Effects of a single administration of morphine or footshock stress on natural killer cell cytotoxicity.
We previously reported that daily exposure for 4 days to an inescapable form of footshock stress, known to cause opioid-mediated analgesia, suppressed the cytotoxic activity of splenic natural killer (NK) cells in rats. Similarly, daily injection of high doses of morphine (greater than or equal to 30 mg/kg) for 4 days also suppressed splenic NK cell activity. We now report that a single exposure to the opioid form of footshock stress or a single high dose of morphine induces suppression of splenic NK cell cytotoxicity. This effect is evident 3 h after treatment, returning to normal by 24 h. Morphine-induced NK suppression is evident in both male and female rats, is blocked by the opiate antagonist naltrexone, and develops tolerance. Morphine-induced NK suppression is seen in cells derived simultaneously from the spleen, bone marrow, and peripheral blood, suggesting that this suppression does not result from a selective egress of NK cells from the spleen.
Shavit
Y
Y
Department of Psychology, University of California, Los Angeles 90024-1563.
Martin
F C
FC
Yirmiya
R
R
Ben-Eliyahu
S
S
Terman
G W
GW
Weiner
H
H
Gale
R P
RP
Liebeskind
J C
JC
D000818:Animals; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D004597:Electroshock; D005260:Female; D007165:Immunosuppression Therapy; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D009020:Morphine / Q000494:pharmacology*; D009271:Naltrexone / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D013312:Stress, Physiological / Q000276:immunology*
D009271:Naltrexone; D009020:Morphine