Kuruba Ramkumar, Hattiangady Bharathi, Shetty Ashok K
Department of SurgeryDuke University Medical Center, Durham, NC 27710, USA.
Epilepsy Behav. 2009 Jan;14 Suppl 1(Suppl 1):65-73. doi: 10.1016/j.yebeh.2008.08.020. Epub 2008 Oct 1.
Virtually all mammals, including humans, exhibit neurogenesis throughout life in the hippocampus, a learning and memory center in the brain. Numerous studies in animal models imply that hippocampal neurogenesis is important for functions such as learning, memory, and mood. Interestingly, hippocampal neurogenesis is very sensitive to physiological and pathological stimuli. Certain pathological stimuli such as seizures alter both the amount and the pattern of neurogenesis, though the overall effect depends on the type of seizures. Acute seizures are classically associated with augmentation of neurogenesis and migration of newly born neurons into ectopic regions such as the hilus and the molecular layer of the dentate gyrus. Additional studies suggest that abnormally migrated newly born neurons play a role in the occurrence of epileptogenic hippocampal circuitry characteristically seen after acute seizures, status epilepticus, or head injury. Recurrent spontaneous seizures such as those typically observed in chronic temporal lobe epilepsy are associated with substantially reduced neurogenesis, which, interestingly, coexists with learning and memory impairments and depression. In this review, we discuss both the extent and the potential implications of abnormal hippocampal neurogenesis induced by acute seizures as well as recurrent spontaneous seizures. We also discuss the consequences of chronic spontaneous seizures on differentiation of neural stem cell progeny in the hippocampus and strategies that are potentially useful for normalizing neurogenesis in chronic temporal lobe epilepsy.
几乎所有哺乳动物，包括人类，在其一生中大脑的学习和记忆中心海马体中都会发生神经发生。在动物模型中的大量研究表明，海马体神经发生对于学习、记忆和情绪等功能很重要。有趣的是，海马体神经发生对生理和病理刺激非常敏感。某些病理刺激，如癫痫发作，会改变神经发生的数量和模式，不过总体影响取决于癫痫发作的类型。急性癫痫发作传统上与神经发生增加以及新生神经元迁移到异位区域（如齿状回的门区和分子层）有关。更多研究表明，异常迁移的新生神经元在急性癫痫发作、癫痫持续状态或头部受伤后典型出现的致痫性海马回路的发生中起作用。反复自发性癫痫发作，如在慢性颞叶癫痫中通常观察到的那样，与神经发生显著减少有关，有趣的是，这与学习和记忆障碍以及抑郁同时存在。在这篇综述中，我们讨论了急性癫痫发作以及反复自发性癫痫发作所诱导的异常海马体神经发生的程度和潜在影响。我们还讨论了慢性自发性癫痫发作对海马体神经干细胞后代分化的影响以及可能有助于使慢性颞叶癫痫中的神经发生正常化的策略。
