- Email: [email protected]
Reply to Dr. Michael J. Kelner
226
Letters to the Editors
type c o m p o u n d 5 that w o u l d be expected to o c c u r after reaction o f the herbicide with superoxide. While not definitive p r o o f that the reaction o f superoxide with thioureas is biologically i m p o r t a n t , it is plausible that the reaction occurs in vivo. Michael J. Kelner
University Hospital University o f California Medical Center 225 Dickinson Street San Diego, CA 92103, USA
REFERENCES
1. Lesnefsky, E. J. Reduction of infarct size by cell-permeable oxygen metabolite scavengers. Free Radic. Biol. Med. 12:429-446; 1992.
2. Fox, R. B. Prevention ofgranulocyte-mediated oxidant lung injury in rats by a hydroxyl scavenger, dimethylthiourea. J. Clin. Invest. 74:1456-1464; 1984. 3. Kelner, M. J.; Bagnell, R.; Welch, K. J. Thioureas react with superoxide radicals to yield a sulfhydryl compound. Explanation for protective effect against paraquat. J. Biol. Chem. 265:1306-131 l; 1990. 4. Bors, W,; Michel, C.; Saram, M. Determination of kinetic parameters of oxygen radicals by competition studies. CRC handbook of methodsfor oxygen radical research. Boca Raton, FL: CRC Press; 1985:181-187. 5. Griffiths, M. H.; Moss, J. A.; Rose, J. A.; Hathway, D. E. The comparative metabolism of 2,6,-dichlorothiobenzamide (Prefix) and 2,6-dichlorobenzonitrile in the dog and rat. Biochem. J. 98:770-781; 1966. 6. Babbs, C. F.; Griffin, D. W. Scatchard analysis of methane sulfinic acid production from dimethyl sulfoxide: A method to quantify hydroxyl radical formation in physiologic systems. Free Radic. Biol. Med. 6:493-503; 1989. 7. Paez, O. A.; Valdez, C, M.; June-Fe, T. Reactivity ofsuperoxide ion with thioamides in dimethyl sulfoxide. J. Organic Chem. 53:2166-2170; 1988.
REPLY TO DR. MICHAEL J. KELNER T o the Editors: It was a pleasure to review the c o m p l e t e study by Drs. Kelner, Bagnell, a n d Welch (reference 3 in the preceding letter), which rather convincingly d e m o n -
strates that D M T U does scavenge the superoxide anion. T h e authors also reconcile their findings with previous studies in the literature (reference 2). E d w a r d J. Lesnefsky
Division o f Cardiology Case Western Reserve University Cleveland, O H 44106, USA
Letters to the Editors
type c o m p o u n d 5 that w o u l d be expected to o c c u r after reaction o f the herbicide with superoxide. While not definitive p r o o f that the reaction o f superoxide with thioureas is biologically i m p o r t a n t , it is plausible that the reaction occurs in vivo. Michael J. Kelner
University Hospital University o f California Medical Center 225 Dickinson Street San Diego, CA 92103, USA
REFERENCES
1. Lesnefsky, E. J. Reduction of infarct size by cell-permeable oxygen metabolite scavengers. Free Radic. Biol. Med. 12:429-446; 1992.
2. Fox, R. B. Prevention ofgranulocyte-mediated oxidant lung injury in rats by a hydroxyl scavenger, dimethylthiourea. J. Clin. Invest. 74:1456-1464; 1984. 3. Kelner, M. J.; Bagnell, R.; Welch, K. J. Thioureas react with superoxide radicals to yield a sulfhydryl compound. Explanation for protective effect against paraquat. J. Biol. Chem. 265:1306-131 l; 1990. 4. Bors, W,; Michel, C.; Saram, M. Determination of kinetic parameters of oxygen radicals by competition studies. CRC handbook of methodsfor oxygen radical research. Boca Raton, FL: CRC Press; 1985:181-187. 5. Griffiths, M. H.; Moss, J. A.; Rose, J. A.; Hathway, D. E. The comparative metabolism of 2,6,-dichlorothiobenzamide (Prefix) and 2,6-dichlorobenzonitrile in the dog and rat. Biochem. J. 98:770-781; 1966. 6. Babbs, C. F.; Griffin, D. W. Scatchard analysis of methane sulfinic acid production from dimethyl sulfoxide: A method to quantify hydroxyl radical formation in physiologic systems. Free Radic. Biol. Med. 6:493-503; 1989. 7. Paez, O. A.; Valdez, C, M.; June-Fe, T. Reactivity ofsuperoxide ion with thioamides in dimethyl sulfoxide. J. Organic Chem. 53:2166-2170; 1988.
REPLY TO DR. MICHAEL J. KELNER T o the Editors: It was a pleasure to review the c o m p l e t e study by Drs. Kelner, Bagnell, a n d Welch (reference 3 in the preceding letter), which rather convincingly d e m o n -
strates that D M T U does scavenge the superoxide anion. T h e authors also reconcile their findings with previous studies in the literature (reference 2). E d w a r d J. Lesnefsky
Division o f Cardiology Case Western Reserve University Cleveland, O H 44106, USA