Potassium channels-mediated electrophysiologic responses are inhibited by cytosolic phospholipase A2α ablation
Cytosolic phospholipase A2α (cPLA2α) is implicated in the progression of excitotoxic neuronal injury and cerebral ischemia. Previous work suggests that cPLA2α increases aberrant electrophysiologic events through attenuating K+ channel functions. Nevertheless, which K+ channels are affected by cPLA2α needs to be determined. Here we examined K+ channels-mediated electrophysiologic responses in hippocampal CA1 pyramidal neurons from wild-type and cPLA2α−/− mice using simultaneous patch-clamp recording and confocal Ca2+ imaging. After the exposure to the blockers of Ca2+-sensitive and A-type K+ channels, all CA1 neurons developed spike broadening and increased dendritic Ca2+ transients. These effects were occluded in CA1 neurons from cPLA2α−/− mice. Therefore, cPLA2α modulates the functions of Ca2+-sensitive and A-type K+ channels in neurotoxicity.