脑内灌流6-羟基多巴胺对大鼠纹状体细胞外液氨基酸类神经递质的影响及美多芭的作用

目的探讨脑内灌流6-羟基多巴胺(6-OHDA)对大鼠纹状体细胞外液氨基酸类神经递质的影响以及美多芭的作用。方法SD大鼠,随机分为对照组、模型组及美多芭高、低剂量组。采用微透析技术脑内灌流6-OHDA造模,邻苯二甲醛柱前衍生,高效液相-荧光检测技术,动态监测清醒自由活动大鼠纹状体细胞外液氨基酸神经递质水平。结果6-OHDA脑内灌流40 min后,模型组大鼠纹状体细胞外液谷氨酸(Glu)浓度有4个时间点、γ-氨基丁酸(GABA)浓度有1个时间点、牛磺酸(Tau)浓度有8个时间点较对照组升高(P<0.05或P<0.01)。美多芭高、低剂量组与模型组比较分别有5个和4个时间点Glu浓度降低、有7个和2个时间点GABA水平升高(P<0.05或P<0.01)。结论6-OHDA脑内灌流引起大鼠纹状体细胞外液氨基酸类神经递质变化,美多芭可以剂量依赖性地抑制其引起的Glu升高,并进一步增加GABA的浓度。

The effect of extracellular amino acid neurotransmitters in striatum of rats by intracerebral perfusion of 6-OHDA and Madopar intervene

Aim To explore the change in the extracellular level of amino acid neurotransmitters in striatum of rats induced by intracerebral perfusion of 6-hydroxy dopamine(6-OHDA) and the impact of Madopar.Method SD rats were randomly divided into four groups: control,model,low-dose madopar(madopar L) and high-dose madopar(madopar H).The model was established through intracerebral perfusion of 6-OHDA using microdialysis technique.The concentration of extracellular amino acids in striatum of free-moving rats was dynamically measured by Phthalic dicarboxaldehyde(OPA) pre-column derivatization and high performance liquid chromatography-fluorescence detector(HPLC-FLD).Results After 40 min of the perfusion with 6-OHDA in brain of rats,compared with the control group,Glu,GABA and Tau in model group increased significantly at 4,1 and 8 time points respectively(P<0.05 or P<0.01);compared with the model group,Glu decreased at 5 time points(madopar H) and 4 time points(madopar L);while GABA increased at 7 time points(madopar H) and 2 time points(madopar L)(P<0.05 or P<0.01).Conclusions Intracerebral perfusion of 6-OHDA can change the extracellular level of amino acid neurotransmitters in striatum of rats.Madopar can inhibit the increase of Glu while increase the release of GABA in a dose-dependent manner.