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研究了氧和剂量率对免肝金属硫蛋白（ＭＴ－Ｉ）稀水溶液γ辐解的影响。水辐解产生的ＯＨ自由基主要进攻ＭＴ－Ｉ中半胱氨酸残基上的巯基，使巯基与金属离子间的配位键破坏，造成部分金属离子解高，并形成二硫键。而二硫键的形成主要发生在分子内部，其Ｇ值将为分子间二硫键Ｇ值的５倍。Ｎ２Ｏ饱和与Ｎ２饱和时ＭＴ－Ｉ稀水溶液辐解，巯基损失Ｇ值分别为７．０与４．２，Ｏ２饱和时有一较短的链反应。辐解形成的二硫键能定量地被还原型谷胱苷肽还原。同时对ＭＴ－Ｉ稀水溶液γ辐解机理进行了讨论，并求得了辐解时的物料平衡。
Effects of oxygen and dose rates on the γ-radiolysis of a dilute aqueous solution of liver-derived metallothionein (MT-I) were studied. OH radical generated by water radiolysis mainly attacks the sulfhydryl group on the cysteine residue in MT-I, which destroys the coordination bond between the sulfhydryl group and the metal ion, resulting in the dissociation of some metal ions and the formation of disulfide bonds. The disulfide bond formation occurs mainly in the molecule, its G value will be intermolecular disulfide bond G value of 5 times. When N2O saturation and N2 saturated MT-I diluted solution radiate, the G value of sulfhydryl loss is 7.0 and 4.2, respectively, and there is a short chain reaction when O2 is saturated. Disulfide bonds formed by radiolysis can be quantitatively reduced by reduced glutathione. At the same time, the mechanism of γ-radiolysis of dilute aqueous solution of MT-I was discussed, and the material balance during radiolysis was obtained.