Proinflammatory cytokines differentially affect leverpress avoidance acquisition in rats.
Recent evidence indicates that the pro-inflammatory cytokines (PICs) can affect learning and memory processes. To examine the effect of the PICs on leverpress escape/avoidance conditioning, we injected male Sprague-Dawley rats with IL-1beta, IL-6 (both 3.0 microg/kg, i.p.), TNFalpha (6.0 microg/kg, i.p.) or vehicle, 24h before a single 4-h session of leverpress escape/avoidance conditioning. The TNFalpha-treated animals made more avoidance responses and fewer escape responses than controls during the last hour of the session. Further, both TNFalpha- and IL-1beta-treated animals had a higher percent avoidance than controls during the 4th hour of the session. None of the cytokines had an effect on the number of leverpresses during safety, a putative measure of anxiety. Results are discussed in terms of the differential central effects of the pro-inflammatory cytokines and the possible relationship to avoidance conditioning.
Brennan
Francis X
FX
Medical Research Service (151), Philadelphia VA Medical Center, 3900 Woodland Ave., Philadelphia, PA 19104, USA. francis.brennan@med.va.gov
Beck
Kevin D
KD
Servatius
Richard J
RJ
D000818:Animals; D001143:Arousal / Q000187:drug effects*; D001245:Association Learning / Q000187:drug effects; D001362:Avoidance Learning / Q000187:drug effects*; D001921:Brain / Q000187:drug effects; D003214:Conditioning, Classical / Q000187:drug effects*; D004597:Electroshock; D004924:Escape Reaction / Q000187:drug effects*; D007375:Interleukin-1 / Q000494:pharmacology*; D015850:Interleukin-6 / Q000494:pharmacology*; D008297:Male; D011597:Psychomotor Performance / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects; D011994:Recombinant Proteins / Q000494:pharmacology; D012153:Retention, Psychology / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D007375:Interleukin-1; D015850:Interleukin-6; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha