Abstract
A new mutant rat strain with movement disorders has arisen spontaneously in a closed colony of Albino–Swiss rats at the Department of Anatomy, Glasgow University. The animals possess a progressive locomotor disorder which is first apparent at around post‐natal day 10. We here report that tyrosine hydroxylase immunocytochemistry demonstrates that these mutants have profound depletions in dopaminergic systems in the substantia nigra and corresponding areas of neostriatum.