Synchronization of GABAergic interneuronal networks during seizure-like activity in the rat horizontal hippocampal slice.

摘要: We studied the contribution of GABAergic (gamma-aminobutyric acid) neurotransmission to epileptiform activity using horizontal hippocampal rat brain slice. Seizure-like (ictal) was evoked in CA1 area by applying high-frequency trains (80 Hz for 2 s) Schaffer collaterals. Whole-cell recordings from stratum oriens-alveus interneurons revealed burst firing with superimposed spiking which synchronous field events and pyramidal cell during ictal activity. On other hand, interictal interneuronal bursts were large-amplitude inhibitory postsynaptic potentials (IPSPs) cells. Excitatory simultaneously received neurons afterdischarge, bursting potential events. The GABAA receptor antagonist bicuculline greatly reduced duration layer, rhythmic With intact transmission, large amplitude IPSPs (9.8 +/- 2.4 mV) cells, bursting. Simultaneous dual widely separated periods, indicative widespread synchrony throughout hippocampus. CA3 fired recorded glutamate antagonists abolished These observations provide evidence that network may be entrained hyperexcitable states glutamatergic mechanisms.