著者

青柳 一正

出版者

一般社団法人 日本内科学会

雑誌

日本内科学会雑誌 (ISSN:00215384)

巻号頁・発行日

vol.80, no.6, pp.936-940, 1991-06-10 (Released:2008-06-12)

参考文献数

16

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各種の疾患において活性酸素が組織障害の直接的な原因物質であることが判明してきた.原子や分子が不対電子を有するとフリーラジカルと呼ばれ,一般に高い反応性を持つ.酸素がその分子の場合,活性酸素と呼ぶ.高い反応性を持つ活性酸素は生体に重要な物質の合成反応に用いられるが,制御されない物質の酸化は物質の変性を起こし,さらなる傷害を起こす.腎疾患を例にとると尿毒症の発症に伴い生成が著しく増加するメチルグアニジンは活性酸素とクレアチニンの反応生成物である.また,ネフローゼを起こすピューロマイシンアミノヌクレオシドは細胞における活性酸素の産生を増加させ,その産生増加はアラキドン酸代謝やPAFと関連していることが示唆された.外因物質による生体内の活性酸素の増加は,発癌や老化との関連があり,また,細胞における活性酸素の産生調節は疾病の治療薬の開発にとって重要である.

著者

竹村 克己 青柳 一正 永瀬 宗重 坂本 まさ子 石川 敏子 成田 光陽

出版者

社団法人 日本腎臓学会

雑誌

日本腎臓学会誌 (ISSN:03852385)

巻号頁・発行日

vol.32, no.11, pp.1195-1201, 1990 (Released:2011-03-01)

参考文献数

19

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Methylguanidine (MG) which is known as a uremic toxin, is synthesized from creatinine(Cre). We have clarified that active oxygen plays an important role on MG synthesisin vitro and in rat hepatocytes. On the other hand, hyperoxia is very injurious in various tissues, and it has been reported that active oxygen produced in hyperoxia plays an important role on the tissue injury. This study was performed to investigate the effect of hyperoxia on MG synthesis in vivo. The subjects in this study were patients who were treated by hyperbaric oxygen therapy (HBO), Serum Cre, MG, and urinary Cre, MG before and after HBO were measured in these subjects. The subjects were classified into four groups. Group 1-III were undergone HBO with condition of 100% 02, 2 atomosphere absolute (ATA), 1 hour, (I: Ccr<10 ml/min, II: l0≤Ccr<50 m1/min, III: Ccr≥50ml/min) and group IV (Ccr≥50ml/min) with 100%O2, 3ATA. 1 hour. Urinary excretion rate of MG (urine MG/urine Cre) significantly increased after HBO therapy in every group. Urine MG/urine Cre/serum Cre ratio which was used as a index of MG synthesis rate also increased. In this study, it is clarified that MG excretion rate increases in hyperoxic condition. These results suggest that active oxygen plays an important role on MG synthesis in vivo, and that the urine MG/urine Cre/serum Cre ratio can be a uaeful maker of the active oxygen products in vivo.