高浓度苯丙氨酸对胚鼠皮层神经元Ca^(2+)水平和ERK活性的影响  

Effects of phenylalanine on cytoplasmic free Ca^(2+) level and ERK activity in cultured embryonic rat cortical neurons

作　　者：李端[1] 顾学范[1] 黄成娇[1] 余永国[1] 张拥军[1] 

机构地区：[1]上海交通大学医学院新华医院上海市儿科医学研究所,上海200092

出　　处：《上海交通大学学报（医学版）》2009年第5期492-495,共4页Journal of Shanghai Jiao tong University:Medical Science

基　　金：国家自然科学基金(30570689);国家高技术研究发展计划(2007AA02Z447);国家科技支撑计划课题(2006BAI05A07)~~

摘　　要：目的探讨高浓度苯丙氨酸(Phe)对体外培养的胚鼠皮层神经元突起生长、胞内Ca2+水平和细胞外信号调节激酶(ERK)活性的影响。方法根据加入Phe的浓度,将体外培养的原代胚鼠皮层神经元随机分为5组:0.45、0.9、3.6、5.0 mmol/LPhe组和对照组(加PBS)。采用细胞免疫化学方法检测各组神经元最长突起长度;激光共聚焦显微镜下观察在5.0 mmol/L Phe作用下,神经细胞内Ca2+水平的变化;采用Western blotting检测5.0 mmol/L Phe作用下的ERK磷酸化水平。结果0.9、3.6和5.0 mmol/L Phe组神经元最长突起长度较对照组明显缩短(P<0.05),且呈浓度依赖性。5.0 mmol/L Phe作用于神经元后,胞内Ca2+水平迅速降低,1 min达到最低水平,随后缓慢回升。5.0 mmol/L Phe作用5、10和30 min时能降低皮层神经元ERK磷酸化水平,p-ERK与ERK的比值分别为对照组的(73.7±3.0)%、(35.9±2.0)%和(80.2±8.5)%(P<0.05)。结论高浓度Phe能够降低皮层神经元细胞质内Ca2+和ERK磷酸化水平,从而干扰大脑皮层神经元的正常生长发育。Objective To investigate the effects of high concentrations of phenylalanine （Phe） on intracellular freeCa^2＋ concentrations, extracellular signal-regulated kinase （ERK） activity and neurite outgrowth in cultured cortical neurons. Methods Neurons derived from cerebral cortex of embryonic rats were cultured in vitro and then were randomly divided into five groups： control group （PBS）, 0. 45 mmol/L Phe group, 0.9 mmol/L Phe group, 3.6 mmol/L Phe group and 5.0 mmol/L Phe group. Immunocytochemistry was used to detect the longest length of neurite outgrowth. Intracellular Ca^2＋ level induced by 5.0 mmol/L Phe was determined by laser confocal microscopy. Western blotting was employed to detect the influence of 5.0 mmol/L phenylalanine on the ERK activityl Results Neurite outgrowth of cultured cortical neurons was inhibited by 0.9, 3.6 and 5.0 mmol/L Phe, and the effect was in a concentration-dependence way. The concentration of free Ca^2＋ in cortical neurons decreased to the minimal level within the first minute after stimulation by 5.0 mmol/L Phe, and then slowly recovered to the basal level. Compared with control group, the ERK activity （ expressed as percent of the control） in 5.0mmol/LPhe group within 5, 10 and 30 rain were （73.7 ±3.0）%, （35.9 ±2.0）% and （80.2 ±8.5）%, respectively（P 〈 0.05） . Conclusion High concentration of Phe might interfere with the normal development of cerebral cortical neurons through influencing the Ca^2＋ level and ERK activity.

关 键 词：苯丙氨酸 神经突起 钙离子 细胞外信号调节激酶 

分 类 号：R363[医药卫生—病理学]