Naltrexone-sensitive analgesia following exposure of mice to 2450-MHz radiofrequency radiation.
To determine whether exposure to radiofrequency radiation (RFR) would induce sufficient thermal stress to activate endogenous opioid mechanisms, male Swiss Webster mice were exposed to 10, 15, and 20 mW/cm2 RFR in a 2450-MHz waveguide system for 10 min at specific absorption rates (SARs) of 23.7, 34.6, and 45.5 W/kg, respectively, then tested in the abdominal constriction paradigm. Confinement in the RFR exposure chamber alone did not appreciably alter body temperature but did appear to induce a stress-associated analgesia that was not blocked by naltrexone. Exposure of confined mice to RFR raised body temperature and further increased analgesia in an SAR-dependent manner. The high SAR-induced analgesia, but not the hyperthermia, was blocked by naltrexone. These findings suggest that 1) RFR produces SAR-dependent hyperthermia and analgesia, and 2) RFR-induced analgesia is mediated by opioid mechanisms while confinement-induced analgesia involves nonopioid mechanisms.
Maillefer
R H
RH
Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford 61107.
Quock
R M
RM
D000698:Analgesia; D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects*; D001831:Body Temperature / Q000187:drug effects / Q000528:radiation effects; D006358:Hot Temperature; D008297:Male; D051379:Mice; D009271:Naltrexone / Q000494:pharmacology*; D011846:Radio Waves; D013315:Stress, Psychological / Q000503:physiopathology
D009271:Naltrexone