ON THE MECHANISM OF RADIATION PROTECTION BY CYSTEAMINE: AN INVESTIGATION BY MEANS OF ELECTRON SPIN RESONANCE

Journal Article · Mon Apr 01 04:00:00 EST 1963 · Radiation Res.

DOI:https://doi.org/10.2307/3571394· OSTI ID:4692003

Ormerod, M G; Alexander, P

The presence of cysteamine was found to prevent the crosslinking of deoxyribonucleic acid (DNA) when irradiated by gamma rays in the form of a nucleoprotein. Electron spin resonance measurements of salmon sperm heads indicated that the protection is brought about by the transfer of a hydrogen atom from the --SH group of the cysteamine to the radicals produced in DNA. In this way the radiation damage in DNA is restored, and radical combination leading to crosslinking is prevented. Oxygen competes with the -SH groups for the radioinduced radicals, and repair by cysteamine is more effective in the absence of oxygen. It is suggested that intracellular -SH compounds are responsible for restitution of radiation damage within cells and that interference with the repair reaction by oxygen is one of the factors responsible for the radiosensitizing action of oxygen. Data on the electron spin resonance spectra at -196 un. Concent 85% C and at room temperature of irradiated nucleoprotein and its constituents DNA and salmine are also presented. (auth)

• Research Organization: Royal Military Coll. of Sci., Shrivenham, Berks, Eng. and Chester Beatty Research Inst., London
• Sponsoring Organization: USDOE
• NSA Number: NSA-17-023233
• OSTI ID: 4692003
• Journal Information: Radiation Res., Journal Name: Radiation Res. Vol. Vol: 18
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AMINES
BIOCHEMISTRY
BIOLOGY AND MEDICINE
CROSS-LINKING
DNA
EFFICIENCY
ELECTRONS
FISH
FREE RADICALS
GAMMA RADIATION
GONADS
LOW TEMPERATURE
MEASURED VALUES
NUCLEIC ACIDS
OXYGEN
PROTEINS
RADIATION INJURIES
RADIATION PROTECTION
RADIOSENSITIVITY
RECOVERY
RESONANCE
SALMINE
SALMON
SPECTRA
SPIN