X线照射对实验性癫痫大鼠脑皮层氨基酸递质含量的影响

目的 探讨癫痫大鼠放射治疗的作用机制与时间、合理剂量。方法 利用慢性点燃癫痫大鼠进行24、12、6、0Gy的X线照射，用氨基酸分析仪测定不同照射剂量癫痫大鼠及照射后1h、24h、1周时癫痫大鼠额叶皮层内的主要兴奋性与抑制性氨基酸递质含量变化。结果 X线放射治疗后发生变化的氨基酸递质主要是G1u与GABA，与对照组(0Gy)比较，12Gy、24Gy组Glu含量降低，GABA含量升高，Glu／GABA值降低；照射后1h、24h、1周后GABA含量升高，Glu／GABA值降低，其中以24h比值下降最为明显。结论 放射治疗癫痫的机制主要是GABA与Glu递质发生快速而持续的变化；癫痫大鼠接受12Gy的放射治疗较为合理。

Effect of X-ray on amino-acid transmitters in brain of epileptic rat

Objective To investigate the effective mechanism, time and rational dose of radiotherapy of epileptic rat. Methods To make rat model of epilepsy, and give 0, 24,12 or 6Gy X ray irradiation, and then detect the amino-acid contents in frontal lobe of those rats in 1 hour, 24 hours or 1 week after radiotherapy. Results Glu and GABA are the key amino-acids in radio effection. After 12Gy or 24Gy irradiation there were low Glu, high GABA and low Glu/GABA in frontal lobe of rat. After 1h, 24h and 1 week irradiation, the contents of GABA raised up while the ratio of Glu/GABA declined with a remarkable decline at 24h. Conclusions Radiotherapy to epileptic rat may set off a rapid and enduring change of GABA and Glu transmitters, and 12Gy may be the rational radio dose for epileptic rat.