Effects of ethanol on fight- or swim-stressed mice in Porsolt's swim test.
The effects of ethanol in Porsolt's swim test on mice preexposed to fight- or swim-stressors were investigated. The control mice did not change their behavior in the swim test after an acute injection of 0.4 or 0.8 g/kg ethanol; 1.2 g/kg ethanol increased their immobility in one but not in another experiment. The mice exposed to continuous fight-attacks in their home cage by one dominant mouse shortened immobility after 0.8 g/kg ethanol as well as tended to shorten it after 0.4 g/kg ethanol. The mice that were forced to swim in the water twice before the actual swim test responded to 0.4 g/kg ethanol by shortening immobility; 0.8 g/kg tended to have the same effect; 1.2 g/kg ethanol just failed to lengthen immobility of the fight-stressed mice and had no effect on the swim-stressed mice. Because antidepressant drugs decrease and stressors increase immobility in the swim test, the test may serve as a putative animal model of depression. The present findings showed that low doses of ethanol reverse lengthened immobility of mice preexposed to a stressor. This suggests that ethanol either has antidepressant-like properties, or it improves animal's ability to cope with a stressful situation, or both.
Hilakivi
L A
LA
Laboratory of Clinical Studies, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892.
Durcan
M J
MJ
Lister
R G
RG
D000374:Aggression; D000818:Animals; D003891:Desipramine / Q000494:pharmacology; D000431:Ethanol / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009043:Motor Activity / Q000187:drug effects*; D012016:Reference Values; D012149:Restraint, Physical; D013315:Stress, Psychological; D013550:Swimming
D000431:Ethanol; D003891:Desipramine