title: Assay for tyrosine hydroxylase by high-performance liquid chromatography with fluorescence detection.
abstract: A sensitive assay method for tyrosine hydroxylase in rat brain and adrenal medulla by high-performance liquid chromatography with fluorescence detection is described. L-DOPA formed enzymatically from the substrate L-tyrosine and alpha-methyldopa (internal standard), after clean-up with small cartridges of an activated alumina and a cation exchanger, Toyopak IC-SP M, are converted into the corresponding fluorescent compounds by reaction with 1,2-diphenylethylenediamine. The derivatives are separated by reversed-phase chromatography on TSK gel ODS-120T. The detection limit for L-DOPA formed enzymatically is 2 pmol per assay tube.
mesh_terms: D000313:Adrenal Medulla / Q000201:enzymology; D000818:Animals; D001921:Brain / Q000201:enzymology; D001923:Brain Chemistry / Q000187:drug effects; D002374:Catalase / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D007501:Iron / Q000494:pharmacology; D007980:Levodopa / Q000032:analysis; D008297:Male; D010649:Phenylalanine / Q000032:analysis; D051381:Rats; D013050:Spectrometry, Fluorescence; D014443:Tyrosine / Q000032:analysis; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis*
chemical_list: D014443:Tyrosine; D007980:Levodopa; D010649:Phenylalanine; D007501:Iron; D002374:Catalase; D014446:Tyrosine 3-Monooxygenase