Effects of Anterior Thalamic Nucleus Deep Brain Stimulation in Chronic Epileptic Rats

Autor(es):Mostrar menos -

Covolan, Luciene ^[1] ; de Almeida, Antonio-Carlos G. ^[2] ; Amorim, Beatriz ^[1] ; Cavarsan, Clarissa ^[1] ; Miranda, Maisa Ferreira ^[2] ; Aarao, Mayra C. ^[2] ; Madureira, Ana Paula ^[2] ; Rodrigues, Antonio M. ^[2] ; Nobrega, Jose N. ^[3] ; Mello, Luiz E. ^[1] ; Hamani, Clement ^{[1, 3, 4]}

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Disciplina Neurofisiol, Sao Paulo - Brazil

^[2] Univ Fed Sao Joao del Rei, Lab Neurociencia Expt & Computac, Sao Joao Del Rei - Brazil

^[3] Ctr Addict & Mental Hlth, Behav Neurobiol Lab, Toronto, ON - Canada

^[4] Univ Toronto, Toronto Western Hosp, Div Neurosurg, Toronto, ON M5T 2S8 - Canada

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 9, n. 6 JUN 3 2014.
• Citações Web of Science: 18

Resumo

Deep brain stimulation (DBS) has been investigated for the treatment of epilepsy. In rodents, an increase in the latency for the development of seizures and status epilepticus (SE) has been reported in different animal models but the consequences of delivering stimulation to chronic epileptic animals have not been extensively addressed. We study the effects of anterior thalamic nucleus (AN) stimulation at different current intensities in rats rendered epileptic following pilocarpine (Pilo) administration. Four months after Pilo-induced SE, chronic epileptic rats were bilaterally implanted with AN electrodes or had sham-surgery. Stimulation was delivered for 6 h/day, 5 days/week at 130 Hz, 90 mu sec. and either 100 mu A or 500 mu A. The frequency of spontaneous recurrent seizures in animals receiving stimulation was compared to that recorded in the preoperative period and in rats given sham treatment. To investigate the effects of DBS on hippocampal excitability, brain slices from animals receiving AN DBS or sham surgery were studied with electrophysiology. We found that rats treated with AN DBS at 100 mu A had a 52% non-significant reduction in the frequency of seizures as compared to sham-treated controls and 61% less seizures than at baseline. Animals given DBS at 500 mu A had 5.1 times more seizures than controls and a 2.8 fold increase in seizure rate as compared to preoperative values. In non-stimulated controls, the average frequency of seizures before and after surgery remained unaltered. In vitro recordings have shown that slices from animals previously given DBS at 100 mu A had a longer latency for the development of epileptiform activity, shorter and smaller DC shifts, and a smaller spike amplitude compared to non-stimulated controls. In contrast, a higher spike amplitude was recorded in slices from animals given AN DBS at 500 mu A. (AU)

• Processo FAPESP: 12/50950-2 - Avaliação celular dos efeitos estimulação cerebral profunda no núcleo anterior do tálamo em modelos experimentais de epilepsia do lobo temporal
• Beneficiário: Luciene Covolan
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/50680-2 - Investigação multimodal da epileptogênese com ênfase na incorporação de novos modelos e novas ferramentas
• Beneficiário: Iscia Teresinha Lopes Cendes
• Linha de fomento: Auxílio à Pesquisa - Temático