c－fos基因在听源性惊厥易感大鼠脑的表达──原位杂交组织化学法研究

运用原位杂交技术，以遗传性听源性惊厥易感大鼠Ｐ７７ＰＭＣ为对象，发现听源性惊厥可诱导大鼠脑内ｃ－ｆｏｓ基因快速、大量、短暂性表达。ｃ－ｆｏｓｍＲＮＡ分布于大脑皮层、梨状皮层、杏仁复合体、海马齿状回、上丘脑、背侧丘脑、下丘脑部分核团、下丘、蜗神经核、蓝斑及小脑等处。惊厥后皮层下结构中ｃ－ｆｏｓ基因表达变化程度超过皮层的变化，尤其是下丘、蜗神经核与惊厥时程有明显关系。推测皮层下结构对听源性惊厥的发生有重要意义。Ｐ＜０．０１讨论本文结果说明听源性惊厥同其它因素诱导的惊厥一样［３］，可诱导大鼠脑内ｃ－ｆｏｓ基因的表达，表达涉及到大脑皮层、海马齿状回、丘脑、下丘、蜗神经核等结构，其中以皮层下结构如丘脑、下丘、蜗神经核表达变化最显著。原位杂交显示的ｃ－ｆｏｓ基因表达特征类似于Ｎｏｒｔｈｅｒｎ杂交结果即快速、大量和短暂性。由于不同部位在惊厥活动中的作用差别，因此用原位杂交可以显示每一结构内ｃ－ｆｏｓ基因表达特点。如在惊厥后３０ｍｉｎ，海马齿状回中７０％以上的神经元单位胞质面积上银粒计数超过２０个，而梨状皮层及运动皮层仅占５～１３．８％。有报告指出海马齿状回为钙离子通道和ＮＭＤＡ受体高密度区域［４］，推测Ｃａ２＋和ＮＭＤＡ?

c-fos GENE EXPRESSION IN THE BRAIN OF AUDIOGENIC SEIZURE-PRONE RATS: AN IN STTU HYBRIDIZATION

Here we showed,using in situ hybridization technique, that audiogenic seizure can induce c-fos gene expression in brain of the genetical seizure-prone rat P77PMC. The character of c-fos gene expression was rapid,transient and in large amount of cells.Expression involved in the neocortex, piriform cortex. hippocampus, dentate gyrus, medial or lateral habenular nuclei. thalamus,hypothalamus, amygdala, inferior colliculus. periaqueductal gray, cerebellum, cochlear nucleus and locus coeruleus etc. Statistical analysis showed that the changes of c-fos mRNA level in subcortical regions after seizures was much significant than that of cortex and that the level of c-fos mRNA in inferior colliculus or cochlear nucleus was closely correlated with the time after seizure. It is suggested that the subcortical structure especially inferior colliculus might play important roles in the initiation and spreading etc.of audiogenic seizures.