Mitigating Effects of Radon Inhalation on Neuropathic Pain in Mice and its Possible Application in Veterinary Care

Radon therapy using radon gas is performed in several countries. The main indications of this therapy are for pain-related diseases. Although several clinical studies have been reported, the mechanism underlying radon’s beneficial effects is still unknown. We have demonstrated that low-dose Xor γ-irradiation activates antioxidant functions and inhibits several kinds of oxidative damage in mice. We have also proved that radon inhalation has similar effects to Xor γ-irradiation in mice. Therefore, we attempted to examine whether radon inhalation has mitigating effects on neuropathic pain. Results show that radon inhalation has preventive and curative effects on chronic constriction injury (CCI)-induced neuropathic pain in mice and that these are due to the activation of antioxidant functions. Moreover, we compared the mitigating effects of radon and pregabalin on CCI-induced neuropathic pain in mice. The results showed that the alleviating effects of radon inhalation at a concentration of 1000 Bq/ m3 for 24 hours were of the same level as those achieved by treatment with pregabalin at 1.4 mg/kg body weight. The combined effects of radon and pregabalin (3mg/kg body weight) were almost equivalent to treatment with pregabalin at 4.1mg/kg body weight. These findings suggested that this combined action results in an additive effect and that activation of antioxidant functions by radon inhalation contributes to mitigating effects. Although radon exposure systems for veterinary care were developed, there are no reports on the application of radon therapy to veterinary neuropathic pain. Radon therapy can be useful in Chapter 1