Project/Area Number |
17590110
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Environmental pharmacy
|
Research Institution | Nihon University |
Principal Investigator |
YAMANAKA Kenzo Nihon University, College of Pharmacy, Professor (50182572)
|
Co-Investigator(Kenkyū-buntansha) |
KATO Koichi Nihon University, College of Pharmacy, Assistant Professor (60246931)
|
Project Period (FY) |
2005 – 2006
|
Project Status |
Completed (Fiscal Year 2006)
|
Budget Amount *help |
¥2,700,000 (Direct Cost: ¥2,700,000)
Fiscal Year 2006: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2005: ¥1,700,000 (Direct Cost: ¥1,700,000)
|
Keywords | Environmental carcinogenesis / Arsenic carcinogenesis / Dimethylarsinic acid / Dimethylarsine / Dimethylarsine radical / Dimethylarsine peroxy radical / 発癌プロモーション / 発癌イニシエーション / 酸化ストレス / マウス短期肺発癌実験 / ジメチルアシン / ジメチルヒ素化合粒 / メチル化代謝 |
Research Abstract |
Continuous and laser photolysis studies of (CH_3)_2As^<(III)>I were carried out in methanol solutions. The photoproduct obtained with the continuous photolysis of the aerated solutions was identified as {(CH_3)_2As^(V)(OH)_2}+{(CH_3)_2As^(V)O(OH)}_2][I_3] by X-ray crystallography. The laser flash photolysis of (CH_3)_2As^(III)I in a degassed methanol gives a transient spectrum of dimethylarsine radical, (CH_3)_2As^(III), with a broad peak centered around 560 nm. The arsinous radical, (CH_3)_2As^(III), decays according to second order kinetics to regenerate (CH_3)_2As(III)^I. In the presence of oxygen, (CH_3)_2As^(III) reacts with oxygen to yield the peroxy radicals, [(CH_3)_2As^(III)(O_2)] with the bimolecular rate constant, 2.0 x 10_9 M_-1 s_-1. The peroxy radical having weak and broad absorption in the wavelength region λ> 500 nm decays according to first order kinetics with a rate constant 5.0 x 10_5 s_-1. It is suggested that the peroxy radical unimolecularly converts to (CH_3)_2As^(V)(O)O, which eventually turns to the product {(CH_3)_2As^(V)(OH)_2}+{(CH_3)_2As^(V)O(OH)}_2][I_3].
|