ATP-DEPENDENT POTASSIUM CHANNEL FROM RAT- LIVER MITOCHONDRIA - INHIBITORY ANALYSIS, CHANNEL CLUSTERIZATION

The inhibitor of potassium mitochondrial channels quinidine (0.1 mM) c losed the ATP-sensitive potassium channels isolated from mitochondria and reconstituted into a bilayer lipid membrane. Inhibitors of cytopla sm membrane K-channels (ouabain, tetraethyl ammonium, and caesium ions ) produced no effect on the ATP-sensitive mitochondrial K-channels; 0. 5-2 mu M glybenclamide did not affect the reconstituted channels as we ll. The multiplicity of jumps of conductivity at small concentration o f the protein and maintaining of km selectivity at switching various l evels of conductivity leads us to the assumption that the large channe ls are clusters of elementary channels. The average frequency of switc hings channel-cluster between various levels of conductivity is much m ore higher than at the elementary channel.