Excitation of hippocampal pyramidal cells by an electrical field effect. Synchronous neural after discharges in rat hippocampal slices without active chemical synapses. Low-calcium field burst discharges of CAl pyramidal neurones in rat hippocampal slices. This process is experimental and the keywords may be updated as the learning algorithm improves. These keywords were added by machine and not by the authors. If such oscillations can be shown to initiate the seizure discharge, and not just be an epiphenomenon, then targeting gap junction conductances may prove useful as an anticonvulsant strategy. It is of note that seizure activity, both in vivo and in vitro, has been observed to begin with very high-frequency oscillations. A by-product of such spread is the ability of axonally-coupled neurons to generate oscillations at very high frequencies (>~70 Hz). Such axon-axon gap junctions promote epileptogenesis not so much by enhancing synchrony, as by providing pathways for the direct spread of action potentials between neurons. Rather, we shall argue for a role for a newly described sort of gap junction, located between the proximal axons of principal neurons.
In this chapter, we shall review evidence that gap junctions can contribute to epileptogenesis in the hippocampus and cortex-but not just any gap junctions.
