Pathological high frequency oscillations associate with increased GABA synaptic activity in pediatric epilepsy surgery patients.

Pathological high frequency oscillations associate with increased GABA synaptic activity in pediatric epilepsy surgery patients. Neurobiol Dis. 2019 Oct 17;:104618 Authors: Cepeda C, Levinson S, Nariai H, Yazon VW, Tran C, Barry J, Oikonomou KD, Vinters HV, Fallah A, Mathern GW, Wu JY Abstract Pathological high-frequency oscillations (HFOs), specifically fast ripples (FRs, >250 Hz), are pathognomonic of an active epileptogenic zone. However, the origin of FRs remains unknown. Here we explored the correlation between FRs recorded with intraoperative pre-resection electrocorticography (ECoG) and spontaneous synaptic activity recorded ex vivo from cortical tissue samples resected for the treatment of pharmacoresistant epilepsy. The cohort included 47 children (ages 0.22-9.99 yr) with focal cortical dysplasias (CD types I and II), tuberous sclerosis complex (TSC) and non-CD pathologies. Whole-cell patch clamp recordings were obtained from pyramidal neurons and interneurons in cortical regions that were positive or negative for pathological HFOs, defined as FR band oscillations (250-500 Hz) at ECoG. The frequency of spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and IPSCs, respectively) was compared between HFO+ and HFO- regions. Regardless of pathological substrate, regions positive for FRs displayed significantly increased frequencies of sIPSCs compared with regions negative for FRs. In contrast, the freque...
Source: Neurobiology of Disease - Category: Neurology Authors: Tags: Neurobiol Dis Source Type: research