The spinal cord-ventral root junction in the trembler mouse.

The Trembler mouse suffers from an hereditary demyelinating neuropathy. Schwann cell myelination of peripheral nerve fibres in the Trembler mouse is abnormal. Myelination of central nerve fibres in the deeper layers of white matter of the spinal cord is normal. At the junction between the peripheral nervous system and the central nervous system in the ventral roots in the Trembler mouse central-type nerve fibres are abnormally thinly myelinated. It is suggested that the normal process of myelination of central nerve fibres in this region is affected by abnormalities of the Schwann cell in the peripheral nervous system.