Figure 7.

Summary of results. Interneuron firing (bottom left) stimulated release of GABA, which depolarises pyramidal cells (bottom right) via GABA_A activation and subsequent Cl⁻ efflux. This opens voltage gated Na⁺ channels which produces neuronal Na⁺ fluctuations. Interneuron activty also appears to be responsible for astrocytic fluctuations. These appear to have a separate trigger and mechanism, the source of which remains unclear at present. Abbreviations, see Table 1. NE: nor-epinephrine; Ach: acetylcholine; depol: depolarization; Na_v: TTX-sensitive voltage-gated Na⁺ channel.