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, Volume 3, Issue 6, pp 471–476 | Cite as

Naltrexone blocks RFR‐induced DNA double strand breaks in rat brain cells

  • Henry Lai
  • Monserrat Carino
  • Narendra Singh


Previous research in our laboratory has shown that various effects of radiofrequency electromagnetic radiation (RFR) exposure on the nervous system are mediated by endogenous opioids in the brain. We have also found that acute exposure to RFR induced DNA strand breaks in brain cells of the rat. The present experiment was carried out to investigate whether endogenous opioids are also involved in RFR‐induced DNA strand breaks. Rats were treated with the opioid antagonist naltrexone (1 mg/kg, IP) immediately before and after exposure to 2450 MHz pulsed (2 µs pulses, 500 pps) RFR at a power density of 2 mW/cm2 (average whole body specific absorption rate of 1.2 W/kg) for 2 hours. DNA double strand breaks were assayed in brain cells at 4 hours after exposure using a microgel electrophoresis assay. Results showed that the RFR exposure significantly increased DNA double strand breaks in brain cells of the rat, and the effect was partially blocked by treatment with naltrexone. Thus, these data indicate that endogenous opioids play a mediating role in RFR‐induced DNA strand breaks in brain cells of the rat.


Power Density Absorption Rate Electromagnetic Radiation Strand Break Naltrexone 
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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Henry Lai
    • 1
  • Monserrat Carino
    • 1
  • Narendra Singh
    • 1
  1. 1.Bioelectromagnetics Research Laboratory, Department of BioengineeringUniversity of WashingtonSeattleUSA

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