Synchrotron X-ray interlaced microbeams suppress paroxysmal oscillations in neuronal networks initiating generalized epilepsy.

摘要: Radiotherapy has shown some efficacy for epilepsies but the insufficient confinement of radiation dose to pathological target reduces its indications. Synchrotron-generated X-rays overcome this limitation and allow delivery focalized doses discrete brain volumes via interlaced arrays microbeams (IntMRT). Here, we used IntMRT structures involved in seizure generation a rat model absence epilepsy (GAERS). We addressed issue whether how synchrotron radiotherapeutic treatment suppresses epileptic activities neuronal networks. was somatosensory cortex (S1Cx), region GAERS. The antiepileptic mechanisms were investigated by recording multisite local-field potentials intracellular activity irradiated S1Cx pyramidal neurons vivo. MRI histopathological images displayed precise sharp deposition revealed no impairment surrounding tissues. Local-field from behaving animals demonstrated quasi-total abolition epileptiform within target. unable initiate seizures, whereas neighboring non-irradiated cortical thalamic regions could still produce oscillations. In vivo recordings showed that strongly hyperpolarized decreased excitability reduction spontaneous synaptic activities. These functional alterations explain suppression large-scale synchronization Our work provides first post-irradiation electrophysiological individual neurons. Altogether, our data are critical step towards understanding X-ray impacts physiology epileptogenic processes.