Free radical scavenging drugs, assessed by ESR studies: influence of hemoglobin.
To monitor free radical scavenging properties of drugs, the 'stable' radical 2,2,6,6-tetramethylpiperidino-1-oxyl (TEMPO) was used. The sydnonimine molsidomine (SIN-1) effectively reduced the ESR signal whereas the nitrate isosorbidemononitrate (ISMN) did not. Thiol reagents like 2-mercaptopropionylglycine (MPG) or glutathione (GSH) only were effective in the presence of Fe2+ or Fe3+. Protein-bound iron in hemoglobin proved about four times more effective in reducing ESR signal height by thiols. It is suggested that the decrease in thiol content adds to the lack in protein bound iron of hemoglobin to induce the burst of free radicals in hypoxia (ischemia) and reperfusion.
Lammel
B
B
Gustav-Embden-Zentrum der Biologischen Chemie, Universität Frankfurt, FRG.
Pilz
S
S
Freisleben
H J
HJ
Schraven
E
E
Zimmer
G
G
D003497:Cyclic N-Oxides / Q000037:antagonists & inhibitors; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals; D005978:Glutathione / Q000494:pharmacology; D006454:Hemoglobins / Q000502:physiology*; D008981:Molsidomine / Q000494:pharmacology; D011500:Protein Synthesis Inhibitors / Q000037:antagonists & inhibitors; D013113:Spin Labels; D008625:Tiopronin / Q000494:pharmacology
D003497:Cyclic N-Oxides; D005609:Free Radicals; D006454:Hemoglobins; D011500:Protein Synthesis Inhibitors; D013113:Spin Labels; D008625:Tiopronin; D008981:Molsidomine; D005978:Glutathione; C001803:tempol