[Simultaneous detection of tryptamine and dopamine in the substantia nigra and raphe nuclei in rats using specific antibodies].

Using a double-labelling procedure, morphological relationships existing between dopaminergic and indoleaminergic neuronal systems in rat brain were investigated. Firstly, thanks to a tryptamine (T) antiserum, we visualized this indoleamine in all mesencephalic regions and showed that the T-immunoreactivity (IR) seems to overlap with the staining observed from serotonin (HT) and 5-methoxytryptamine (MT) antisera. Secondly, using a monoclonal anti-dopamine (DA) antibody and our anti-T antibodies, the simultaneous and specific detection of these compounds enabled us to define the chemically relationships existing between the dopaminergic and tryptaminergic neuronal systems from substantia nigra to raphe nuclei. No co-localization exists. But, the intensity of T-IR decreases from the back to the front, whereas the DA-staining decreases in the opposite way, indicating possible interactions at the end of substantia nigra and B9 area.