Effect of ferrous iron on the generation of hydroxyl free radicals by liver microdialysis perfusion of salicylate.
1. We applied in vivo microdialysis technique to examine the effect of Fe2+, Fe3+, Cu2+ and Zn2+ on free radical-generation of rat liver. The hydroxyl free radical (.OH) reacts with salicylate and generates 2,3- and 2,5-dihydroxybenzoic acid (DHBA) which can be measured electrochemically in picomole quantity by HPLC-EC procedure. 2. The relative rates of recovery of 2,3- and 2,5-DHBA at 1 microliter/min in vitro were an average of 10.1 +/- 0.8% and 10.5 +/- 9%, respectively. 3. When the metal ion infused through the dialysis probe, Fe2+ but not Fe3+, Cu2+ and Zn2+ caused an increase in the formation of DHBA of rat liver. 4. After the Ringer solution containing 10 mumole/kg was injected into the penile vein, the levels of 2,3- and 2,5-DHBA were increased about 60% and 40%, respectively. 5. These results indicate that non-enzymatic oxidation in the extracellular fluid may play a key role in Fe2+ generation of -OH in liver. Free radical formation processes may contribute to in vivo free radical formation induced by Fe2+.
Obata
T
T
Department of Pharmacology, Oita Medical University, Japan.
Hosokawa
H
H
Yamanaka
Y
Y
D000818:Animals; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D005296:Ferrous Compounds / Q000494:pharmacology*; D005609:Free Radicals / Q000378:metabolism; D005841:Gentisates; D062385:Hydroxybenzoates / Q000378:metabolism; D006900:Hydroxylation; D007502:Iron Chelating Agents; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008670:Metals / Q000494:pharmacology; D017551:Microdialysis; D010477:Perfusion; D051381:Rats; D017208:Rats, Wistar; D012459:Salicylates / Q000378:metabolism*; D020156:Salicylic Acid
D005296:Ferrous Compounds; D005609:Free Radicals; D005841:Gentisates; D062385:Hydroxybenzoates; D007502:Iron Chelating Agents; D008670:Metals; D012459:Salicylates; C009135:2,3-dihydroxybenzoic acid; D020156:Salicylic Acid; C010925:2,5-dihydroxybenzoic acid