Rearranging Receptors

The immature brain is highly susceptible to seizures. The heightened susceptibility to seizures appears to be due, at least in part, to developmental changes that skew the balance between excitatory and inhibitory neurotransmitter systems in the brain in favor of a state of excitation. Multiple factors, including changes in GABAergic and glutaminergic receptor composition, number, and distribution, all contribute to produce the characteristic limbic hyperexcitability seen during the early postnatal period. Infants and young children who experience prolonged or repetitive seizures have an increased risk of subsequently developing epilepsy. Evidence to date suggests that status epilepticus produces permanent changes in the molecular and cellular structure of limbic circuitry that, in turn, result in a long-lasting increase in hippocampal excitability and lower seizure thresholds in later life.