How does one oligodendrocyte myelinate many axons at once? · Grey Matter

An oligodendrocyte sends out several long processes, and the tip of each one flattens into a sheet that winds around a segment of a different axon, layer after layer, forming one internode of myelin.

How does one oligodendrocyte myelinate many axons at once?

An oligodendrocyte sends out several long processes, and the tip of each one flattens into a sheet that winds around a segment of a different axon, layer after layer, forming one internode of myelin. Depending on the region a single cell makes roughly 20 to 60 such segments, up to about 50 in the optic nerve, so one cell serves many axons and each axon is served by many cells along its length. In the peripheral nerves Schwann cells do the same job one segment at a time. The economy has a cost: losing one oligodendrocyte strips myelin from many axons at once.