Time dependence of the calcium-activated potassium current.
We investigated the dependence of the kinetics of the Ca2+-activated K+ current of the molluscan neuron soma upon membrane potential. The K+ current was activated by intracellular Ca2+ ion injection in neurons with blocked inward Na+ and Ca2+ currents. The difference between currents was measured with brief pulses (less than 100 ms) before and immediately after Ca2+ injection and was used as the Ca2+ activated K+ current at difference membrane potentials. The results in normal (10 mM) and in high (200 nM) external K+ show that the time-course of the Ca2+-activated K+ current depends upon membrane voltage and that the current activates more rapidly with membrane depolarization.
D000818:Animals; D001048:Aplysia; D001693:Biological Transport, Active / Q000187:drug effects; D002118:Calcium / Q000494:pharmacology*; D005724:Ganglia / Q000187:drug effects / Q000502:physiology*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011188:Potassium / Q000378:metabolism*
D011188:Potassium; D002118:Calcium