中文摘要：

目的探讨幼鼠惊厥持续状态（status convulsion，SC）后癫痫发生过程中胼胝体内有髓神经纤维（myelinated fibers, MF）的变化。方法选用21 d SD幼鼠122只，按随机数字表法分为对照组（n=48）及实验组（n=74）。实验组采用氯化锂匹罗卡品制备SC模型，应用无线遥测脑电图记录SC后癫痫发生不同时期脑电图变化；Gallyas银染观察胼胝体MF形态变化；Western blot检测胼胝体内髓鞘碱性蛋白（myelin basic protein, MBP）含量变化；透射电镜观察MF超微结构的改变。结果SC后不同时期脑电图的表现符合癫痫发生各阶段的变化；幼鼠SC后癫痫发生的慢性早期及慢性期胼胝体厚度明显变薄；与同龄对照组相比，幼鼠胼胝体内的MBP表达于SC后急性期即开始下降（P〈0.05），且潜伏期、慢性早期、慢性期均显著低于正常对照组（P〈0.01）；透射电镜可见大鼠SC后急性期胼胝体内MF开始出现分层、肿胀，慢性早期及慢性期还可见空泡化。结论幼鼠SC所致胼胝体内MF的损伤贯穿于SC后癫痫发生整个过程。

英文摘要：

Objective To study the change of myelinated fibers in corpus callosum of immature rats after status convulsion （SC） induced by lithium-pilocarpine. Methods Seventy-four immature SD rats, in which SC was induced by lithium chloride-pilocarpine （pilo group） and forty-eight immature SD rats （control group） were evaluated. Morphological changes of myelinated fibers in corpus callosum were examined by Gallyas staining. The expression of myelin basic protein （MBP） was determined by Western blotting. The micro-structural characteristics of myelinated fibers were determined by transmission electron microscopy at different time points （acute phase, latency phase, beginning of chronic phase and chronic phase）. Results It was found that the callosal myelinated fibers of the pilo group were degenerated, and the MBP expression in corpus callosum of the pilo group was significantly decreased in comparison with the control group at the acute phase lasting to the chronic phase after SC. While the myelinated nerve fibers in control rats were normal, with plasma membrane rings of regular heights and dense structure, the fibers in pilo-treated rats showed stratification, collapse and disruption, as well as disordered arrangement at different time points after SC. Conclusion Myelinated fiber damage in corpus callosum of immature rats is irreversible at acute phase after SC.