Effects of redox agents on the Ca2+-activated K+ channel.
The sensitivity to Ca2+ of the Ca2+-dependent K+ channel can be increased by the artificial electron donor system ascorbate + phenazine-methosulphate in a variety of animal cells. In the human erythrocyte the shift from the 'low' to the 'high-affinity' state seems to depend on the reduction of a membrane component accepting 2 electrons and with an standard redox potential (pH 7.5) of about 47 mV. The relevance of this redox modulation under physiological circumstances is unknown at the moment.
D001205:Ascorbic Acid / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D003574:Cytochrome c Group / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D007473:Ion Channels / Q000378:metabolism*; D008773:Methylphenazonium Methosulfate / Q000494:pharmacology*; D010084:Oxidation-Reduction; D010619:Phenazines / Q000494:pharmacology*; D011188:Potassium / Q000378:metabolism*
D003574:Cytochrome c Group; D007473:Ion Channels; D010619:Phenazines; D008773:Methylphenazonium Methosulfate; D001205:Ascorbic Acid; D011188:Potassium; D002118:Calcium