Fig. 1.

Selective expression of Oct3 in the brain. Coronal mouse brain sections (A–N) were immunolabeled with antibodies against Oct3 in combination with either anti-TH (dopaminergic marker), anti-GFAP (astrocytic marker), or anti-MAP2 (neuronal marker). Oct3 colocalized with GFAP in the nigrostriatal region (D–F and J–L) but not with astrocytes in other regions (M and N). Although not detectable in dopaminergic structures (A–C and G–I), Oct3 immunoreactivity was detectable in other neurons (K, M, and N). The expression of Oct3 was further confirmed in cells captured by laser capture microdissection followed by quantitative real time RT-PCR analysis (O; BD, below detection). Primarily based on specific cellular markers, at least 800–1,000 cells of each type were captured. In postmortem human samples (P–V), OCT3 (blue–gray appearance) was robustly expressed in cells with morphology resembling that of nondopaminergic neurons (Q, T, and U) and astrocyte-like cells (S) but not in dopaminergic neurons (brown pigment of neuromelanin; P and R). As a negative control, Oct3 antibody was preabsorbed with Oct3 peptide and incubated with an adjacent cerebellar section (V). [Scale bars: 20 μm (A–N); 400 μm (P and T); and 100 μm (Q–S, U, and V)].