乐果对大鼠皮层神经元氧化损伤及兴奋性氨基酸递质含量的影响

Effect of dimethoate on primary cultured rat cortical neuron

目的观察乐果染毒对原代培养的大鼠皮层神经元的的毒性作用及损伤机制。方法体外原代培养SD大鼠皮层神经元6d后，加入终浓度为1、5、10、50、100μmol／L的乐果，于染毒后48h收获细胞，取匀浆上清液用于氧化损伤及细胞内兴奋性氦基酸递质的测定，流式细胞术检测细胞凋亡。结果染毒48h后。乐果浓度在5、10、50、100μmol／L时，超氧化物歧化酶（SOD）活力[（1．04±0．02）、（0．99±0．02）、（0．96±0．02）、（0．91±0．02）U／rag prol即明显降低，谷胱甘肽（GSH）含量[（219．35±6．79）、（205．6±6．29）、（194．06±2．63）、（93．68±7．56）mg／g pro]明显降低，丙二醛（MDA）含量[（21．22±0．29）、（24．01±0．34）、（27．15±1．02）、（32．91±1．39）nmol／mg pro]明显升高，与对照组比较，差异均有统计学意义（P〈0．01）；10、50、100μmol／1．剂量组大冬氨酸含镀明显升高，1、5、10、50、100μmol／L剂量组谷氨酸含量明显升高，与对照组比较，差异均有统计学意义（P〈0．01）；1、10、100μmol／L染毒组乐果对神经元细胞凋亡影响明显。乐果染毒后，神经元内MDA含量与兴奋性氨基酸（天冬氨酸、谷氨酸）含量呈正相关，相关系数分别为0．937和0．759；而与GSH含量呈负相关，相关系数分别为-0．868和-0．801，有统计学意义（P〈0．01）。结论乐果可引起神经元氧化损伤及兴奋性氨基酸递质含量变化，共同参与神经元的凋亡过程。

Objective To investigate the effect and mechanisms of dimethoate on the primary cultured cortical neuronal cell injury. Methods Cortical neuronal cells were isolated and cultured in serum free medium for 6 days in vitro,and 1,5,10,50 and 100 μmol/L dimethoate were added to the medium and intraeellular SOD,MDA and GSH. The content of excitatory amino acid was measured after 48hours. Flow cytometry was used to detect the neuronal cell apoptosis. Results After 48 h ,the activity of SOD and the content of GSH decreased [（ 1.04±0.02 ）, （ 0.99±0.02 ）, （0.96±0.02）,（ 0.91 ±0.02 ） U/rag proⅡ（ 219.35 ±6.79 ）, （205.6±6.29）, （ 194.06±2.63 ）. （ 93.68 ±7.56 ） mg/g pro], and the content of MDA increased obviously with 5,1 0, 50 and 1 00 μmol/L dimethoate [（ 21.22 ±0.29 ）, （ 24.01 ±0.34 ）, （ 27.15 ± 1.02 ）, （ 32.91 ± 1.39 ） nmol/mg pro];The content of Asp from 10 to 100 μmol/L dose group was higher than the control group and the content of Glu from 1 to 100 μmol/L dose group was higher than the control group. The apoptosis rate had great significance between 1 to 100 μmol/L dose groups and control group. When treated with dimethoate,MDA content in neuron was positively correlated with the content of EAAs with the increase of dimethoate. The correlative coefficient was 0.937 and 0.759 respectively（P〈0.01 ）,while it was negatively correlated with the content of GSH. The correlative coefficient was -0.868 and -0.801 respectively（P〈0.01 ）. Conclusion The oxidative damage and changes of excitatory amino acid content induced by Dimethoate contribute to the primary cultured rat cortical neuron apoplosis.