Simultaneous measurement of adenosine, dopamine, acetylcholine and 5-hydroxytryptamine in cerebral mice microdialysis samples by LC-ESI-MS/MS.

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) method has been developed for the simultaneous measurement of adenosine (ADE), dopamine (DA), acetylcholine (ACh) and 5-hydroxytryptamine (5-HT) in mouse brain microdialysates. High method sensitivity (LLOQ of 0.05nM) was achieved by optimization of chromatographic and mass spectrometric parameters. The method was fully validated for its sensitivity, selectivity, matrix effect and stability. The LC-MS/MS method was successfully applied to evaluate the effect of the systemic administration of cocaine or amphetamine on the extracellular levels of ADE, DA, ACh and 5-HT in the mouse nucleus accumbens by microdialysis.