Differential effects of apamin on Ca2+-dependent K+ currents in bullfrog sympathetic ganglion cells.
In B-type neurones of bullfrog sympathetic ganglia, apamin (10 nM) suppressed the Ca2+-dependent K+ current (IAH) involved in the afterhyperpolarization of an action potential, while it did not affect the Ca2+-dependent K+ current (Ic) underlying the spike repolarization. IAH was further separated into two exponential components which were differentially affected by apamin, voltage and alterations in Ca2+ influx, suggesting the existence of 3 different types of Ca2+-dependent K+ channel in bullfrog sympathetic neurones.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001030:Apamin / Q000494:pharmacology*; D001514:Bee Venoms / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D002413:Cations, Divalent / Q000494:pharmacology; D004558:Electric Stimulation; D005728:Ganglia, Sympathetic / Q000378:metabolism / Q000502:physiology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011188:Potassium / Q000378:metabolism*; D011892:Rana catesbeiana; D013997:Time Factors
D001514:Bee Venoms; D002413:Cations, Divalent; D007473:Ion Channels; D001030:Apamin; D011188:Potassium; D002118:Calcium