Hemoglobin catabolism. II. The protection of hemoglobin from oxidative breakdown in the intact erythrocyte.
Hemoglobin catabolism. II. The protection of hemoglobin from oxidative breakdown in the intact erythrocyte.
复制标题
血红蛋白分解代谢。
DOI：
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发表时间：
1958
影响因子：
4.8
通讯作者：
H. Randall
中科院分区：
文献类型：
--
作者：
G. C. Mills;H. Randall
只有当反应的产物GSSG不断还原为GSH时，这种保护系统才有持久的效果。先前研究人员的工作表明，红细胞有一种有效的系统来降低GSSG(5-8)。磷酸葡萄糖酸途径的TPN连接反应与谷胱甘肽还原酶结合，维持红细胞谷胱甘肽的还原状态。在目前的研究中，完整红细胞的过氧化氢酶和过氧化物酶-GSH系统被证明可以保护血红蛋白免受抗坏血酸存在时引起的氧化破坏。当培养液中没有葡萄糖时，过氧化物酶-谷胱甘肽系统的保护作用就会消失。这种故障是由于单元不能降低GSSG造成的。其结果是GSH水平迅速下降，随后失去了过氧化物酶-GSH系统的保护作用。叠氮可消除过氧化氢酶对完整红细胞的保护作用，这一事实已由Foulkes和Lemberg(1)证实。此外，对溶血物的研究表明，在葡萄糖6-磷酸、6-磷酸葡萄糖或5-磷酸核糖存在的情况下，过氧化物酶-GSH保护系统是有效的。此前已发现这三种化合物能有效地将红细胞GSSG还原为GSH。
This protective system has a lasting effect only when the product of the reaction, GSSG, is continuously reduced to GSH. The work of previous investigators has shown that erythrocytes have an effective system for reducing GSSG (5-8). The TPN-linked reactions of the phosphogluconate pathway, in conjunction with glutathione reductase, maintain erythrocyte glutathione in the reduced state. In the present studies, catalase and the peroxidase-GSH system of intact erythrocytes are shown to protect hemoglobin from oxidative breakdown brought about in the presence of ascorbic acid. When glucose is absent from the incubation medium, the protective effect of the peroxidase-GSH system is lost. This failure is due to the inability of the cell to reduce GSSG. The result is a rapid drop in the GSH level and subsequent loss of the protective effect of the peroxidase-GSH system. The protective effect of catalase in intact erythrocytes is eliminated by azide, a fact which has been demonstrated previously by Foulkes and Lemberg (1). In addition, studies with hemolysates show that the peroxidase-GSH protective system is effective in the presence of either glucose 6-phosphate, 6-phosphogluconate, or ribose 5-phosphate. These three compounds have been found previously to be effective in reducing GSSG to GSH in erythro-