红藻氨酸致颞叶癫(癎)大鼠脑内Semaphorin3A、Semaphorin4C基因表达的研究

目的研究轴索导向分子Semaphorin3A(Sema3A)、4C(Sema4C)对癫大鼠海马苔藓纤维重建的调控作用及对皮层神经元的保护作用。方法大鼠侧脑室内注射红藻氨酸制备颞叶癫模型,原位杂交法检测致痫间后1d,1、2、3、4周大鼠脑内Sema3A/Sema4C mRNA表达。结果致痫间后1周Sema3A、Sema4CmRNA分别在齿状回(DG),CA3区表达明显下降(P<0.01),持续至3、4周时恢复至正常(P>0.05);致痫间后1d Sema3A mRNA在皮层表达明显下降(P<0.01),持续至1、2周后恢复至正常(P>0.05)。结论红藻氨酸致痫间后DG及CA3区神经元分别下调Sema3A/Sema4C mRNA的表达,促进癫大鼠苔藓纤维重建;皮层神经元通过下调Sema3A mRNA的表达来维持自身存活。

Semaphorin3A,semaphorin4C gene expression in rat brain after kainic acid-induced temporal lobe epilepsy

Objective To study the guidance functions of the axon guidance molecules,semaphorin3A (Sema3A) and semaphorin4C (Sema4C),in mossy fiber sprouting and protection of cortex neurons after kainic acid (KA)-induced temporal lobe epilepsy (TLE).Methods Rat temporal lobe epilepsy was induced by intraventriculation of KA 1 d,1 w,2 w,3 w,4 w after KA-induced seizures,Sema3A/Sema4C mRNA expression was detected by insitu hybridization.Results Compared with the control group,Sema3A mRNA expression in the DG area and Sema4C expression in the CA3 area decreased one week after KA-induced SE (P<0.01),continuing to 3 w,then increased to a normal lever from the fourth week (P>0.05);Sema 3A mRNA expression decreased in the cerebral cortex (P<0.01) one day after KA-induced SE,continuing to 1 w,then increased to a normal lever in the 2 w(P>0.05).Conclusions The results suggests that after KA-induced SE,the Sema3A/Sema4C mRNA expression down regulated in the neurons of DG/CA3 area and thus contribute to mossy fiber sprouting cortex neuron down regulates Sema3A mRNA expression thus to protect themselves.