title: Acute exposure to morphine suppresses cytotoxic T-lymphocyte activity.
abstract: Chronic exposure (11 days) to morphine has previously been shown to suppress splenic and peritoneal cytotoxic T-lymphocyte activity through mu-opioid receptors. The present study was undertaken to assess the effects of varying the frequency of exposure to morphine on cytotoxic T-lymphocyte activity in C3H/HeN mice immunized with C57BL/6 splenocytes. Mice subchronically treated with morphine (50.0 mg/kg) showed no measurable suppression of splenic natural killer activity or splenic or peritoneal cytotoxic T-lymphocyte activity. However, mice treated acutely with 50.0 mg/kg of morphine exhibited a significant suppression of peritoneal but not splenic cytotoxic T-lymphocyte activity. Naltrexone pretreatment of mice receiving an acute dose of morphine blocked the suppression, implicating the involvement of opioid receptors. Using column depletion chromatography, peritoneal exudate cells mediating cytotoxic T-lymphocyte activity were both CD4+CD8- and CD4-CD8+. Collectively, the results suggest that the duration of opioid (morphine) exposure differentially affects peritoneal cytotoxic T-lymphocyte activity. These results may have important implications regarding immunity to viral infections in individuals who abuse drugs such as heroin.
authors.affiliation: Department of Microbiology, LSU Medical Center, New Orleans 70112-1393, USA.
authors.forename: G W
authors.initials: GW
authors.lastname: Carpenter
authors.forename: L
authors.initials: L
authors.lastname: Breeden
authors.forename: D J
authors.initials: DJ
authors.lastname: Carr
mesh_terms: D000818:Animals; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D007519:Isoantigens / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009020:Morphine / Q000633:toxicity*; D010529:Peritoneal Cavity / Q000166:cytology; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects*; D014407:Tumor Cells, Cultured
chemical_list: D007519:Isoantigens; D009020:Morphine