Figure 6.

K⁺ wave propagation speed proportional to total neuronal surface area in slice. SD initiated in perfused and hypoxic slices (no reperfusion) by introducing a 100-μm-radius central 70 mm spherical K⁺ bolus. A–E, Effects of varying S/V of each cell while maintaining a constant β_nrn (A); varying β_nrn while keeping S/V constant, thus allowing S_nrn to vary (B); varying cell density while keeping constant S_nrn and vol_nrn, thus allowing β_nrn to vary (C); and varying cell density while keeping β_nrn and S/V constant, thus allowing S_nrn and vol_nrn to vary (D). E, Pooled results: K⁺ wave speed increased linearly with total neuronal surface area in both perfused and hypoxic slices. Hypoxia increased wave speed across conditions (0 speed indicates no SD).