Summary
Lowering extracellular [Ca2+] in rat hippocampal slices induces spontaneous epileptiform activity in area CA1, which is characterized by rhythmic burst firing of CA1 neurons and by prolonged negative potential shifts at the pyramidal cell body layer. This activity is accompanied by transient decreases of [Na+] and increases of [K+] in the extracellular space. In spite of the complete blockade of synaptic transmission, the wave of epileptiform activity propagates across area CA1. These findings suggest, that non-synaptic mechanisms may play a role in the generation and spread of epileptiform activity in the mammalian CNS.
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Supported by DFG grants He 1128/2-2 and He 1128/3. Y.Y. was supported by an ETP training grant and by the Meller Endowment Fund
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Yaari, Y., Konnerth, A. & Heinemann, U. Spontaneous epileptiform activity of ca1 hippocampal neurons in low extracellular calcium solutions. Exp Brain Res 51, 153–156 (1983). https://doi.org/10.1007/BF00236813
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DOI: https://doi.org/10.1007/BF00236813