Brief seizure episodes induce long-term potentiation and mossy fibre sprouting in the hippocampus

Abstract

Much of our present understanding of the cellular mechanisms of learning and memory derives from studies on the hippocampus in which long-term potentiation (LTP) of synaptic transmission is produced by a train of high-frequency electrical stimulation or by potassium channel blockers. The hippocampus is also a seizure-prone region and recent studies have revealed that brief seizure episodes produce remarkably long-lasting changes which are reminiscent of 'classical' LTP. A brief seizure episode also sets in motion a cascade of events that includes changes in gene expression, sprouting of fibres and the establishment of new synaptic contacts. This paper reviews this use-dependent structural rearrangement of the neuronal network and discusses its possible role in epilepsy and as a model of plasticity in the adult nervous system.