著者

三浦 俊明

出版者

関西学院大学

雑誌

人文論究 (ISSN:02866773)

巻号頁・発行日

vol.43, no.3, pp.p1-14, 1993-12

著者

桜井 光一 三浦 俊明 小木曾 健人

出版者

公益社団法人日本薬学会

雑誌

藥學雜誌 (ISSN:00316903)

巻号頁・発行日

vol.106, no.11, pp.1034-1039, 1986

被引用文献数

4

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Protective effects of several hydroxyl radical (HO·) scavengers and superoxide dismutase on alloxan-induced diabetes were studied in vivo. Thiourea, methylthiourea, dimethylthiourea and ethanol, HO· scavengers (type 1), which easily cross cellular membranes, protected initial- and permanent-hyperglycemia. In contrast, mannitol and sorbitol (type 2), which can not cross cellular membranes, protected initial-hyperglycemia, but did not protect permanent-hyperglycemia. Furthermore, superoxide dismutase which is not expected to be incorporated into pancreatic β-cell, strongly protected initial-hyperglycemia but partially protected permanent-hyperglycemia. These results suggest that HO·primarily damages the β-cell membranes by acting at or neat a site involved in insulin release, and subsequently damages the intracellular components. From these results, the possible protective mechanism of these scavengers was discussed.

著者

三浦 俊明 Toshiaki Miura

雑誌

人文論究 (ISSN:02866773)

巻号頁・発行日

vol.43, no.3, pp.1-14, 1993-12-20

著者

三浦 俊明 村岡 早苗 小木曾 健人

出版者

公益社団法人日本薬学会

雑誌

Chemical and Pharmaceutical Bulletin (ISSN:00092363)

巻号頁・発行日

vol.40, no.3, pp.709-712, 1992-03-25

被引用文献数

6

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Semiquinone radicals of menadione were generated during the reaction of menadione with reduced glutathione (GSH), dependent upon the pH. Under aerobic conditions, cytochrome c was reduced during the reaction, and superoxide dismutase (SOD) inhibited the cytochrome c reduction. The inhibitory effect of SOD was greater at a high pH than at a low pH. In the presence of Fe^<3+> or ethylenediaminetetraacetic acid (EDTA)-Fe^<3+>, deoxyribose was degraded during the reaction of menadione with GSH, dependent upon the pH. Greater amounts of deoxyribose were degraded at a low pH than at a high pH. The reduction of Fe^<3+> of EDTA-Fe^<3+> also depended on the pH, and SOD strongly inhibited the Fe^<3+> reduction, indicating that Fe^<3+> or Fe^<3+>-EDTA was reduced by superoxide. SOD, catalase, mennitol and benzoate inhibited the deoxyribose degradation at various pH values. These results indicate that the menadione semiquinone radical is readily formed at an alkali pH but a hydroxyl radical is predominantly produced near a neutral pH. A hydroxyl radical may be generated via an iron-catalyzed Haber-Weiss reaction.

著者

桜井 光一 三浦 俊明 小木曾 健人

出版者

公益社団法人 日本薬学会

雑誌

YAKUGAKU ZASSHI (ISSN:00316903)

巻号頁・発行日

vol.106, no.11, pp.1034-1039, 1986-11-25 (Released:2008-05-30)

参考文献数

21

被引用文献数

4

---

Protective effects of several hydroxyl radical (HO·) scavengers and superoxide dismutase on alloxan-induced diabetes were studied in vivo. Thiourea, methylthiourea, dimethylthiourea and ethanol, HO· scavengers (type 1), which easily cross cellular membranes, protected initial- and permanent-hyperglycemia. In contrast, mannitol and sorbitol (type 2), which can not cross cellular membranes, protected initial-hyperglycemia, but did not protect permanent-hyperglycemia. Furthermore, superoxide dismutase which is not expected to be incorporated into pancreatic β-cell, strongly protected initial-hyperglycemia but partially protected permanent-hyperglycemia. These results suggest that HO·primarily damages the β-cell membranes by acting at or neat a site involved in insulin release, and subsequently damages the intracellular components. From these results, the possible protective mechanism of these scavengers was discussed.