百草枯对小鼠黑质多巴胺能神经元的选择性损害

目的:探讨百草枯对黑质部多巴胺能神经元的损害是否具有选择性。方法:用口服百草枯的途径,建立小鼠帕金森病模型;应用原位杂交技术观察DAT和VMAT2在不同脑区的mRNA表达水平并测定两者的比值,采用细胞计数观察百草枯干预后多巴胺能神经元的损害。结果:在黑质部DATmRNA和VMAT2mRNA的比值最高;在红核和下丘脑室旁核区域DATmRNA与VMAT2mRNA的比值和黑质部相比较低(P<0·01)。百草枯干预后黑质部的多巴胺能神经元减少37·7%;红核和下丘脑室旁核区的多巴胺能神经元分别减少12·2%和13·1%。结论:百草枯对黑质部多巴胺能神经元的损害具有相对选择性,其原因可能与黑质部DATmRNA和VMAT2mRNA的比值高有关。

Selective Damage of Paraquat on Dopaminergic Neurons in Substanti Nigra of Mice

Aim:To explore whether paraquat could damage dopaminergic neurons selectively in substantia nigra of parkinsonian mice induced by paraquat taken orally.Methods:In situ hybridization technique was applied to observe the mRNA expressions of DAT and VMAT 2 in different areas of brain. The ratio of DAT mRNA to VMAT 2 mRNA and the degree of neurons injury in different areas of brain were also observed after the paraquat treatment. Results:It was found that the ratio of DAT mRNA to VMAT 2 mRNA was the highest in substantia nigra, whereas lower in red nucleus and paraventricular hypothalamic nucleus. The dopaminergic neuron was decreased by 37.7% in substantia nigra whereas 12.2% and 13.1% respectively in red nucleus and paraventricular hypothalamic nucleus after paraquat given orally for two months.Conclusion:The results indicated that the loss of dopaminergic neurons in substantia nigra induced by paraquat may be selective, which was possible related to a higher ratio of DAT mRNA to VMAT 2 mRNA in substantia nigra.