Figure 6.

Disruption of the domain organization of the node of Ranvier in long-term netrin-1- and DCC-deficient slice cultures. Long-term (60 DIV) cerebellar slice cultures were double-labeled with antibodies against Na⁺ch and Kv1.2 (A–D). Kv1.2 protein was visualized using Alexa 488-conjugated secondary antibodies (green), and Na⁺ch proteins were visualized using Alexa 546-conjugated secondary antibodies (red). In cultures lacking netrin-1 (C) or DCC (D), a reduced distance between Na⁺ channels localized within the node of Ranvier and K⁺ channels normally localized to the juxtaparanodal region was detected. This decrease was primarily attributable to the apparent “leaking” of K⁺ channels into the paranode, and occasionally the node itself (C, D, arrowheads; E). In netrin-1^−/−, but not DCC^−/− slices, the length of the Na⁺ch-positive domain was increased relative to control (C, arrow; F). Magnification: 100× objective; digital zoom, 4. Scale bar, 2 μm. *p < 0.05, **p < 0.005. Error bars indicate SEM.