Electrospray ionization mass spectrometry of low-molecular-mass S-nitroso compounds and their thiols.
Low-molecular-mass S-nitroso compounds (R-S-N=O) are potent vasodilators and inhibitors of platelet aggregation. This work describes the electrospray ionization mass spectrometric (ESI-MS) analysis of physiological and synthetic low-molecular-mass S-nitroso compounds and their thiols including S-nitrosoglutathione, S-nitrosocysteine, glutathione and cysteine. Mass spectra of the unlabeled and S-15N-labeled low-molecular-mass S-nitroso compounds investigated are characterized by abundant cations due to [M+H]+, [M+Na]+, [(M+H)-NO]+, [2 M+H]+, and [(2 M+H)-2NO]+. Mass spectra of low-molecular-mass thiols are characterized by abundant cations due to [M+H]+, [M+Na]+ and [2M+H]+. Using off-line electrospray ionization tandem mass spectrometry we unequivocally identified S-[15N]nitrosoglutathione in human red blood cells formed after their incubation with S-[15N]nitrosocysteine. These results suggest that ESI-MS in combination with an appropriate liquid chromatographic system should be a useful analytical approach for the on-line quantitative determination of low-molecular-mass S-nitroso compounds in biological fluids in the presence of their thiols and nitrite. Considerations were made about on-line ESI-MS and quantitative measurements.
Tsikas
D
D
Institute of Clinical Pharmacology, Hannover Medical School, and Lower Saxony Institute of Peptide Research, Germany. tsikas.dimitros@mh-hannover.de
Raida
M
M
Sandmann
J
J
Rossa
S
S
Forssmann
W G
WG
Frölich
J C
JC
D016477:Artifacts; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D008970:Molecular Weight; D009603:Nitroso Compounds / Q000032:analysis* / Q000097:blood; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000032:analysis* / Q000097:blood
D009603:Nitroso Compounds; D013438:Sulfhydryl Compounds