Direct proof of nitric oxide formation from a nitrovasodilator metabolised by erythrocytes.
When 15N-isosorbide dinitrate was injected into rats, the venous blood showed a 2-line hyperfine structure in the electron spin resonance (ESR) spectra of NO hemoglobin (HbNO), proving generation of 15N-NO. When human blood was mixed with 15N-isosorbide dinitrate anaerobically, ESR spectra showed initially 14N-HbNO, which was then overwhelmed with the increased 15N-HbNO. With deoxygenation of the blood of another 4 male donors without addition of isosorbide dinitrate, two showed 14N-HbNO, but others did not, suggesting varied amount of NO-precursers, nitrosothiols, in human blood. Neither N-ethylmaleimide nor S-hexylglutathione, a glutathione-S-transferase inhibitor, inhibited the formation of UbNO in the hemolysate mixed anaerobically with isosorbide dinitrite.
First Department of Physiology, Medical School, Osaka University, Japan.
H
H
Kosaka
S
S
Tanaka
T
T
Yoshii
E
E
Kumura
A
A
Seiyama
T
T
Shiga
D000328:Adult; D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D004912:Erythrocytes / Q000378:metabolism*; D006442:Glycated Hemoglobin / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007548:Isosorbide Dinitrate / Q000097:blood*; D008297:Male; D009569:Nitric Oxide / Q000032:analysis / Q000097:blood* / Q000378:metabolism*; D009587:Nitrogen Isotopes; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values
D006442:Glycated Hemoglobin; D007548:Isosorbide Dinitrate; D009569:Nitric Oxide; D009587:Nitrogen Isotopes; C058377:hemoglobin A, glycosylated-nitric oxide complex