Mori H, Arai T, Mori K, Tsutsui H, Makino K
Department of Anesthesia, Kyoto University Hospital, Japan.
Biochem Mol Biol Int. 1994 Mar;32(3):523-9.
To determine whether hydroxyl radicals (.OH) are generated in the hypoxanthine (HPX)-xanthine oxidase (XOD) reaction, we examined the electron paramagnetic resonance (EPR) spectra of the spin adducts formed. In the EPR study, we used 3,3,5,5-tetramethyl-1-pyrroline-N-oxide (M4PO) as a spin trap, sodium formate (HCOONa) as a .OH scavenger, and oxygen-17 gas as an oxygen source. In the HPX-XOD reaction, both M4PO-OOH and M4PO-OH were observed in the reaction products. The formation of M4PO-OH was independently inhibited by HCOONa resulting in the formation of M4PO-CO2- and in no effects on the formation of M4PO-OOH. With oxygen-17 gas as an oxygen source in the HPX-XOD reaction, both M4PO-17OOH and M4PO-17OH were observed in the reaction products. These results indicate that M4PO-OH is not produced by decomposition of M4PO-OOH and .OH is actually generated during the HPX-XOD reaction.
为了确定次黄嘌呤（HPX）-黄嘌呤氧化酶（XOD）反应中是否会生成羟基自由基（·OH），我们检测了所形成的自旋加合物的电子顺磁共振（EPR）光谱。在EPR研究中，我们使用3,3,5,5-四甲基-1-吡咯啉-N-氧化物（M4PO）作为自旋捕捉剂，甲酸钠（HCOONa）作为·OH清除剂，以及17O2气体作为氧源。在HPX-XOD反应中，在反应产物中观察到了M4PO-OOH和M4PO-OH。M4PO-OH的形成受到HCOONa的独立抑制，导致形成M4PO-CO2-，且对M4PO-OOH的形成没有影响。在HPX-XOD反应中以17O2气体作为氧源时，在反应产物中观察到了M4PO-17OOH和M4PO-17OH。这些结果表明，M4PO-OH不是由M4PO-OOH分解产生的，并且在HPX-XOD反应过程中确实会生成·OH。
