BK channels promote action potential repolarization in skeletal muscle but contribute little to myotonia.

ABSTRACT: Patients with myotonia congenita suffer from slowed relaxation of muscle (myotonia), due to hyperexcitability caused by loss-of-function mutations in the ClC-1 chloride channel. A recent study suggested that block of large-conductance voltage- and Ca²⁺- activated K⁺ channels (BK) may be effective as therapy. The mechanism underlying efficacy was suggested to be lessening of the depolarizing effect of build-up of K⁺ in t-tubules of muscle during repetitive firing. BK channels are widely expressed in the nervous system and have been shown to play a central role in regulation of excitability, but their contribution to muscle excitability has not been determined. We performed intracellular recordings as well as force measurements in both wild type and BK^-/

SUBMITTER: Dupont C 

PROVIDER: S-EPMC11461784 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature