Brooks-Kayal Amy R
Children's Hospital of Philadelphia, University of Pennsylvania, Abramson Research Center, Philadelphia, Pennsylvania 19104-4318, USA.
Epilepsia. 2005;46 Suppl 7:29-38. doi: 10.1111/j.1528-1167.2005.00301.x.
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.
未成熟的大脑极易发生癫痫发作。癫痫易感性的增加似乎至少部分是由于发育变化,这种变化打破了大脑中兴奋性和抑制性神经递质系统之间的平衡,使大脑偏向于兴奋状态。多种因素,包括γ-氨基丁酸能和谷氨酸能受体组成、数量和分布的变化,都促成了出生后早期出现的典型边缘系统过度兴奋。经历长时间或重复性癫痫发作的婴幼儿随后患癫痫的风险会增加。迄今为止的证据表明,癫痫持续状态会导致边缘环路的分子和细胞结构发生永久性变化,进而导致海马体兴奋性长期增加,并在以后的生活中降低癫痫发作阈值。