Identification of nigral dopaminergic neuron-enriched genes in adult rats.

Dopaminergic (DA) neurons in the substantia nigra play crucial roles in movement control and other physiological activities. Degeneration of these neurons is closely associated with Parkinson's disease. However, the molecular identity of nigral DA neurons is not fully understood. To identify nigral DA neuron-enriched genes, we used microarrays to compare the genome-wide gene expression profiles in 6-hydroxydopamine-lesioned, and control, substantia nigra. We identified a total of 88 unique differentially expressed gene transcripts. The spatial expression patterns of a set of these genes, including Slc10a4, Rit2, F2r, Snx10 and Slc24a3, were validated by in situ hybridization. It was revealed that their expression was highly specific in the substantia nigra. Thus we identified a set of genes that are highly expressed in nigral DA neurons, and may be involved in the maintenance and survival of nigral DA neurons in the adult rat brain. Our study also provides a general approach for profiling cell type-specific gene expression in the mature mammalian brain.