苯妥英钠对神经元细胞内外谷氨酸含量及胞内[Ca^(2+)]的影响

Effect of Phenytoin on Glutamate and[Ca^(2+)]\-i of Cultured neurons from\;Cerebral Cortex

用高效液相色谱法测定 30 μm、6 0 μm PHT作用下培养神经元细胞内及分泌到细胞外谷氨酸的含量。并同时用放射酶测定法测定细胞内谷氨酸脱羧酶及 FA- 2 /AM法测细胞内游离 Ca2 + 的变化情况。结果示苯妥英钠作用下细胞内谷氨酸含量及谷氨酸脱羧酶活性无变化 ,细胞内 Ca2 +一过性降低 ,细胞分泌谷氨酸水平明显降低。说明苯妥英钠可能是通过降低细胞内Ca2 +浓度 ,减少细胞对兴奋性神经递质谷氨酸的分泌而发挥药理作用。

The high performance liquid chromatography method was used to determine the intracellular and extracellular glutamate(Glu)under the influence of 30μm,60μm phenytoin(PHT).At the mean time the activity of glutamic decarboxylase(GAD)was measured by radio enzymeassay and the cytosolic free calcium([Ca\+\{2+\}]\-i)was measured by Fura 2/AM method.The results showed that there were a remarkable decrease(P<0.05)of extracelluar glutamate and a transient decrease of cytosalic free calcium,under the performance of 30μm,60μm phenytoin,but there were no change on intracellular glutamate and the activity of glutamic decarloxylase.It was suggested that the effect of phenytoin is dependent on the transient decrease of[Ca\+\{2+\}]i and then decreasing the secretion of glutamate.