玻璃体内注射谷氨酸导致大鼠视网膜Müller细胞内ERK12磷酸化水平增高.docx

玻璃体内注射谷氨酸导致大鼠视网膜Müller细胞内ERK1/2磷酸化水平增高 作者：周润海　严宏　段小莉　王百忍 【关键词】 谷氨酸　　cnIntravitreal glutamate injection induces an increased phosphorylation of ERK1/2 in retinal Müller cells of rats　　【Abstract】 AIM: To analyze the changes of phosphoERK1/2 in retinal Müller cells by using an intravitreal glutamate insult and to explore the neuroprotection role of activated (phosphorylated) ERK1/2 against glutamate cytotoxicity in retina. METHODS: A 2 μL of saline or glutamate (375 nmol) was injected into the random unilateral vitreous body for 3 d or 7 d in 18 SD rats. The rats were randomly divided into 3 groups: Control group (saline injections), glutamate injections 3 d group and glutamate injections 7 d group. The changes of the activated ERK1/2 were studied by immunohistochemical staining and computerpicture analytic system. RESULTS: After 7 d intravitreal glutamate insult, the activated phenotypes of retinal cells exhibited a hypertropic morphology and increased immunostaining for ERK1/2. By the staining pattern in shape and localization, the positive cells were presumed to be Müller cells. The gray level of glutamate injections 7 d group was the lowest among the 3 groups. The difference between glutamate injections 7 d group and other two groups was significant (Plt;005). CONCLUSION: Increased phosphorylated ERK1/2 in retinal Müller cells by using an intravitreal glutamate insult suggests that phosphoERK1/2 plays an important neuroprotective role when retinal ganglion cells are injured by glutamate cytotoxity.　　【Keywords】 glutamic acid; retinal Müller cells; ERK1/2　　【摘要】 目的： 观察大鼠玻璃体内注射谷氨酸后视网膜Müller细胞内ERK1/2分子的磷酸化水平，为探讨ERK1/2通路的激活在谷氨酸毒性损伤视网膜时的保护作用提供形态学证据.方法： SD大鼠18只，随机分为生理盐水对照组、谷氨酸注射后3 d组和7 d组，每组6只.随机选取大鼠的一只眼进行玻璃体内注射，实验组注射谷氨酸(375 nmol) 2μL， 对照组注射等量生理盐水，注射后3或7 d后，取出眼球作冰冻切片，采用免疫组化法显示视网膜中的含磷酸化ERK1/2的阳性结构，用图像分析比较对照组和不同实验组的平均灰度值.结果： 注射谷氨酸7 d组的视网膜Müller细胞内ERK1/2表达上调，其灰度值（9700±221）比对照组灰度值（12800±323）和注射谷氨酸3 d组的灰度值（1