Abstract
Parkinson’s disease (PD) is a neurodegenerative disorder associated with a progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN), leading to a loss of dopamine in the striatum. One of the experimental therapeutic approaches in PD is the graft of DA neurons not in their ontogenic site, the SN, but directly into the target region, the striatum and those leads to variable results. In this study, we have analyzed in detail the functional outcome of fetal VM tissue expressing GFP under the control of a tyrosine hydroxylase promoter grafts placed either into the SN or striatum in unilaterally 6-hydroxydopamine lesioned adult mice. Anatomical and functional outcome were analyzed using behavioral, electrophysiological and immunohistochemical approaches. Our results show that transplanted neurons in both locations can survive and re-innervate the striatum. Furthermore, both grafts locations significantly restored motor performance and induced the recovery of striatal firing properties. However, only intranigral transplantation allows recovery of fine motor skills of previous members and efficiently normalized cortico-striatal responses.