Analgesic effect of magnetic stimulation on paclitaxel-induced peripheral neuropathic pain in mice

Peripheral neuropathies are common side effects of chemotherapeutic drugs, including taxanes, platinum-based drugs, vinca alkaloids, and thalidomide. The most common symptoms are numbness, tingling and/or burning pain in a stocking-glove distribution. Severe peripheral neuropathies result in dose reductions, a change in chemotherapy regimen, or early cessation of chemotherapy. There are no proven interventions to prevent or treat chemotherapy-induced peripheral neuropathy. We designed and built a unique magnetic stimulator to clarify the effects of magnetic stimulation in the mouse paclitaxel-induced peripheral neuropathic pain model. Magnetic stimulation significantly reversed paclitaxel-induced mechanical hyperalgesia. The analgesic efficacy of magnetic stimulation was inhibited by naloxone, a μ opioid receptor antagonist. These findings indicate that the analgesic effect of magnetic stimulation is likely to be mediated by the endogenous opioid system. Furthermore, a combination of magnetic stimulation and pregabalin, a Ca(2+) channel blocker, induced a potent combinational analgesic effect, suggesting that analgesic drug dose reduction might be possible. These findings indicate that there is a potential therapeutic utility for magnetic stimulation in pain relief.