Intracellular injection of a Ca2+ chelator inhibits spike repolarization in hippocampal neurons.
The Ca-dependence of spike repolarization and afterhyperpolarizations (AHPs) in Ca1 pyramidal cells, was tested with intracellular electrodes containing the Ca buffers EGTA or 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA). EGTA blocked only the slow AHP; but the fast-acting Ca chelator BAPTA also inhibited spike repolarization and the fast AHP. This supports the hypothesis that a fast Ca-activated'K-current contributes to spike repolarization.
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002614:Chelating Agents / Q000494:pharmacology*; D004533:Egtazic Acid / Q000494:pharmacology* / Q000031:analogs & derivatives; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011712:Pyramidal Tracts / Q000187:drug effects / Q000502:physiology; D051381:Rats
D002614:Chelating Agents; D004533:Egtazic Acid; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D002118:Calcium