The metabolism of exogenous L-Dopa in the brain: An immunohistochemical study of its conversion to dopamine in non-catecholaminergic cells of the rat brain
- Cite this article as:
- Tison, F., Mons, N., Geffard, M. et al. J Neural Transm Gen Sect (1991) 3: 27. doi:10.1007/BF02251134
The characterization and localization of non-catecholaminergic cells producing dopamine after L-Dopa load have been investigated in the normal rat brain by a direct immunohistochemical labelling of amines using specific antibodies. The detection of dopamine-containing non-catecholaminergic cells has been achieved in rats given a commonly used mixture of L-Dopa plus peripheral decarboxylase inhibitor, and compared to controls. Results indicate that serotoninergic neurons tend toward a switch of their metabolism into dopamine production after L-Dopa load in a dose-dependent manner. In addition small non-aminergic cells, identified as aromatic amino-acid decarboxylase-containing cells, were observed to produce dopamine after exogenous L-Dopa load. Possible implications of such results concerning the mode of action of L-Dopa in the brain are discussed.