K efflux pathways and neurotransmitter release associated to hippocampal ischemia: effects of glucose and of K channel blockers

Ischemia of hippocampal slices leads to⁸⁶Rb⁺ efflux and to amino acid neurotransmitter release. This⁸⁶Rb⁺ efflux which corresponds to the massive K⁺ efflux from neuronal cells observed in ischemic animals is inhibited by glucose (IC₅₀ = 1.7mM). Glucose also inhibi the ischemia induced liberation of GABA and aspartate.⁸⁶Rb⁺ efflux is insensitive to any type of known blockers for ATP-sensitive, Ca²⁺-sensitive and voltage-sensitive K⁺ channels.