Gap junction blocker modulates the spatiotemporal propagation pattern of seizure-like activity.

<p>(A) Typical seizure-like activity before and after the application of CBX. The black and red lines indicate the segments are enlarged below. (B) The ictal-tonic phase of seizure-like activity (black line in A) was magnified. The spatiotemporal change in 2D-CSD was plotted according to different time-points. Notice that sink signals (blue) were more concentrated in layer V during the ictal-tonic phase after the application of 50 µM CBX. Sink signals were enhanced in the superficial layer. During the clonic phase, sink signals were enhanced in layer V and decreased in layer II/III after the application of CBX. (C) A typical seizure-like event was divided into ictal-tonic and clonic phases. The 2D-CSD pseudocolor map shows the spatiotemporal evolution of seizure-like activity without thalamic inputs under the influence of CBX. (D) The patterns of sink-source distributions from five different slices were superimposed. (E) The statistical results showed that sink signals significantly increased in layer II/III and decreased in layer V after the application of CBX during the ictal-tonic phase. Source signals significantly increased in layer V and decreased in layer VI. During the clonic phase, sink signals significantly increased in layer V and decreased in layer II/III, whereas source signals significantly increased in layer II/III after CBX application. (F) The statistical results showed that the sink signals were located in layer V when the thalamic inputs were intact, whereas source signals were also located in layer V during the ictal-tonic phase. Removing the thalamic inputs did not significantly change the sink-source distribution during the ictal-tonic phase. In the clonic phase, removing the thalamic inputs significantly increased sink signals in layer V and decreased them in layer VI, whereas source signals were enhanced in layers V and VI.