Vicedomini J P, Nadler J V
Department of Pharmacology, Duke University Medical Center, Durham, NC 27710.
Brain Res. 1990 Mar 26;512(1):70-4. doi: 10.1016/0006-8993(90)91171-c.
A study of seizure activity and neuronal cell death produced by intracerebroventricular kainic acid had suggested that seizures conveyed by the hippocampal mossy fibers are more damaging to CA3 pyramidal cells than seizures conveyed by other pathways. To test this idea, the effects of a unilateral mossy fiber lesion were determined on seizure activity and neuronal degeneration provoked by repetitive electrical stimulation of the hippocampal fimbria in unanesthetized rats. Fimbrial stimulation resulted in self-sustained status epilepticus accompanied by neuronal degeneration in several brain regions, including area CA3 of the hippocampal formation. A unilateral mossy fiber lesion more readily attenuated the electrographic and behavioral seizures provoked by fimbrial stimulation than those provoked by kainic acid. If status epilepticus developed in the presence of a mossy fiber lesion, denervated CA3 pyramidal cells were still destroyed, although similar lesions protect these neurons from kainic acid-induced status epilepticus. Thus the two models of status epilepticus employ somewhat different seizure circuitries and neurodegenerative mechanisms. Seizures which involve the mossy fiber projection are not necessarily more damaging to CA3 pyramidal cells than seizures which do not.
一项关于脑室内注射海藻酸所产生的癫痫活动和神经元细胞死亡的研究表明，海马苔藓纤维传导的癫痫发作对CA3锥体细胞的损害比其他途径传导的癫痫发作更大。为了验证这一观点，研究了单侧苔藓纤维损伤对未麻醉大鼠海马伞重复电刺激诱发的癫痫活动和神经元变性的影响。海马伞刺激导致自我维持的癫痫持续状态，并伴有包括海马结构CA3区在内的几个脑区的神经元变性。单侧苔藓纤维损伤比海藻酸诱发的癫痫更容易减轻海马伞刺激诱发的脑电图和行为性癫痫发作。如果在存在苔藓纤维损伤的情况下发生癫痫持续状态，去神经支配的CA3锥体细胞仍然会被破坏，尽管类似的损伤可保护这些神经元免受海藻酸诱导的癫痫持续状态的影响。因此，两种癫痫持续状态模型采用的癫痫发作电路和神经退行性机制略有不同。涉及苔藓纤维投射的癫痫发作对CA3锥体细胞的损害不一定比不涉及的癫痫发作更大。
