In vitro maturation of mesencephalic dopaminergic neurons from mouse embryos is enhanced in presence of their striatal target cells.

Long-term survival of mesencephalic and striatal cells from mouse embryos in dissociated primary cultures is described. Catecholaminergic neurons in mesencephalic culutres were identified histochemically and by measuring [3H]dopamine uptake and synthesis from [3H]tyrosine. According to experiments using specific inhibitors of catecholamine uptake, at least two-thirds of the catecholaminergic neurons are dopaminergic. These neurons differentiated whether or not striatal target cells were present, but striatal cells stimulated the development of the dopaminergic neurons. [3H]Dopamine uptake was increased by at least 2-fold regardless of the age of the cocultures (4-15 days). Enhanced [3H]dopamine synthesis was also observed (at least 2-fold) at later times (12-15 days).