Gas chromatographic-mass spectrometric determination of dopamine in subregions of rat brain.
A quantitative gas chromatographic-mass spectrometric assay was developed for the determination of dopamine in subregions of rat brain. Five tissue punches weighing approximately 1.7 mg each were taken from the nucleus accumbens and four neostriatal regions differing in anterior-posterior level. The dopamine extracted from the tissue was treated with pentafluoropropionic anhydride (PFP) and quantitatively formed dopamine-(PFP)3. The derivatizing procedure took 15 min and the retention time for dopamine-(PFP)3 and its deuterated analogue [1,1,2,2-2H4]dopamine-(PFP)3) was 120 sec. Selective ion monitoring was utilized to monitor the gas chromatographic effluent. Ions were generated by electron impact ionization. The assay was able to measure concentrations of 1 nanogram dopamine per milligram protein. An anterior-posterior gradient of dopamine was observed in the striatum. This assay should be useful in studies examining the effects of experimental manipulations on dopamine content in relatively small areas of brain tissue.
D000818:Animals; D001923:Brain Chemistry; D004298:Dopamine / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D008297:Male; D051381:Rats; D014018:Tissue Distribution
D004298:Dopamine