慢性癫大鼠海马电压依赖性钙通道α1亚单位mRNA的研究

Changes in Voltage-dependent Calcium Channel α1-subunit mRNA in Chronic Epileptic Rat Hippocampus

目的:研究Ca2+及其通道mRNA在癫发病中的作用。方法:采用半定量原位杂交和Northern杂交技术,对戊四氮慢性致大鼠在致不同时段海马内电压依赖性钙通道(VDCC)α1亚单位mRNA的表达变化进行了研究。结果:实验大鼠在癫形成早期海马不同亚区内α1A、α1D、α1E亚单位mRNA表达水平较对照组明显升高,α1B亚单位mRNA在CA1区和齿状回表达水平下降,而α1C-Ⅰ、α1C-Ⅱ表达无明显变化。充分点燃期仅α1B亚单位mRNA水平在CA3区明显升高。最后一次癫发作后第28天,各亚单位无明显变化。结论:在致过程中,VDCCα1亚单位mRNA有不同程度的变化,其结果可能通过改变神经递质的释放模式而在癫灶形成中起一定作用。

Aim： To explore the pathogenesis of calcium and calcium channel mRNA in epilepsy. Methods： Using semiquantitative in situ hybridization and Northern blot techniques, we studied the changes of voltage-dependant calcium channels α1 subunit mRNA in chronic epileptic rat hippocampus at different periods.Results： During the initial stages of epileptogenesis, the α1A, α1D and a1E-subunit mRNA levels were significantly increased in the different hippocampal subareas in comparison to the levels in control animals. In contrast,a1B-subunit gene expression decreased in the CA1 area and dentate gyrus. No significant change was observed in the α1C-Ⅰ ,α1C-Ⅱ expression. At fully kindled stage, only α1B-subunit mRNA level was increased in CA3 area. No significant change was observed at long term. Conclusion： Voltage-dependent calcium channels α1 subunit mRNA expression is altered in hippocampal subareas during the early stage of epileptogenesis and may underline the establishment of a epileptic focus, possibly caused by changing the release model of neurotransmitter.