A Killer Potassium Channel
نویسندگان
چکیده
Microglia, the resident immune cells of the brain, are important determinants of CNS inflammation. They play defense in the healthy brain, but microglial activation can also lead to neuronal injury or death. The microglial potassium channel Kv1.3 is involved in microglial proliferation and in the respiratory burst that generates reactive oxygen species such as superoxide; thus Fordyce et al. examined the role of Kv1.3 in microglial-induced neuronal death. The authors used a Transwell culture system in which microglia were activated in a separate chamber and then cocultured with neurons. Expression of microglial Kv1.3 currents increased in activated microglia, whereas block of Kv1.3 reduced the respiratory burst as well as microglia-induced neuronal death. Consistent with an oxidative injury mechanism, peroxynitrite, a toxic product of superoxide and nitric oxide, was involved. However, the Kv1.3-dependent cell-death pathway was independent of the p38 mitogen-activated protein kinase pathway, suggesting that multiple pathways can participate in microglial-induced neurotoxicity.
منابع مشابه
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