Penetration of ruthenium red into peripheral nerve fibers.

Abstract

AbstractLiving peripheral nerves immersed in ruthenium red‐Ringer solution in vivo or in vitro and subsequently fixed for electron microscopy reveal dye in the axon and myelin‐Schwann sheath. There is rapid penetration into the agranular reticulum of the axon first at the node of Ranvier and later in the internodal region. Dye is also sequestered in the Schwann cell body, Schmidt‐Lanterman cleft and adaxonal and paranodal Schwann cytoplasm. Moreover, dye is deposited in the major electron dense line of the myelin wrapping.