生体抗酸化防御系とメタロチオネイン

概要

論文の詳細を見る
A biological role of metallothionein (MT) as a radical scavenger has been proposed. The hypothesis is based on the following two observations. One is that MT is induced by exposure to radical generating conditions such as paraquat, carbon tetrachloride or fasting. The stimuli induce not only MT synthesis but also oxygen radical formation and lipid peroxidation in the rat liver. However, the enhanced lipid peroxidation does not necessarily induce the MT synthesis, since pretreatment with vitamin E prevented only lipid peroxidation. Possible factors contributing to MT induction should be investigated. The other one is that preinduction of MT prevented lipid peroxidation or toxicity by free radicals without influencing levels of other free radical scavenging factors such as superoxide dismutase, glutathione peroxidase, catalase and non-protein thiol. Cells with high contents of MT were resistant to X-irradiation, which produces hydroxyl radicals. It was, however, shown that free radicals cannot be scavenged efficiently by MT. Further studies are required to establish the role of MT as a radical scavenger in biological anti-oxidant systems.
公益社団法人日本薬学会の論文
1992-06-30