The effects of long-term dopaminergic treatment on locomotor behavior in rats

Autor(es)

Oliveira de Almeida, Welinton Alessandro ; Esteves, Andrea Maculano ; de Almeida-junior, Canuto Leite ; Lee, Kil Sun ; Frank, Miriam Kannebley ; Mariano, Melise Oliveira ; Frussa-Filho, Roberto ; Tufik, Sergio ; de Mello, Marco Tulio

• Tipo de documento: Artigo Científico
• Fonte: SLEEP SCIENCE; v. 7, n. 4, p. 6-pg., 2014-12-01.

Resumo

Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole-PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions. (C) 2014 Brazilian Association of Sleep. Production and Hosting by Elsevier B.V. (AU)

• Processo FAPESP: 98/14303-3 - Center for Sleep Studies
• Beneficiário: Sergio Tufik
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 11/12540-4 - Modelo animal de augmentation relacionado aos distúrbios do movimento do sono
• Beneficiário: Welinton Alessandro Oliveira de Almeida
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica