title: Mass fragmentographic determination of 5-hydroxytryptamine and 5-hydroxyindole-3-acetic acid in brain tissue using deuterated internal standards.
abstract: A mass fragmentographic method for the determination of 5-hydroxytryptamine (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) in the same extract of rat brain tissue is decribed. Deuterium-labelled analogues were used as internal standards. 5-HT and 5-HIAA were separated by solvent extraction and pentafluoropropionyl derivatives were prepared for the mass fragmentographic analysis. Multiple ion analysis confirmed the identity of 5-HT and 5-HIAA in the rat brain. At the mass numbers used routinely for the determination of 5-HT and 5-HIAA in the rat brain. At the mass numbers used routinely for the determination of 5-HT and 5-HIAA, the experimental error was below 3% (calculated from mean values of 0.05 and 0.24 nmole, respectively). The recovery of the authentic compounds added to brain extracts was more than 95%. The levels of 5-HT and 5-HIAA in the rat brain were 2.95 +/- 0.16 and 0.64 +/- 0.18 nmole/g, respectively. More than 100 samples could be analyzed within 3 days. The presence of 5-hydroxytryptophol in rat brain was also investigated, but none could be detected either as a conjugate or as the free alcohol.
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D001923:Brain Chemistry; D003903:Deuterium; D010134:Fenclonine / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006897:Hydroxyindoleacetic Acid / Q000032:analysis* / Q000378:metabolism; D008297:Male; D008832:Microchemistry; D010293:Pargyline / Q000494:pharmacology; D011339:Probenecid / Q000494:pharmacology; D051381:Rats; D012110:Reserpine / Q000494:pharmacology; D012701:Serotonin / Q000032:analysis* / Q000378:metabolism; D014364:Tryptophan / Q000494:pharmacology
chemical_list: D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D012110:Reserpine; D014364:Tryptophan; D010293:Pargyline; D003903:Deuterium; D011339:Probenecid; D010134:Fenclonine