Combined neuromodulatory interventions in acute experimental pain : assessment of melatonin and non-invasive brain stimulation

Transcranial direct current stimulation (tDCS) and melatonin can effectively treat pain. Given their potentially complementary mechanisms of action, their combination could have a synergistic effect. Thus, we tested the hypothesis that compared to the control condition and melatonin alone, tDCS comb...

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Detalles Bibliográficos
Autores: Silva, Nadia Regina Jardim da, Laste, Gabriela, Deitos, Alícia, Stefani, Luciana Paula Cadore, Canto, Gustavo Cambraia do, Torres, Iraci Lucena da Silva, Brunoni, Andre Russowsky, Fregni, Felipe, Caumo, Wolnei
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Brasil
Institución:Universidade Federal do Rio Grande do Sul (UFRGS)
Repositorio:Repositório Institucional da UFRGS
Idioma:inglés
OAI Identifier:oai:www.lume.ufrgs.br:10183/187803
Acceso en línea:http://hdl.handle.net/10183/187803
Access Level:acceso abierto
Palabra clave:Estimulação magnética transcraniana
Limiar da dor
Melatonina
Ensaio clínico
tDCS
TMS
CPM
Pain threshold
Melatonin
Clinical trial
Descripción
Sumario:Transcranial direct current stimulation (tDCS) and melatonin can effectively treat pain. Given their potentially complementary mechanisms of action, their combination could have a synergistic effect. Thus, we tested the hypothesis that compared to the control condition and melatonin alone, tDCS combined with melatonin would have a greater effect on pain modulatory effect, as assessed by quantitative sensory testing (QST) and by the pain level during the Conditioned Pain Modulation (CPM)-task. Furthermore, the combined treatment would have a greater cortical excitability effect as indicated by the transcranial magnetic stimulation (TMS) and on the serum BDNF level. Healthy males (n = 20), (aged 18–40 years), in a blinded, placebo-controlled, crossover, clinical trial, were randomized into three groups: sublingual melatonin (0.25 mg/kg) + a-tDCS, melatonin (0.25 mg/kg) + sham-(s)-tDCS, or sublingual placebo+sham-(s)- tDCS. Anodal stimulation (2 mA, 20 min) was applied over the primary motor cortex. There was a significant difference in the heat pain threshold ( C) for melatonin+a-tDCS vs. placebo+s-tDCS (mean difference: 4.86, 95% confidence interval [CI]: 0.9 to 8.63) and melatonin+s-tDCS vs. placebo+s-tDCS (mean: 5.16, 95% CI: 0.84 to 8.36). There was no difference between melatonin+s-tDCS and melatonin+a-tDCS (mean difference: 0.29, 95% CI: 3.72 to 4.23). The mean change from the baseline on amplitude of motor evocate potential (MEP) was significantly higher in the melatonin+a-tDCS (19.96% 5.2) compared with melatonin+s-tDCS group (1.36% 5.35) and with placebo+s-tDCS group (3.61% 10.48), respectively (p < 0.05 for both comparisons). While melatonin alone or combined with a-tDCS did not significantly affect CPM task result, and serum BDNF level. The melatonin effectively reduced pain; however, its association with a-tDCS did not present an additional modulatory effect on acute induced pain.