title: Effect of tryptophan on the behavior of nonstressed and stressed mice in Porsolt's swim test.
abstract: The effect of tryptophan on immobility in Porsolt's swim test was studied in male NIH Swiss mice. Preexposure to a swim or fight-stressor was included in the design. Doses of tryptophan (0, 12.5, 50, 75, 100, 125 and 200 mg/kg) were administered intraperitoneally 60 min prior to the swim test. In the nonstressed mice tryptophan had an U-shaped dose-response relationship: immobility in the water was dose-dependently shortened after doses from 0 to 100 mg/kg, whereas after 125 and 200 mg/kg tryptophan the immobility times did not differ from the values obtained after a saline injection. Preexposure to a swim- or fight-stressor did not make mice more sensitive to the effects of tryptophan. Tryptophan (0-300 mg/kg) had no effect on exploratory behavior or locomotor activity in the holeboard, suggesting that sedation was not a factor in the swim test results. The findings suggest that tryptophan has antidepressant -like properties in Porsolt's swim test.
authors.affiliation: Laboratory of Clinical Studies, DICBR, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD 20892.
authors.forename: L A
authors.initials: LA
authors.lastname: Hilakivi-Clarke
authors.forename: M J
authors.initials: MJ
authors.lastname: Durcan
authors.forename: R G
authors.initials: RG
authors.lastname: Lister
authors.forename: M
authors.initials: M
authors.lastname: Linnoila
mesh_terms: D000818:Animals; D000928:Antidepressive Agents; D004195:Disease Models, Animal; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D011581:Psychological Tests / Q000379:methods; D013315:Stress, Psychological / Q000188:drug therapy*; D013550:Swimming; D014364:Tryptophan / Q000494:pharmacology*
chemical_list: D000928:Antidepressive Agents; D014364:Tryptophan