The selective degeneration of A9 dopaminergic neurons in the substantia nigra pars compacta (SNpc) in Parkinson’s disease is well recognised while other dopaminergic cells, such as those found in the neighbouring A8 and A10 cell groups, are relatively resistance to death in this disorder. Even within the SNpc, however, the loss of dopaminergic cells is not homogeneous, as cells in the ventral tier of this nucleus are devastated, whilst those in the dorsal tier and in the medial cell group, are relatively spared. The overall aim of this work is to identify subtle differences in protein expression in the dopaminergic cells of the SNpc which might underlie the variable vulnerability of SNpc neurons in Parkinson’s disease. We have identified a number of proteins reported in the literature to be differentially expressed in SNpc neurons, although most of this work is based upon differences seen in the rodent brain. Using immunohistochemistry we are exploring the expression of particular proteins in the vulnerable ventral, and in the resistant dorsal, SNpc cells in the human brain. Results from this project will explain why specific cells are more vulnerable to death in Parkinson’s disease. This knowledge will be important for the development of novel preventative and therapeutic strategies for this disorder. Key researchers: Stefanie Reyes
