Single Cl- channels in molluscan neurones: multiplicity of the conductance states.

Properties of the single Cl channels were studied in excised patches of surface membrane from molluscan neurones using single-channel recording technique. These channels are controlled by Ca2+ and K+ acting on cytoplasmic and outer membrane surfaces, respectively, and by the membrane potential. The channels display about 16 intermediate conductance sublevels, each of them being multiples of approximately 12.5 pS. The upper level of the channel conductance is about 200 pS. The channel behavior is consistent with an aggregation of channel-forming subunits into a cluster.