Synergistic effects of pulsed magnetic field and gamma radiation on mice infected with sendai virus: Preliminary observations

Abstract

Male and female C57NA/Fe mice infected with Sendai virus were subjected to Pulsed Magnetic Fields (PMF) repeating at 15 Hz. Treatment was given 78.5 h prior to, 63.75 h after, and simultaneously with high doses of Co-60 gamma radiation. The virus significantly lowered the LD 50 30 ) of the mice from 8.00 Gy to 6.80 Gy. The reduction in LD 50/30 was not influenced by the application of PMF. In virus-exposed males, PMF reduced Mean Survival Time (MST) at 7.50 Gy. but increased it at 8.50 Gy for mice exposed to the field after irradiation. Simultaneous exposure to PMF and gamma radiation in virus-laden mice demonstrated sexual dimorphism. There was no difference between PMF treated and non-treated males at any of three dose levels, while the females showed increased MST with increasing gamma dose in the presence of PMF, the exact opposite of what would be expected. Comparison tests of old (22–30 weeks) versus young (8–10 weeks) mice showed that the protective effect only appears in young females.