title: Determination of endothelium-derived nitrite/nitrate by gas chromatography/tandem mass spectrometry using (15N)NaNO2 as internal standard.
abstract: A sensitive gas chromatographic/tandem mass spectrometric method for the determination of nitrite and nitrate in endothelial cell column perfusates was developed. Nitrite/nitrate were converted in the presence of the internal standard (15N)NaNO2 to the corresponding 1-nitro-2,4,6-trimethoxybenzene (NTMB) derivatives which were subsequently analysed by gas chromatography/tandem mass spectrometry, monitoring m/z = 46 and m/z = 47, respectively. The good reproducibility, the wide linear range of the calibration curve from 25 ng ml-1 to 2500 ng ml-1 nitrite and the low detection limit of 200 pg NTMB allowed a sensitive and accurate quantification of nitrite/nitrate in perfusates of endothelial cell columns. Bradykinin had a stimulating effect on human and bovine endothelial cells and led to a threefold increase of nitrite/nitrate in endothelial cell column perfusates compared to those of unstimulated cells.
authors.affiliation: Department of Clinical Pharmacology, Hannover Medical School, Germany.
authors.forename: F M
authors.initials: FM
authors.lastname: Gutzki
authors.forename: D
authors.initials: D
authors.lastname: Tsikas
authors.forename: U
authors.initials: U
authors.lastname: Alheid
authors.forename: J C
authors.initials: JC
authors.lastname: Frölich
mesh_terms: D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D002417:Cattle; D004730:Endothelium, Vascular / Q000737:chemistry* / Q000166:cytology; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007202:Indicators and Reagents; D009566:Nitrates / Q000032:analysis*; D009573:Nitrites / Q000032:analysis*; D009578:Nitrobenzenes / Q000032:analysis; D012015:Reference Standards; D013268:Stimulation, Chemical
chemical_list: D007202:Indicators and Reagents; D009566:Nitrates; D009573:Nitrites; D009578:Nitrobenzenes; D001920:Bradykinin