Contribution of the dopaminergic system to the effect of chronic fluoxetine in the rat forced swim test
AUTOR(ES)
León, Laura A., Cardenas, Fernando P.
FONTE
Psychology & Neuroscience
DATA DE PUBLICAÇÃO
2008-06
RESUMO
Chronic administration of selective serotonin reuptake inhibitors (SSRI) enhances dopaminergic activity. However, the role of enhanced dopaminergic transmission in the therapeutic effects of this kind of antidepressants is still unclear. Drugs producing dopaminergic activation lead to an increment in general activity. Thus, it is reasonable to assume that some of the therapeutic effects of SSRIs are due to dopaminergic enhanced functionality. The forced swim test (FST) is a widely used test in the screening of new compounds with potential antidepressant activity. In this study the effects of pretreatment with low doses of the DA release inductor cocaine and the D2, D3 and D4 antagonist haloperidol were analyzed in the FST on rats submitted to chronic intragastric administration of the SSRI fluoxetine. Our results show that animals treated with fluoxetine and pre-treated with cocaine had significantly higher latencies than saline or haloperidol pre-treated subjects. Among both fluoxetine and saline treated animals, those pre-treated with cocaine had significant lesser immobility time. Haloperidol pre-treated animals had significantly higher immobility time than those pre-treated with saline. From these results, it is clear that the pharmacological modification of dopaminergic systems leads to behavioral changes in rats treated with both saline and fluoxetine. The FST does not have enough precision as to distinguish between dopaminergic and nondopaminergic components in the antidepressant effects of SSRIs, for this reason the use of the FST in combination to other models is mandatory.
Documentos Relacionados
- Influence of gender and estrous cycle in the forced swim test in rats
- Estrogen alters behavior and forebrain c-fos expression in ovariectomized rats subjected to the forced swim test
- Antidepressant- and anxiogenic-like effects of acute 5-HT2C receptor activation in rats exposed to the forced swim test and elevated plus maze
- Antidepressant-like effect of Hoodia gordonii in a forced swimming test in mice: evidence for involvement of the monoaminergic system
- Effect of forced expirations on mucus clearance in patients with chronic airflow obstruction: effect of lung recoil pressure.