Key points are not available for this paper at this time.
Peroxynitrite (ONOO−) has been shown in studies on vascular relaxation and guanylate cyclase activation to react with glutathione (GSH), generating an intermediate product that promotes a time-dependent production of nitric oxide (NO). In this study, reactions of ONOO− with GSH produced a new substance, which was characterized by liquid chromatography, ultraviolet spectroscopy, and electrospray tandem mass spectrometry. The mass spectrometric data provided evidence that the product of this reaction was S-nitroglutathione (GSNO2) and that S-nitrosoglutathione (GSNO) was not a detectable product of this reaction. Further evidence was obtained by comparison of the spectral and chromatographic properties with synthetic standards prepared by reaction of GSH with nitrosonium or nitronium borofluorates. Both the synthetic and ONOO−/GSH-derived GSNO2 generated a protonated ion, GSNO2H+, at m/z 353, which was unusually resistant to decomposition under collision activation, and no fragmentation was observed at collision energy of 25 eV. In contrast, an ion at m/z 337 (GSNOH+), generated from the synthetic GSNO, readily fragmented with the abundant loss of NO at 9 eV. Reactions of ONOO− with GSH resulted in the generation of NO, which was detected by the head space/NO-chemiluminescence analyzer method. The generation of NO was inhibited by the presence of glucose and/or CO2 in the buffers employed. Synthetic GSNO2 spontaneously generated NO in a manner that was not significantly altered by glucose or CO2. Thus, ONOO− reacts with GSH to form GSNO2, and GSNO2 decomposes in a manner that generates NO. Peroxynitrite (ONOO−) has been shown in studies on vascular relaxation and guanylate cyclase activation to react with glutathione (GSH), generating an intermediate product that promotes a time-dependent production of nitric oxide (NO). In this study, reactions of ONOO− with GSH produced a new substance, which was characterized by liquid chromatography, ultraviolet spectroscopy, and electrospray tandem mass spectrometry. The mass spectrometric data provided evidence that the product of this reaction was S-nitroglutathione (GSNO2) and that S-nitrosoglutathione (GSNO) was not a detectable product of this reaction. Further evidence was obtained by comparison of the spectral and chromatographic properties with synthetic standards prepared by reaction of GSH with nitrosonium or nitronium borofluorates. Both the synthetic and ONOO−/GSH-derived GSNO2 generated a protonated ion, GSNO2H+, at m/z 353, which was unusually resistant to decomposition under collision activation, and no fragmentation was observed at collision energy of 25 eV. In contrast, an ion at m/z 337 (GSNOH+), generated from the synthetic GSNO, readily fragmented with the abundant loss of NO at 9 eV. Reactions of ONOO− with GSH resulted in the generation of NO, which was detected by the head space/NO-chemiluminescence analyzer method. The generation of NO was inhibited by the presence of glucose and/or CO2 in the buffers employed. Synthetic GSNO2 spontaneously generated NO in a manner that was not significantly altered by glucose or CO2. Thus, ONOO− reacts with GSH to form GSNO2, and GSNO2 decomposes in a manner that generates NO. peroxynitrite glutathione nitric oxide S-nitroglutathione S-nitrosoglutathione high performance liquid chromatography reverse-phase electrospray ionization tandem mass spectrometry. Exposure of vascular tissue to peroxynitrite (ONOO−)1 results in a prolonged relaxation (1Liu S. Beckman J.S. Ku D.D. J. Pharmacol. Exp. Ther. 1994; 268: 1114-1121PubMed Google Scholar) that appears to be mediated through a glutathione (GSH)-dependent regeneration of NO (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). Peroxynitrite has also been observed to stimulate guanylate cyclase activity in a thiol-dependent manner in vascular endothelial and smooth muscle preparations (3Mayer B. Schrammel A. Klatt P. Koesling D. Schmidt K. J. Biol. Chem. 1995; 270: 17355-17360Abstract Full Text Full Text PDF PubMed Scopus (186) Google Scholar, 4Tarpey M.M. Beckman J.S. Ischiropoulos H. Gore J.Z. Brock T.A. FEBS Lett. 1995; 364: 314-318Crossref PubMed Scopus (100) Google Scholar). Whereas the reaction of ONOO− with GSH has been reported to form small amounts of S-nitroso-GSH (GSNO) (3Mayer B. Schrammel A. Klatt P. Koesling D. Schmidt K. J. Biol. Chem. 1995; 270: 17355-17360Abstract Full Text Full Text PDF PubMed Scopus (186) Google Scholar, 5Moro M.A. Darley-Usmar V.M. Goodwin D.A. Read N.G. Zamora-Pino R. Feelisch M. Radomski M.W. Moncada S. Proc. Natl. Acad. Sci. U. S. A. 1994; 91: 6702-6706Crossref PubMed Scopus (336) Google Scholar), our previous studies detected a different product of this reaction, which was isolated and demonstrated to possess potent vascular relaxant activity (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). Examination of the reaction of nitrogen dioxide (NO2) with GSH detected the formation of what appears to be the same product as that observed in the reaction with ONOO− (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar). Because the biologically active metabolite of these reactions co-migrated on HPLC with a the product of a reaction between nitrosonium borofluorate (NO2BF4) and GSH, the vascular relaxant detected was suggested to be a nitrated product of GSH (GSNO2) (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar). Thus, additional studies are needed to identify the biologically active substances derived from the reaction of GSH with ONOO−.Peroxynitrite is also known to undergo additional reactions in the presence of physiological buffered systems and GSH. One of the first observed actions of ONOO− on thiols was that it caused oxidation reactions, and an analysis of products of these reactions resulted in a hypothesis that nitrated thiols were a key unstable intermediate formed during these reactions (7Radi R. Beckman J.S. Bush K.M. Freeman B.A. J. Biol. Chem. 1991; 266: 4244-4250Abstract Full Text PDF PubMed Google Scholar, 8Zhang H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar). Recent studies have also provided evidence that thiol radicals seem to be one of the major initial products of the reaction of ONOO− with thiols (9Karoui H. Hansert B. Sand P.J. Tordo P. Bohle D.S. Kalyanaraman B. Nitric Oxide Biol. Med. 1997; 1: 346-358Crossref PubMed Scopus (7) Google Scholar,10Quijano C. Alvarez B. Gatti R.M. Augusto O. Radi R. Biochem. J. 1997; 322: 167-173Crossref PubMed Scopus (232) Google Scholar). Peroxynitrite appears to react with glucose and other hydroxylated compounds to produce relatively stable products that cause tissue- or thiol-dependent generation of NO and a prolonged relaxation of vascular tissue (11Moro M.A. Darley-Usmar V.M. Lizasoain I. Su Y. Knowles R.G. Radomski M.W. Moncada S. Br. J. Pharmacol. 1995; 116: 1999-2004Crossref PubMed Scopus (183) Google Scholar, 12White C.R. Moellering D. Patel R.P. Kirk M. Barnes S. Darley-Usmar V.M. Biochem. J. 1997; 328: 517-524Crossref PubMed Scopus (31) Google Scholar). However, the vasoactive products formed from reactions with glucose seem to be significant only at very elevated levels of ONOO− (13Dowell F.J. Martin W. Eur. J. Pharmacol. 1997; 338: 43-53Crossref PubMed Scopus (33) Google Scholar). Peroxynitrite also reacts with CO2/bicarbonate to an intermediate that is a potent R.M. Squadrito G.L. Pryor W.A. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, A. Freeman B.A. M. Radi R. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, W.A. Lemercier J.N. H. Uppu R.M. Squadrito G.L. Biol. Med. 1997; PubMed Scopus Google Scholar, Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar). Thus, ONOO− with additional of and buffers to form biologically active The of this was to the reaction of ONOO− with GSH generates to of the formation in the generation of NO from results of the evidence our (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar) that GSNO2 is a stable product of the reaction of ONOO− with GSH. have observed that a product of the reaction between ONOO− and GSH has the properties of a that NO, and a product of this reaction was isolated and shown to cause what to be a relaxation (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). In the study, GSNO2 was and to spontaneously NO was The data obtained also that nitrated of glucose or dioxide not seem to be to the generation of NO from ONOO− under the Thus, GSNO2 be a key in the generation of NO from ONOO− in the presence of GSH of a key product that results from the reaction of GSH with ONOO− detected an ion with an m/z of that a mass with that of synthetic GSNO2 produced from the reaction of GSH with The ONOO−/GSH-derived product was different from synthetic GSNO, which was not a detectable product of this reaction. activation of GSNO2 derived from with 25 not produce the ion with an m/z at 337 of readily fragmented at 9 eV. the of the of protonated form of GSNO2 is not reported J. Chem. 1995; Google Scholar) on thiol that have a very to Thus, it is that between these a of to the fragmentation of The of GSNO2 in the electrospray be also by the of to GSNO2, a that is to in at In a buffered other as and to the of NO from Further studies are needed to the of GSNO2 in has been reported that detectable amounts of NO K. J. C. Chem. 1996; Scopus Google Scholar). The of this decomposition is relatively and in the of at K. J. C. Chem. 1996; Scopus Google Scholar). a of it was suggested that the of thiol to by the decomposition of was a of NO generation K. J. C. Chem. 1996; Scopus Google Scholar, J. Chem. 1995; Google Scholar). was also observed that NO through a that was inhibited by and this of glutathione was in the with reaction of thiols with in the formation of and was suggested as an the observed formation of NO K. J. C. Chem. 1996; Scopus Google Scholar). Thus, the of NO from GSNO2 has with previous of NO from it has been suggested that nitrated thiols are very unstable (7Radi R. Beckman J.S. Bush K.M. Freeman B.A. J. Biol. Chem. 1991; 266: 4244-4250Abstract Full Text PDF PubMed Google Scholar, 8Zhang H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar), the observed NO form GSNO2 a prolonged that these substances be stable were to Because the of a of the is not to in J. Chem. 1995; Google Scholar), a that to be is NO from or of the formed (GSNO2) that and buffers the of NO generation from ONOO− in the presence of GSH and the of an of these on the of NO from GSNO2 are with previous on the of Whereas ONOO− reacts with CO2/bicarbonate to form an intermediate that the of of the reactions caused by ONOO− R.M. Squadrito G.L. Pryor W.A. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, A. Freeman B.A. M. Radi R. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, W.A. Lemercier J.N. H. Uppu R.M. Squadrito G.L. Biol. Med. 1997; PubMed Scopus Google Scholar), data in the that this not the formation of the key which appears to be ONOO− reacts with glucose other hydroxylated to produce (11Moro M.A. Darley-Usmar V.M. Lizasoain I. Su Y. Knowles R.G. Radomski M.W. Moncada S. Br. J. Pharmacol. 1995; 116: 1999-2004Crossref PubMed Scopus (183) Google Scholar, 12White C.R. Moellering D. Patel R.P. Kirk M. Barnes S. Darley-Usmar V.M. Biochem. J. 1997; 328: 517-524Crossref PubMed Scopus (31) Google Scholar), it appears that the products that form have of a to NO in the presence of GSH the that form in the of Thus, the in the to be GSNO2 appears to from a reaction of GSH with ONOO− that is not by glucose or Because thiol radicals and nitrogen dioxide seem to be key initial products of the of ONOO− and thiols H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar, H. Hansert B. Sand P.J. Tordo P. Bohle D.S. Kalyanaraman B. Nitric Oxide Biol. Med. 1997; 1: 346-358Crossref PubMed Scopus (7) Google Scholar, C. Alvarez B. Gatti R.M. Augusto O. Radi R. Biochem. J. 1997; 322: 167-173Crossref PubMed Scopus (232) Google Scholar), thiol is a of a reaction between these in the on the reaction of ONOO− with GSH are with GSNO2 a key intermediate that in the generation of NO. studies on C.A. Kaminski P.M. Wolin M.S. Nitric Oxide Biol. Med. 1997; 1: PubMed Scopus (7) Google Scholar) and C.A. Kaminski P.M. Wolin M.S. Am. J. Physiol. 1997; Google Scholar) have provided evidence that of NO as as cause a of that a prolonged relaxation of these vascular as a of a thiol-dependent that in the regeneration of NO. In to be a key metabolite of J. Biol. Chem. Full Text PDF PubMed Google Scholar). GSNO2 be an biologically active metabolite of NO oxidation and Exposure of vascular tissue to peroxynitrite (ONOO−)1 results in a prolonged relaxation (1Liu S. Beckman J.S. Ku D.D. J. Pharmacol. Exp. Ther. 1994; 268: 1114-1121PubMed Google Scholar) that appears to be mediated through a glutathione (GSH)-dependent regeneration of NO (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). Peroxynitrite has also been observed to stimulate guanylate cyclase activity in a thiol-dependent manner in vascular endothelial and smooth muscle preparations (3Mayer B. Schrammel A. Klatt P. Koesling D. Schmidt K. J. Biol. Chem. 1995; 270: 17355-17360Abstract Full Text Full Text PDF PubMed Scopus (186) Google Scholar, 4Tarpey M.M. Beckman J.S. Ischiropoulos H. Gore J.Z. Brock T.A. FEBS Lett. 1995; 364: 314-318Crossref PubMed Scopus (100) Google Scholar). Whereas the reaction of ONOO− with GSH has been reported to form small amounts of S-nitroso-GSH (GSNO) (3Mayer B. Schrammel A. Klatt P. Koesling D. Schmidt K. J. Biol. Chem. 1995; 270: 17355-17360Abstract Full Text Full Text PDF PubMed Scopus (186) Google Scholar, 5Moro M.A. Darley-Usmar V.M. Goodwin D.A. Read N.G. Zamora-Pino R. Feelisch M. Radomski M.W. Moncada S. Proc. Natl. Acad. Sci. U. S. A. 1994; 91: 6702-6706Crossref PubMed Scopus (336) Google Scholar), our previous studies detected a different product of this reaction, which was isolated and demonstrated to possess potent vascular relaxant activity (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). Examination of the reaction of nitrogen dioxide (NO2) with GSH detected the formation of what appears to be the same product as that observed in the reaction with ONOO− (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar). Because the biologically active metabolite of these reactions co-migrated on HPLC with a the product of a reaction between nitrosonium borofluorate (NO2BF4) and GSH, the vascular relaxant detected was suggested to be a nitrated product of GSH (GSNO2) (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar). Thus, additional studies are needed to identify the biologically active substances derived from the reaction of GSH with Peroxynitrite is also known to undergo additional reactions in the presence of physiological buffered systems and GSH. One of the first observed actions of ONOO− on thiols was that it caused oxidation reactions, and an analysis of products of these reactions resulted in a hypothesis that nitrated thiols were a key unstable intermediate formed during these reactions (7Radi R. Beckman J.S. Bush K.M. Freeman B.A. J. Biol. Chem. 1991; 266: 4244-4250Abstract Full Text PDF PubMed Google Scholar, 8Zhang H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar). Recent studies have also provided evidence that thiol radicals seem to be one of the major initial products of the reaction of ONOO− with thiols (9Karoui H. Hansert B. Sand P.J. Tordo P. Bohle D.S. Kalyanaraman B. Nitric Oxide Biol. Med. 1997; 1: 346-358Crossref PubMed Scopus (7) Google Scholar,10Quijano C. Alvarez B. Gatti R.M. Augusto O. Radi R. Biochem. J. 1997; 322: 167-173Crossref PubMed Scopus (232) Google Scholar). Peroxynitrite appears to react with glucose and other hydroxylated compounds to produce relatively stable products that cause tissue- or thiol-dependent generation of NO and a prolonged relaxation of vascular tissue (11Moro M.A. Darley-Usmar V.M. Lizasoain I. Su Y. Knowles R.G. Radomski M.W. Moncada S. Br. J. Pharmacol. 1995; 116: 1999-2004Crossref PubMed Scopus (183) Google Scholar, 12White C.R. Moellering D. Patel R.P. Kirk M. Barnes S. Darley-Usmar V.M. Biochem. J. 1997; 328: 517-524Crossref PubMed Scopus (31) Google Scholar). However, the vasoactive products formed from reactions with glucose seem to be significant only at very elevated levels of ONOO− (13Dowell F.J. Martin W. Eur. J. Pharmacol. 1997; 338: 43-53Crossref PubMed Scopus (33) Google Scholar). Peroxynitrite also reacts with CO2/bicarbonate to an intermediate that is a potent R.M. Squadrito G.L. Pryor W.A. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, A. Freeman B.A. M. Radi R. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, W.A. Lemercier J.N. H. Uppu R.M. Squadrito G.L. Biol. Med. 1997; PubMed Scopus Google Scholar, Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar). Thus, ONOO− with additional of and buffers to form biologically active The of this was to the reaction of ONOO− with GSH generates to of the formation in the generation of NO from results of the evidence our (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar) that GSNO2 is a stable product of the reaction of ONOO− with GSH. have observed that a product of the reaction between ONOO− and GSH has the properties of a that NO, and a product of this reaction was isolated and shown to cause what to be a relaxation (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). In the study, GSNO2 was and to spontaneously NO was The data obtained also that nitrated of glucose or dioxide not seem to be to the generation of NO from ONOO− under the Thus, GSNO2 be a key in the generation of NO from ONOO− in the presence of GSH of a key product that results from the reaction of GSH with ONOO− detected an ion with an m/z of that a mass with that of synthetic GSNO2 produced from the reaction of GSH with The ONOO−/GSH-derived product was different from synthetic GSNO, which was not a detectable product of this reaction. activation of GSNO2 derived from with 25 not produce the ion with an m/z at 337 of readily fragmented at 9 eV. the of the of protonated form of GSNO2 is not reported J. Chem. 1995; Google Scholar) on thiol that have a very to Thus, it is that between these a of to the fragmentation of The of GSNO2 in the electrospray be also by the of to GSNO2, a that is to in at In a buffered other as and to the of NO from Further studies are needed to the of GSNO2 in has been reported that detectable amounts of NO K. J. C. Chem. 1996; Scopus Google Scholar). The of this decomposition is relatively and in the of at K. J. C. Chem. 1996; Scopus Google Scholar). a of it was suggested that the of thiol to by the decomposition of was a of NO generation K. J. C. Chem. 1996; Scopus Google Scholar, J. Chem. 1995; Google Scholar). was also observed that NO through a that was inhibited by and this of glutathione was in the with reaction of thiols with in the formation of and was suggested as an the observed formation of NO K. J. C. Chem. 1996; Scopus Google Scholar). Thus, the of NO from GSNO2 has with previous of NO from it has been suggested that nitrated thiols are very unstable (7Radi R. Beckman J.S. Bush K.M. Freeman B.A. J. Biol. Chem. 1991; 266: 4244-4250Abstract Full Text PDF PubMed Google Scholar, 8Zhang H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar), the observed NO form GSNO2 a prolonged that these substances be stable were to Because the of a of the is not to in J. Chem. 1995; Google Scholar), a that to be is NO from or of the formed (GSNO2) that and buffers the of NO generation from ONOO− in the presence of GSH and the of an of these on the of NO from GSNO2 are with previous on the of Whereas ONOO− reacts with CO2/bicarbonate to form an intermediate that the of of the reactions caused by ONOO− R.M. Squadrito G.L. Pryor W.A. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, A. Freeman B.A. M. Radi R. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, W.A. Lemercier J.N. H. Uppu R.M. Squadrito G.L. Biol. Med. 1997; PubMed Scopus Google Scholar), data in the that this not the formation of the key which appears to be ONOO− reacts with glucose other hydroxylated to produce (11Moro M.A. Darley-Usmar V.M. Lizasoain I. Su Y. Knowles R.G. Radomski M.W. Moncada S. Br. J. Pharmacol. 1995; 116: 1999-2004Crossref PubMed Scopus (183) Google Scholar, 12White C.R. Moellering D. Patel R.P. Kirk M. Barnes S. Darley-Usmar V.M. Biochem. J. 1997; 328: 517-524Crossref PubMed Scopus (31) Google Scholar), it appears that the products that form have of a to NO in the presence of GSH the that form in the of Thus, the in the to be GSNO2 appears to from a reaction of GSH with ONOO− that is not by glucose or Because thiol radicals and nitrogen dioxide seem to be key initial products of the of ONOO− and thiols H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar, H. Hansert B. Sand P.J. Tordo P. Bohle D.S. Kalyanaraman B. Nitric Oxide Biol. Med. 1997; 1: 346-358Crossref PubMed Scopus (7) Google Scholar, C. Alvarez B. Gatti R.M. Augusto O. Radi R. Biochem. J. 1997; 322: 167-173Crossref PubMed Scopus (232) Google Scholar), thiol is a of a reaction between these in the on the reaction of ONOO− with GSH are with GSNO2 a key intermediate that in the generation of NO. studies on C.A. Kaminski P.M. Wolin M.S. Nitric Oxide Biol. Med. 1997; 1: PubMed Scopus (7) Google Scholar) and C.A. Kaminski P.M. Wolin M.S. Am. J. Physiol. 1997; Google Scholar) have provided evidence that of NO as as cause a of that a prolonged relaxation of these vascular as a of a thiol-dependent that in the regeneration of NO. In to be a key metabolite of J. Biol. Chem. Full Text PDF PubMed Google Scholar). GSNO2 be an biologically active metabolite of NO oxidation and The results of the evidence our (6Davidson C.A. Kaminski P.M. Wu M. Wolin M.S. Am. J. Physiol. 1996; 270: H1038-H1043PubMed Google Scholar) that GSNO2 is a stable product of the reaction of ONOO− with GSH. have observed that a product of the reaction between ONOO− and GSH has the properties of a that NO, and a product of this reaction was isolated and shown to cause what to be a relaxation (2Wu M. Pritchard Jr., K.A. Kaminski P.M. Fayngersh R.P. Hintze T.H. Wolin M.S. Am. J. Physiol. 1994; 266: H2108-H2113PubMed Google Scholar). In the study, GSNO2 was and to spontaneously NO was The data obtained also that nitrated of glucose or dioxide not seem to be to the generation of NO from ONOO− under the Thus, GSNO2 be a key in the generation of NO from ONOO− in the presence of GSH of a key product that results from the reaction of GSH with ONOO− detected an ion with an m/z of that a mass with that of synthetic GSNO2 produced from the reaction of GSH with The ONOO−/GSH-derived product was different from synthetic GSNO, which was not a detectable product of this reaction. activation of GSNO2 derived from with 25 not produce the ion with an m/z at 337 of readily fragmented at 9 eV. the of the of protonated form of GSNO2 is not reported J. Chem. 1995; Google Scholar) on thiol that have a very to Thus, it is that between these a of to the fragmentation of The of GSNO2 in the electrospray be also by the of to GSNO2, a that is to in at In a buffered other as and to the of NO from Further studies are needed to the of GSNO2 in has been reported that detectable amounts of NO K. J. C. Chem. 1996; Scopus Google Scholar). The of this decomposition is relatively and in the of at K. J. C. Chem. 1996; Scopus Google Scholar). a of it was suggested that the of thiol to by the decomposition of was a of NO generation K. J. C. Chem. 1996; Scopus Google Scholar, J. Chem. 1995; Google Scholar). was also observed that NO through a that was inhibited by and this of glutathione was in the with reaction of thiols with in the formation of and was suggested as an the observed formation of NO K. J. C. Chem. 1996; Scopus Google Scholar). Thus, the of NO from GSNO2 has with previous of NO from it has been suggested that nitrated thiols are very unstable (7Radi R. Beckman J.S. Bush K.M. Freeman B.A. J. Biol. Chem. 1991; 266: 4244-4250Abstract Full Text PDF PubMed Google Scholar, 8Zhang H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar), the observed NO form GSNO2 a prolonged that these substances be stable were to Because the of a of the is not to in J. Chem. 1995; Google Scholar), a that to be is NO from or of the formed (GSNO2) The that and buffers the of NO generation from ONOO− in the presence of GSH and the of an of these on the of NO from GSNO2 are with previous on the of Whereas ONOO− reacts with CO2/bicarbonate to form an intermediate that the of of the reactions caused by ONOO− R.M. Squadrito G.L. Pryor W.A. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, A. Freeman B.A. M. Radi R. Arch. Biochem. Biophys. 1996; PubMed Scopus Google Scholar, W.A. Lemercier J.N. H. Uppu R.M. Squadrito G.L. Biol. Med. 1997; PubMed Scopus Google Scholar), data in the that this not the formation of the key which appears to be ONOO− reacts with glucose other hydroxylated to produce (11Moro M.A. Darley-Usmar V.M. Lizasoain I. Su Y. Knowles R.G. Radomski M.W. Moncada S. Br. J. Pharmacol. 1995; 116: 1999-2004Crossref PubMed Scopus (183) Google Scholar, 12White C.R. Moellering D. Patel R.P. Kirk M. Barnes S. Darley-Usmar V.M. Biochem. J. 1997; 328: 517-524Crossref PubMed Scopus (31) Google Scholar), it appears that the products that form have of a to NO in the presence of GSH the that form in the of Thus, the in the to be GSNO2 appears to from a reaction of GSH with ONOO− that is not by glucose or Because thiol radicals and nitrogen dioxide seem to be key initial products of the of ONOO− and thiols H. Squadrito G.L. Uppu R.M. Lemercier J.N. Cueto R. Pryor W.A. Arch. Biochem. Biophys. 1997; 339: 183-189Crossref PubMed Scopus (73) Google Scholar, H. Hansert B. Sand P.J. Tordo P. Bohle D.S. Kalyanaraman B. Nitric Oxide Biol. Med. 1997; 1: 346-358Crossref PubMed Scopus (7) Google Scholar, C. Alvarez B. Gatti R.M. Augusto O. Radi R. Biochem. J. 1997; 322: 167-173Crossref PubMed Scopus (232) Google Scholar), thiol is a of a reaction between these in the on the reaction of ONOO− with GSH are with GSNO2 a key intermediate that in the generation of NO. studies on C.A. Kaminski P.M. Wolin M.S. Nitric Oxide Biol. Med. 1997; 1: PubMed Scopus (7) Google Scholar) and C.A. Kaminski P.M. Wolin M.S. Am. J. Physiol. 1997; Google Scholar) have provided evidence that of NO as as cause a of that a prolonged relaxation of these vascular as a of a thiol-dependent that in the regeneration of NO. In to be a key metabolite of J. Biol. Chem. Full Text PDF PubMed Google Scholar). GSNO2 be an biologically active metabolite of NO oxidation and from the of by mass spectrometry.
Balazy et al. (Sun,) studied this question.