论文部分内容阅读
Clinical application of transcranial direct current stimulation provides non-invasive approaches for the treatment of drug-resistant seizures.Previous studies showed that field stimulation could modulate synaptic plasticity as well as influence epileptiform activities in various brain regions, such as in motor cortex and hippocampus.However, seldom research focues the field effect on synaptic transmission within thalamocortical system, the important circuitry in sensory processing and in generating epileptiform activities.The present study is aimed to investigate the effect of DC field stimulation on the changes of thalamocingulate synaptic plasticity and seizure-like activities generated within this circuitry.Previously developed brain slice cutting method preserve the pathway between medial thalamus (MT) and anterior cingulate cortex (ACC) was used to address the question.Application of 10 minutes of anodal DC field stimulation could potentiate the synaptic transmission in MT-ACC pathway.The potentiation effect could last 20 minutes after ceasing application of DC stimulation.The potentiation effect was mediated by the volume changes of extracellular space, which will in turn increase the concentration of neurotransmitter.Using furosemide to stabilize the extracellular volume or APV to antagonize the effect of increasing concentration of neurotransmitter could prevent the potentiation.Drug resistant seizure was induced by perfusion brain slice with 4-amino pyridine and bicuculline.Application of anodal DC enhanced the seizure-like activities while cathodal DC suppressed them.Furosemide also abolished the effect of DC field on seizure-like activities.Thus it indicated that DC field also influenced the seizurelike activities by the modulation of extracellular space.