Differential gene expression in populations of sympathetic neurons purified from a neuropeptide Y reporter mouse

Using gene chip methodology, we identified candidate genes differentially expressed by vasomotor and non-vasomotor sympathetic neurons in the superior cervical ganglion. Groups of 10 neurons were manually sorted after isolation from a transgenic neuropeptide Y (NPY) reporter mouse that expresses the humanized Renilla green fluorescent protein (GFP) under control of Npy promoter sequences. Anatomical analysis of GFP and NPY co-expression showed that 98% of GFP-positive neurons and 16% of GFP-negative neurons express NPY. The probability of contamination in sorted cell samples was therefore high. To minimize this problem, we screened amplified cDNA samples by the quantitative polymerase chain reaction. This approach identified 101 candidate genes preferentially expressed by GFP-positive neurons and 74 candidate genes preferentially expressed by GFP-negative neurons.