大鼠额叶皮质损害后胚脑移植适宜时期的探讨

The Suitable Period For Fetal Neocortex Transplantation After Frontal Cortex Injury In Rats

目的:探讨脑外伤后进行脑组织移植的适宜时期。方法:机械抽吸法制作大鼠右侧额叶皮质损害模型。在大鼠额叶皮质损害后立即、2周及2月时采用铺片法将E15-17天胚脑额叶皮质移植入皮质损害腔内。动物存活2月再进行脑功能测试和形态学观察。结果:额叶皮质损害后立即移植鼠移植侧δ、0频段相对功率值显著高于健侧(P<0.05),α、β频段相对功率值显著低于健侧(P<0.05),脑电功率谱曲线两侧明显不对称,表明受损的脑功能也没有恢复。额叶皮质损害后2周及2月移植鼠移植侧δ、0、α、β频段相对功率值均与健侧近似(P>0.05),脑电功率谱曲线两侧基本对称,脑电功率谱改善。形态学观察可见损害后立即移植鼠少见有移植组织存活,损害后2周及2月移植鼠,绝大多数见有良好的移植组织存活。结论:大鼠额叶皮质损害后2周至2月均为胚脑组织移植适宜时期。

Objective:To explore the suitable time for fetal neocortex transplantation after frontal cortex injury in rats. Methods:The right frontal cortex lesioned models were made by gentle aspiration and E 15 - 17 fetal neocortex were transplanted immediately after injury or at 2 weeks or 2 months postlesion, respectively. After two months survival periods, all the grafted animals received EEg power spectral analysis and morphological study. Results: The relative power of the cerebral hemisphere receiving graft immediately after injury were significantly increased in delta and theta bands and decreased in alpha and beta bands compared with those of the healthy sides(P< 0.05 ), and the power spectral curves at grafting sides and healthy sides were asymmetrical. In the rats' brain which received graft at 2 weeks or 2 months postlesion, the relative power at grafting sides either in delta, theta,alpha,or beta bands was similar to healthy sides(P >0.05) ,and their power spectral curves at both sides showed symmetrical. The morphological observation showed that only two small grafts with no functional effects were seen in eight rat's brain which received implant immediately after injury. However,in the rats which received graft either at 2 weeks or 2 months postlesion, the neural grafts survived well, with sufficient functional effects.Conclusion:These results indicate that the is from 2 weeks to 2 months postlesion.