Striatal tyrosine hydroxylase expressing neurons in mouse models of Parkinson's disease

Tyrosine hydroxylase (TH) expressing neurons were identified in human and monkey striatum and reported to be regulated by dopamine depletion. Only few studies in rodents exist demonstrating transient appearance of TH+ neurons in the striatum after nigrostriatal dopaminergic injury. Using in situ hybridization we found that in mouse brain a subpopulation of striatal neurons express TH mRNA constitutively. After systemic application of the dopaminergic toxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP) the number of striatal TH+ neurons was not significantly changed as compared to saline treated control mic…