活性氧对血红蛋白损伤机理的研究

Mechanism of injury by active oxygen radical to hemoglobin

研究了超氧负离子（Ｏ－２）和过氧化氢（Ｈ２Ｏ２）对血红蛋白（Ｈｂ）的损伤作用。结果表明二者对Ｈｂ的损伤主要集中在血红素辅基部分，但二者损伤途径不同，Ｏ－２是通过电荷中和破坏了辅基与其周围氨基酸残基之间的静电相互作用，从而使辅基完整地脱落；而Ｈ２Ｏ２则是通过Ｆｅｎｔｏｎ反应与血红素辅基中心的Ｆｅ２＋反应产生羟自由基（ＯＨ），ＯＨ在短距离内定点损伤卟啉环结构。

The injury effects of O -· 2 and H 2O 2 on the hemoglobin were investigated.The results showed that the metal prosthetic group was injured by O -· 2 and H 2O 2,but the mechanism of O -· 2 and H 2O 2 effects was different.Through the charge neutralization O -· 2 destroying the static electrical interactions between prosthethic group and amino acid residues,it thereby caused prosthetic group dropped.H 2O 2 had Fenton reaction with Fe 2+ in prosthetic group,hence produced ·OH.It can destroy the porphyrin structure at fixed point in short distance,so the prosthetic group was destroyed and non reversible.