For many years Cl- channels have been well studied in neurological systems, where these channels initiate action potentials at synapses, propagate signals along axons and dendrites, and trigger neurotransmitter release and Calcium influx. These activities play a central role in human physiology. Channels with Cl- conductance outside of the nervous system are traditionally viewed as insignificant partners only required for housekeeping functions. In the body, Cl- channels are associated with the secretions of fluids. It wasn't until recently that these channels were recognized as playing an important role muscle functions, relating to disease such as many Myopathies (Myotonia congenita), Epilepsy, Dent's and Bartter's Syndromes, and Osteopetrosis.
This document gives a basic outline of the ClC Chloride channel family characteristics, their structure, functions, mechanisms of action, and their specific role in skeletal muscle. A specific section is dedicated to the ClC-1 channel and it's role in the pathology Myotonia congenita.