Brief Communication Reconstitution and Characterization of a Calcium-Activated Channel From Heart
نویسندگان
چکیده
This paper is the first description of a calcium-activated nonspecific cation channel in adult ventricular muscle. We report gating kinetics and ionic selectivity data from experiments performed at the single channel level. Calcium activation is described by a gating model wherein two ions are involved in the reaction. Channel gating exhibited marked voltage dependence. Ionic selectivity experiments indicated that the channel is cation-selective but unable to discriminate between Na and K. We discuss evidence that this channel mediates transient inward current in ventricular tissue; thus, the channel may be involved in afterdepolarization-induced cardiac arrhythmias. (Circulation Research 1988;62: 411-415)
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