Anoxia reversibly suppresses neuronal calcium currents in rat hippocampal slices.
Intracellular recording from CA1 neurons confirmed that short periods of anoxia (95% N2 + 5% CO2 for 2-4 min) have a hyperpolarizing action, caused by a rise in K conductance. After blockage of K channels with extracellular Cs+ and tetraethylammonium (or intracellular Cs+), large inward currents of Ca were evoked by depolarizing pulses: transient currents at a holding potential near -70 mV, and more sustained ones near -50 mV. Both types of Ca current were much reduced or fully suppressed after 1-3 min of anoxia, but they largely (or fully) recovered within 1-10 min of starting reoxygenation.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002586:Cesium / Q000378:metabolism; D004553:Electric Conductivity; D004594:Electrophysiology; D006624:Hippocampus / Q000378:metabolism*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D010100:Oxygen / Q000502:physiology*; D011188:Potassium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013757:Tetraethylammonium Compounds / Q000378:metabolism
D007473:Ion Channels; D013757:Tetraethylammonium Compounds; D002586:Cesium; D011188:Potassium; D010100:Oxygen; D002118:Calcium