Focal axonal swellings in rat cerebellar Purkinje cells during normal development.

Focal axonal swellings are characteristic of a wide range of neuropathies. Three neuron-specific monoclonal antibodies have been used to identify focal axonal swellings in the normal developing rat cerebellar cortex. Between 7 and 15 days postnatal, swellings are a common feature of the granular layer and white matter tracts. Using a Purkinje cell-specific antibody, the majority of swellings were shown to occur in Purkinje cell axons. Focal axonal swellings therefore seem to be a normal adjunct of Purkinje cell maturation.