Radioprotection of mouse skin by WR-2721: the critical influence of oxygen tension.
The epidermal clone assay has been used to study the radioprotective effect of WR-2721 on mouse skin under different conditions of oxygenation and under anoxia. The skin has shown a progressive decrease in sensitivity as the inspired gas was changed from 100% oxygen towards 0% oxygen. Compared with mice breathing 100% oxygen, those breathing air are partially protected. The inspired oxygen concentration to given half the full oxygen effect is 10--12%. The radioprotection observed with 400 mg/kg WR-2721 is markedly dependent on the ambient oxygen concentration. The protection factor is 1.1 or less in mice breathing 5%, 1% of 0% oxygen. Protection is maximal (1.95) in air and in 50% oxygen and diminishes to 1.6 at higher oxygen tensions.
D004999:Amifostine / Q000494:pharmacology*; D000818:Animals; D002999:Clone Cells / Q000528:radiation effects; D051379:Mice; D009584:Nitrogen / Q000494:pharmacology; D009946:Organothiophosphorus Compounds / Q000494:pharmacology*; D010100:Oxygen / Q000502:physiology*; D011837:Radiation-Protective Agents; D012867:Skin / Q000528:radiation effects*; D013438:Sulfhydryl Compounds / Q000494:pharmacology
D009946:Organothiophosphorus Compounds; D011837:Radiation-Protective Agents; D013438:Sulfhydryl Compounds; D004999:Amifostine; D009584:Nitrogen; D010100:Oxygen