Neuronal degeneration in the brain of the brindled mouse--a light microscope study

The brindled mouse (Mobr) is a neurological mutant mouse with a deficiency in copper transport. This mutant has many clinical as well as biochemical features in common with Kinky hair syndrome (KHS) in humans (Tab. 1). Male hemizygotes (Mobr/Y) are characterized by the absence of fur pigment and curly whiskers. They become inactive, losing weight at around the 10th-12th post-natal day. They usually die in an emaciated state around the 15th-16th postnatal day. The brain weight is usually about three fourths of that of littermate controls. Microscopically, widespread neuronal degeneration was noted in the cerebral cortex and thalamic nuclei of male hemizygotes after the 12th post-natal day. The degeneration continued to increase until death. Scattered degenerated cells were also noted in the cerebellum. No such degenerative changes were observed in the brain of female heterozygotes (Mobr/+) or in normal or starved littermates. These degenerative changes of neurons in the brindled hemizygote mouse will be compared with the neuropathological changes observed in KHS and in experimental animals with copper deficiency, and the possible pathogenesis of these changes will be discussed.