Articles: chronic-pain.
-
Painful peripheral neuropathy is a significant clinical problem; however, its pathological mechanism and effective treatments remain elusive. Increased peripheral expression of tetrodotoxin-resistant voltage-gated sodium channel 1.8 (NaV1.8) has been shown to associate with chronic pain symptoms in humans and experimental animals. Sciatic nerve entrapment (SNE) injury was used to develop neuropathic pain symptoms in rats, resulting in increased NaV1.8 mRNA in the injured nerve but not in dorsal root ganglia (DRG). ⋯ Levels of heteronuclear NaV1.8 RNA were unaffected by SNE or shRNA treatments, suggesting that transcription of the Scn10a gene encoding NaV1.8 was unchanged. Based on these data, we postulate that increased axonal mRNA transport results in accumulation of functional NaV1.8 protein in the injured nerve and the development of painful neuropathy symptoms. Thus, targeted delivery of agents that interfere with axonal NaV1.8 mRNA may represent effective neuropathic pain treatments.
-
Randomized Controlled Trial
Ten sessions of adjunctive left prefrontal rTMS significantly reduces fibromyalgia pain: a randomized, controlled pilot study.
Transcranial magnetic stimulation (TMS) of the prefrontal cortex can cause changes in acute pain perception. Several weeks of daily left prefrontal TMS has been shown to treat depression. We recruited 20 patients with fibromyalgia, defined by American College of Rheumatology criteria, and randomized them to receive 4000 pulses at 10 Hz TMS (n=10), or sham TMS (n=10) treatment for 10 sessions over 2 weeks along with their standard medications, which were fixed and stable for at least 4 weeks before starting sessions. ⋯ Pain reduction preceded antidepressant effects. TMS was well tolerated, with few side effects. Further studies that address study limitations are needed to determine whether daily prefrontal TMS may be an effective, durable, and clinically useful treatment for fibromyalgia symptoms.