Immunosuppression induced by a conditioned stimulus associated with cocaine self-administration.
Cocaine addiction is known to impair immune system function, but the effects of repeated treatment with cocaine in a self-administration model, its withdrawal as well as reinstatement of cocaine-seeking behavior on cell-mediated immunity are not well known. Cocaine self-administered for 18 days induced a significant increase in spleen weight, plasma corticosterone levels, interleukin (IL)-10, and tumor necrosis factor-alpha production, while concanavalin A-stimulated proliferation responses of peripheral blood T-lymphocytes and interferon-gamma production by splenic lymphocytes were not altered. After 10 days withdrawal from cocaine, reinstatement of cocaine seeking behavior induced either by a priming dose of the drug (unconditioned stimulus), by cue previously associated with cocaine self-administration (conditioned stimuli), or by both these stimuli evoked similar changes in several immunological parameters, for example, a decrease in relative spleen weight, proliferative activity of splenocytes, and their ability to produce IL-10. The results showed that the cue previously associated with cocaine suppressed some parameters of cell-mediated immunity to the same degree as re-exposure to cocaine. The present study provides the first evidence that alterations of immune status can be conditioned by environmental stimuli paired with cocaine administration.
Kubera
Marta
M
Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland. kubera@if-pan.krakow.pl
Filip
Małgorzata
M
Budziszewska
Bogusława
B
Basta-Kaim
Agnieszka
A
Wydra
Karolina
K
Leskiewicz
Monika
M
Regulska
Magdalena
M
Jaworska-Feil
Lucylla
L
Przegalinski
Edmund
E
Machowska
Anna
A
Lason
Władysław
W
D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D003042:Cocaine / Q000008:administration & dosage / Q000009:adverse effects*; D019970:Cocaine-Related Disorders; D003216:Conditioning, Operant / Q000187:drug effects; D003345:Corticosterone / Q000097:blood; D005108:Extinction, Psychological / Q000187:drug effects; D007108:Immune Tolerance / Q000187:drug effects*; D007111:Immunity, Cellular / Q000187:drug effects*; D016753:Interleukin-10 / Q000378:metabolism; D008297:Male; D009929:Organ Size; D051381:Rats; D017208:Rats, Wistar; D012646:Self Administration; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013375:Substance Withdrawal Syndrome; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects / Q000378:metabolism
D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D003042:Cocaine; D003345:Corticosterone