Age related interaction of dopamine and serotonin synthesis in striatal synaptosomes  

作　　者：MANOOCHEHR MESSRIPOUR AZADEH MESRIPOUR 

机构地区：[1]Department of Medical Biochemistry,Khorasgan Branch,Islamic Azad University,Isfahan,Iran [2]Medical Plant Research Center,Shahre Kord University of Medical Sciences,Iran

出　　处：《BIOCELL》2013年第2期17-21,共5页生物细胞（英文）

基　　金：supported by the Research Council of Khorasgan Branch,Islamic Azad University,Isfahan.

摘　　要：Tyrosine hydroxylase and tryptophan hydroxylase are key rate limiting enzymes in the biosynthesis of dopamine and serotonin,respectively.Since both enzymes are active in striatum,and affected by age,this study was undertaken to investigate interaction between dopamine and serotonin synthesis in brain striatal synaptosomes of aging rat.Male Wistar rats(3 and 30 month old)were killed by decapitation and brain striatal synaptosomes were prepared by discontinuous Ficoll/sucrose gradient technique.Synaptosomes were incubated in the presence of added pargiline(monoamineoxidase inhibitor),dopamine or serotonin synthesized during 25 min was measured by HPLC,employing electrochemical detection.Dopamine synthesis in synaptosomes prepared from young animals was markedly inhibited by addition of 5μM serotonin concentrations(30%)and increasing serotonin concentrations up to 50μM caused only a smaller additional inhibition.Dopamine synthesis in synaptosomes obtained from old rats was signifi cantly lower than that of youg animals and addition of serotonin concentrations up to 50μM had little effect on these preparations.In case of serotonin synthesis,exogenously added 5μM dopamine inhibited serotonin synthesis in the synaptosomes of both ages by about 40%,whereas with higher concentration of dopamine(10-50μM)the rate of inhibition was highly pronounced in old rats as compared to that of young animals.It is concluded that dopamine and serotonin interaction may be signifi cant,and that these should be considered in long-term treatments of Parkinson’s disease with L-DOPA.

关 键 词：aging nerve ENDING NEUROTRANSMITTER TYROSINE HYDROXYLASE TRYPTOPHAN HYDROXYLASE 

分 类 号：O62[理学—有机化学]