ABSTRACT
AIM To establish the method of continuous measuring extracellular Acetylcholine and Choline levels in[FQ(10*2。46,X-WZ]-striatum of freely moving awake rats. METHODS The microdialysis and high performance liquid chromatography(HPLC)-post column Immobilized enzyme reactor(IMER)-electrochemical detection(ED) were used to continuously measure extracellular acetylcholine and choline levels in striatum of freely moving awake rats. RESULTS Extracellular acetylcholine and choline levels were higher at the beginning of perfusion, then decreased gradually. The ACh concentration reached a stable level after 240 min while the Ch continuously decreased in the whole perfusion period of 450 min. The detection limit for ACh and Ch, at a S/N ratio of three, was found to be 150 fmol per injection. In the range of 0.125～1.0 ?mol?L -1 , the relation between the amounts and the peak amplitude was linear. CONCLUSION HPLC-IMER-ED is a sensitive and stable method to measure the ACh and Ch. Coupled with microdialysis, it can been successfully used for monitoring the extracellular ACh and Ch levels of freely moving awake rats. -