地塞米松对鼠脑缺血-再灌注损伤时海马谷氨酸转运体功能的影响

目的 探讨地塞米松对大鼠脑缺血－再灌注损伤时海马谷氨酸转运体功能的影响及其与自由基的关系。方法 采用大鼠三动脉夹闭,松夹制作脑Ｉ－Ｒ模型,利用海马突触膜颗粒对＾３Ｈ－Ｌ谷氨酸摄入量的测定及分光光度法测定了海马谷氨酸转运体,超氧化物歧化酶活性及丙二醛含量的变化。结果 与对照组相比,Ｉ－Ｒ组海马谷氨酸转运体的功能及ＳＯＤ活性降低;ＭＤＡ含量升高。

The Influence of Dexamethasone on Glutamate Transporter Function of Hippocampus in Rats with Injury of Cerebral Ischemia-reperfusion

Objective To investigate the effect of dexamethasone on glutamate transporter function in hippocampus of ischemia reperfusion injuny (I R) rats and the relationship to free radicals. Method A model of I R was established by clipped three arteries and then released to reperfuse blood into brain in rats. Glutamate transporter function, MDA content and SOD activity were studied by means of assay of 3H L glutamate uptake in hippocampal synaptosomes and spectrophotometry. Results The hippocampus glutamate transporter function and SOD activity in I R group were significantly decreased ( q =3 75, 5 72, P <0 05, 0 01) and content of MDA were increased ( q =3 79, P <0 05) , compared with control group. Glutamate transporter function and SOD activity in dexamethasone group were increased ( q =5 21, 3 50, P <0 01, 0 05) and content of MDA were decreased ( q =3 61, P <0 05) compared with I R group. Conclusion Dexamethasone could improve glutamate transporter function in hippcampus of I R rats. The mechanism might be related to elimination of oxygen free radicals.$$$$