In the XXXX forced swimming test, chronic but not subacute administration of dual @entity750 /NA antidepressant treatments may produce greater effects than selective drugs.

@entity308 @entity1338 @entity905 @entity5829 @entity13332 @entity1153 @entity750 @entity35 @entity1063
The @entity35 forced swimming test (FST) distinguishes selective @entity750 ( @entity750 ) and selective @entity1063 (NA) reuptake-inhibitors, which respectively increase swimming and climbing behaviours. However, NA-system-mediated inhibition of @entity750 -induced swimming prevents dual @entity750 /NA reuptake-inhibition to produce concurrently climbing with swimming. Since adaptative neurochemical processes occur in the treatment of @entity308 , we examined the influence of long-term antidepressant treatment on these interactions. METHODS: (1) Selective [ @entity905 : 10 mg/kg; @entity5829 : 10 mg/kg] and non-selective [ @entity1153 : 40 mg/kg; @entity13332 : 20 mg/kg] antidepressants were administered subacutely (3inj) and chronically (17inj) over 16 days. (2) A subacute @entity905 - @entity5829 combination (10-10 mg/kg) was administered in @entity35 that were pre-treated with chronic- @entity5829 (10 mg/kg per day, 14 days). (3) NA-system-mediated interactions were further examined by combining the alpha(2)-receptor agonist @entity1338 (5, 10, 20, 200 microg/kg) with 10 mg/kg @entity905 . RESULTS: (1) Long-term treatment with either @entity905 or @entity5829 does not modify the behavioural response produced by their subacute administration. (2) In contrast, whereas subacute-milnacipran increases climbing solely, chronic-milnacipran produces greater anti-immobility effects and increases both climbing and swimming behaviours. Similarly, the @entity905 - @entity5829 combination produces climbing solely, but increases both climbing and swimming behaviours in animals pre-treated with chronic- @entity5829 . Chronic but not subacute- @entity13332 increases swimming behaviour. (3) @entity1338 dose-dependently antagonizes @entity905 -induced anti-immobility effects and swimming behaviour. CONCLUSIONS: Chronic enhancement of NA-transmission alters NA-system-mediated inhibition of @entity750 -induced behaviour in the FST, which may involve alpha(2)-receptors.
