原儿茶酸防护百草枯致胎鼠中脑细胞损伤实验研究

目的观察原儿茶酸（PCA）对百草枯（PQ）所致胎鼠中脑神经细胞损伤的保护作用。方法取胚胎大鼠进行中脑神经细胞分离培养,随机分为空白对照组、阳性对照组、PQ组及PCA高、低浓度组（100μmol/L和50μmol/L）,分别给予神经生长因子（NGF）、PQ和PCA进行配组干预,接种第6天除空白对照组,另四组均加入PQ终浓度为800μmol/L。接种第7天观察细胞生长状况。四唑盐（MTT）比色法检测神经细胞活性,抗酪氨酸羟化酶（TH）免疫荧光染色法测定多巴胺（DA）能神经元数量;TH免疫荧光染色比较各组阳性神经元数目及细胞核、轴突的变化情况。结果与空白对照组、阳性对照组、PCA组比较,PQ组细胞核固缩、破裂,细胞凋亡率升高;PCA高、低浓度预处理后,细胞存活率增加（P〈0.05）,细胞轴突损伤减少,细胞凋亡率降低,且具有量-效关系。结论 PCA对PQ诱导的中脑神经细胞凋亡具有抑制作用,该作用有浓度依赖性,提示PCA对胎鼠中脑神经细胞及DA能神经元有一定的保护作用。

Protective Effect of Protocatechuic Acid on Paraquat-induced Mesencephalic Cell Damage in Fetal Rats

Objective To investigate the protective effect of protocatechuic acid（PCA） on paraquat（PQ）-induced midbrain neural stem cell injuries of fetal rats.Methods The midbrain neural stem cells of fetal rats were isolated and cultured,and then the cells were divided into control group,positive control group,PQ group,and PCA groups（100 and 50μmol/L）.On day 3,the cells were treated with nerve growth factor（NGF）,PQ and PCA to observe the growth status of cells.On day 6,except for control group,the cells in other 4 groups were treated with PQ of 800 μmol/L.MTT assay was used to detect neural cell activity and the number of dopaminergic（DA） neurons was determined with antibodies of tyrosine hydroxylase（TH） by immunofluorescence.The neural cellular morphology,counts,and axons were compared among different groups.Results Compared with control group,positive control group,and PCA groups,cell survival was decreased,and cell chromatin pyknosis and apoptosis was increased in PQ group（P〈0.05）;After treatment with two doses of PCA,cell survival was increased（P〈0.05） and cell axonal injury was reduced and apoptosis was decreased in a dose-effect manner.Conclusion PCA has an inhibitory effect on apoptosis of embryonic rat mesencephalic cells induced by PQ,and this effect is concentration dependent.This indicated that Tip PCA had a protective effect on primary cultured mesencephalic cells and DA neurons.