THE TREATMENT OF ACUTELY X-IRRADIATED MICE WITH STREPTOMYCIN AND DERIVATIVES OF 6-AMINOPENICILLANIC ACID
A comparison was made between the therapeutic effects of 2 derivatives of 6-aminopenicillanic acid (potassium phenethicillin and methicillin), benzyl penicillin (penicillin G), and streptomycin, in mice given lethal doses of x rays (700 to 1000 r). The LD/sub 50/ in the untreated group was 806 r. None of the antibiotic treatments significantly increased the LD/sub 50/ and one, phenethicillin, appeared to decrease it. Survival time was affected by antibiotic treatment, though in the mice given subcutaneous streptomycin there was a slight prolongation of life not exceeding 2 days. A significantly larger number of deaths occurred in the phenethicillin and methicillin groups than in the control group. The mortality in the streptomycin group was indistinguishable from that of the controls. There were no significant differences in the times to death. The complete failure of streptomycin is at variance with earlier reported results. It is suggested that previous experimental mice may have been infected with streptomycin-sensitive pathogens and that radiation might have caused a flare-up of the hitherto quiescent infection, explaining the favorable action of antibiotics. Thus, streptomycin, or any other antibiotic, can only be expected to be effective if death after irradiation can be attributed to infection. The apparent toxicity of derivatives of 6-aminopenicillanic acid is unexplained. As no toxic effect was found in normal animals at amounts 25 times as large; they may cause a potentiation of the effects of radiation on the basis of their chemical nature. (H.H.D.)
- Research Organization:
- Medical Research Council, Harwell, Berks, Eng.
- NSA Number:
- NSA-17-005917
- OSTI ID:
- 4750211
- Journal Information:
- Brit. J. Exptl. Pathol., Vol. Vol: 43; Other Information: Orig. Receipt Date: 31-DEC-63
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Studies on the effects of gamma radiation on 6-aminopenicillanic acid and its derivatives by the EPR method
Antibiotic radioprotection of mice exposed to supralethal whole-body irradiation independent of antibacterial activity. [Gamma radiation, streptomycin, kanamycin, neomycin, gentamycin]