, sex, and reproduction. It is our contention that critically important tolerance mechanisms extend to behaviors mediated by CNS reward systems. In other words, we become satisfied with sex, food, pleasure for the moment and disinterest creeps in until the "urges" return.
Keywords: Reward, Receptors, Opioid - metabolism, Narcotics - pharmacology, Protein Isoforms - metabolism, Morphine Dependence, Love, Morphine - pharmacology, Immune System - metabolism, Drug Tolerance, Brain - drug effects, Signal Transduction - physiology
Editorial
01 May 2024 : Editorial
Editorial: First Regulatory Approval for Adoptive Cell Therapy with Autologous Tumor-Infiltrating Lymphocytes (TILs) – Lifileucel (Amtagvi)DOI: 10.12659/MSM.944927
Med Sci Monit 2024; 30:e944927
In Press
12 Mar 2024 : Clinical Research
Preoperative Blood Transfusion Requirements for Hemorrhoidal Severe Anemia: A Retrospective Study of 128 Pa...Med Sci Monit In Press; DOI: 10.12659/MSM.943126
12 Mar 2024 : Clinical Research
Tissue Inhibitors of Metalloproteinase 1 (TIMP-1) and 3 (TIMP-3) as New Markers of Acute Kidney Injury Afte...Med Sci Monit In Press; DOI: 10.12659/MSM.943500
12 Mar 2024 : Review article
Optimizing Behçet Uveitis Management: A Review of Personalized Immunosuppressive StrategiesMed Sci Monit In Press; DOI: 10.12659/MSM.943240
12 Mar 2024 : Clinical Research
Metabolomic Alterations in Methotrexate Treatment of Moderate-to-Severe PsoriasisMed Sci Monit In Press; DOI: 10.12659/MSM.943360
Most Viewed Current Articles
17 Jan 2024 : Review article
Vaccination Guidelines for Pregnant Women: Addressing COVID-19 and the Omicron VariantDOI :10.12659/MSM.942799
Med Sci Monit 2024; 30:e942799
14 Dec 2022 : Clinical Research
Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase LevelsDOI :10.12659/MSM.937990
Med Sci Monit 2022; 28:e937990
16 May 2023 : Clinical Research
Electrophysiological Testing for an Auditory Processing Disorder and Reading Performance in 54 School Stude...DOI :10.12659/MSM.940387
Med Sci Monit 2023; 29:e940387
01 Jan 2022 : Editorial
Editorial: Current Status of Oral Antiviral Drug Treatments for SARS-CoV-2 Infection in Non-Hospitalized Pa...DOI :10.12659/MSM.935952
Med Sci Monit 2022; 28:e935952