大鼠额叶皮质损害和胚脑移植的脑电地形图及形态学研究

TRANSPLANTATION OF FETAL NEOCORTEX INTO INJURED FRONTAL CORTEX OF ADULT RATS: A BEAM AND MORPHOLOGICAL STUDY

用ＮＤＣ－２００型脑电地形图仪对单侧额叶皮质损害及损害后移植胚脑皮质的大鼠进行脑电功率谱及脑电地形图（ＢＥＡＭ）的检查。结果发现大鼠伤侧额叶皮质Ｄｅｌｔａ（δ）波和Ｔｈｅｔａ（θ）波与Ａｌｐｈａ（α）波和Ｂｅｔａ（β）波（ＤＴ／ＡＢ）之比明显高于健侧（Ｐ＜０．０５）。损害后３ｄ、２周、４周、８周，其结果无差别。额叶皮质损害后２周鼠接受了胚脑皮质移植，移植鼠存活２个月和５个月时再次进行脑电功率谱的检查，发现损害后２周移植鼠在２个月时即已呈现两侧ＤＴ／ＡＢ之比相接近（Ｐ＞０．０５）。形态学观察发现，皮质缺损处均有存活良好的移植物，脑电地形图表现左右功率值相近似的动物，其移植区较大。选功率值左右对称动物，在处死前在健侧皮质注射荧光素快蓝（ｆａｓｔｂｌｕｅ，ＦＢ），在移植侧丘脑注射ＤｉａｍｉｄｉｎｏＹｅｌｏｗ（ＤＹ），在移植区发现有少量标记的ＦＢ及ＤＹ细胞。但其密度较其周围宿主皮质内标记细胞为低。表明移植物与宿主脑有可能重建丘脑、皮质神经环路。ＮＡＤＰＨ－ｄ组织化学染色结果发现，移植区有ＮＯＳ阳性纤维伸入宿主皮质，并见宿主皮质ＮＯＳ阳性神经元突起伸向移植区，表明两者相互整合。以上结果提示，脑内移植治疗脑外伤是具有功?

Unilateral frontal cortex lesioned rats receiving fetal neocortex transplantation were examined with power spectrum analysis and topographic mapping of EEG referenced to as brain electrical activity mapping (BEAM). In lesioned side, the value of delta+theta/alpha+beta(DT/AB) were significantly higher than those of the control side ( P <0 05), and there are no differences between 3 days , 2 weeks , 4 weeks, and 2 months lesioned rats. Fetal cortex tissue were grafted into the lesioned cortex of rats 2 weeks post lesion. After two or five months survival period, host animals were received another two times power spectrum analysis. The values of DT/AB in lesioned side were already similar to the healthy side ( P >0 05) either in 2 or 5 months survival rats. The morphological observations found that the grafts in the lesioned cortex were survival well in the host animals, but the extent of the graft area was larger in rats with equal values of DT/AB at bilateral sides. Injection of fast blue (FB) and diamidino yellow (DY) into the host contralateral cortex and ipsilateral thalamus were carried respectively in animals with equal value of (DT/AB) at bilateral sides. Scattered FB and DY labeled neurons were seen in the grafts. The density of the labeled neurons in graft areas were lower than those of labeled cells in the host cortex surrounding the transplants. The presence of callosal and thalamic projections from graft to host suggest that reconstruction of damaged neural circuity is possible. NADPH d histochemistry results showed that NADPH d positive fibers extended from graft to host and host′s NADPH d positive neurons proiected its processes into the graft area. Indicate the integration of tissues between host and graft.These suggest that the neural transplantation might induce sufficient functional effects in curing the brain injury and the power spectral analysis may be a good method for investigating the function of central nervous system.