Figure 4.

Remyelination Reactivates Ca²⁺ Microdomain Transients and Ca²⁺ Waves

(A) Left: representative MBP immunostainings of layer 5 in control and after 7, 12, and 25 days of remyelination. Scale bars, 50 μm. Right: normalized MBP intensity for the four stages plotted versus the normalized cortical column length. WM, white matter.

(B) Top: images of resting and frame subtracted fractional fluorescence change with time points indicated (x, y, z). Scale bar, 5 μm. Bottom: corresponding Ca²⁺ traces of the ROIs for transient Ca²⁺ events and Ca²⁺ waves from two different trials. The Ca²⁺ wave initiates at the end tip (ROI 1) and propagates toward the center of the sheath (ROI 2). Scale bars, 10% ΔF/F₀ and 2 s.

(C) Ca²⁺ wave probability increases during remyelination (p = 0.039, Fisher exact test).

(D) Ca²⁺ event frequency is increased up to 35 days after remyelination onset.

(E) Histogram of the decay time constant for Ca²⁺ events during remyelination. Inset shows a typical Ca²⁺ event; scale bars, 5% ΔF/F₀ and 1 s.

See also Figure S4.