Dopaminergic (DAergic) neurons of substantia nigra (SN) and ventral tegmental area (VTA) release dopamine on their target neurons in striatum and nucleus accumbens respectively. Recent studies demonstrated that DAergic neurons in culture are able to release glutamate at synapses. We showed that close to 80% of isolated DAergic neurons in culture express the vesicular glutamate transporter 2 (VGluT2). However, only a small sub-population of DAergic neurons in the rostral linear nucleus expresses VGluT2 in vivo (Kawano et al., SFN 2004, 505.4). We hypothesize that VGLUT2 expression in DAergic neurons may be induced under pathological conditions. To study VGluT2 regulation in DAergic neurons in vivo we used double in situ hybridization to localize VGluT2 and tyrosine hydroxylase (TH) mRNA. We examined VGluT2 expression in DAergic neurons during embryonic and postnatal (PN) development. At embryonic days 14 and 15, VGluT2 and TH labelling displayed significant overlap. In PN mesencephalon a quantitative analys...