Valproate decreases frequency facilitation at mossy fiber--CA3 synapses after status epilepticus.

Mossy fiber to CA3 synapses exhibit metaplasticity during the development of epilepsy, and valproate in control animals can modulate long-term plasticity at this synapse. Here we show that valproate alters frequency facilitation (short-term plasticity) at this synapse in hippocampal slices from post-status epilepticus but not control animals. This indicates that valproate can have specific actions in the "epileptic" brain.