摘要
采用微透析和高效液相色谱-电化学(HPLC-ECD)技术研究了谷氨酸和MK-801对正常和帕金森模型大鼠纹状体内多巴胺代谢的影响。用微透析技术在大鼠纹状体内分别定位给以左旋多巴、L-谷氨酸和/或MK-801,同时收集透析液,用HPLC-ECD方法测定透析液中多巴胺代谢产物的浓度。微透析和HPLC-ECD分析结果表明:纹状体内定位给以左旋多巴,正常大鼠和帕金森模型大鼠纹状体内多巴胺代谢产物的浓度均升高;纹状体内定位给以L-谷氨酸,可使正常大鼠纹状体内多巴胺代谢产物的浓度降低,但对帕金森大鼠模型纹状体内多巴胺代谢产物浓度的降低不显著;纹状体内定位给以MK-801,正常大鼠纹状体内多巴胺代谢产物的浓度升高;但对帕金森大鼠模型纹状体内多巴胺代谢产物浓度的升高不显著;纹状体内同时定位给以MK-801和L-谷氨酸,可以有效防止L-谷氨酸所致正常大鼠纹状体内多巴胺代谢产物浓度的降低。结果提示,谷氨酸可以通过NMDA受体调节多巴胺的代谢。尽管非竞争性NMDA拈抗剂MK-801可以有效防止L-谷氨酸所致正常大鼠纹状体内多巴胺代谢产物浓度的降低,但却不能有效地改善帕金森大鼠模型纹状体内多巴胺的代谢水平。因此在正常及帕金森病情况下,谷氨酸-多巴胺相互作用机制和MK-801改善帕金森病的机制还有待进一步研究。
The direct effects of glutamate and dizocilpine maleate (MK-801, non-competitive N-Methyl-.D-aspartate glutamate receptor antagonist) on the metabolism of dopamine were investigated in the striatum of normal and parkinsonian rats. L-dopa, L-glutamic acid and MK-801 were administered in the striatum locally by microdialysis. 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were simultaneously sampled by microdialysis. The concentrations of DOPAC and HVA were assayed by high performance liquid chromatography with electrochemical detection (HPLC-ECD). L-dopa increased the concentrations of DOPAC and HVA in the striatum of normal and parkinsonian rats. L-glutamic acid decreased the concentrations of DOPAC and HVA in striatum of normal rats but not parkinsonian rats. MK-801 increased the concentrations of DOPAC and HVA in the striatum of normal rats but not parkinsonian rats. MK-801 prevented the L-glutamic acid-induced decrease of DOPAC and HVA in the striatum of normal rats. Our results indicate that glutamate modulates the metabolism of dopamine (DA) through NMDA receptors and that the improvement of PD by MK-801 is not through improving the metabolism of DA.
出处
《生理学报》
CAS
CSCD
北大核心
2005年第1期71-76,共6页
Acta Physiologica Sinica
基金
This work was supported by Beijing youth Model culturing Funds for Science and Technolgy
关键词
帕金森病
微透析
大鼠
谷氨酸
MK-801
3
4-二羟基苯乙酸
高香草酸
Parkinson's disease
microdialysis
rat
glutamate
dizocilpine maleate
3,4-dihydroxyphenylacetic acid
homovanillic acid
