Puymirat J, Barret A, Picart R, Vigny A, Loudes C, Faivre-Bauman A, Tixier-Vidal A
Neuroscience. 1983 Nov;10(3):801-10. doi: 10.1016/0306-4522(83)90217-8.
In dissociated hypothalamic cell cultures of 16-day mouse embryos, growing in chemically defined medium, the catecholaminergic neurons were identified by autoradiography after labelling with [3H]dopamine and by immunocytochemistry with an anti-tyrosine hydroxylase antibody. Using selective inhibitors of amine transport and radioenzymatic determination of amine levels in these cultures, we show that these neurons were mostly dopaminergic. The number of dopaminergic neurons identified by the two techniques increased between days 5 and 8 and decreased after 15 days in vitro. The same number of neurons were identified by autoradiography and by immunocytochemistry and consisted of fusiform and multipolar neurons. The proportion of both types remained steady until 15 days in vitro. Under these conditions, the addition of triiodothyronine (10(-9) M) at the initiation of the culture increased the size but not the number of dopaminergic neurons after 8 days in vitro. Furthermore, triiodothyronine significantly increased the dopaminergic neurite length and arborization. This morphological effect of triiodothyronine was associated with an increase of 35% in [3H]dopamine uptake. Our study shows that hypothalamic dopaminergic neurons are responsive to triiodothyronine which acts as a maintenance or trophic factor having an effect on neurite extension and arborization.
在化学限定培养基中生长的16日龄小鼠胚胎的离体下丘脑细胞培养物中，在用[3H]多巴胺标记后通过放射自显影以及用抗酪氨酸羟化酶抗体进行免疫细胞化学鉴定儿茶酚胺能神经元。使用胺转运的选择性抑制剂并通过放射酶法测定这些培养物中的胺水平，我们表明这些神经元大多是多巴胺能的。通过这两种技术鉴定的多巴胺能神经元数量在体外培养的第5天至第8天增加，在15天后减少。通过放射自显影和免疫细胞化学鉴定出相同数量的神经元，它们由梭形和多极神经元组成。在体外培养15天之前，这两种类型的比例保持稳定。在这些条件下，在培养开始时添加三碘甲状腺原氨酸（10^(-9) M）在体外培养8天后增加了多巴胺能神经元的大小，但没有增加其数量。此外，三碘甲状腺原氨酸显著增加了多巴胺能神经突的长度和分支。三碘甲状腺原氨酸的这种形态学作用与[3H]多巴胺摄取增加35％相关。我们的研究表明，下丘脑多巴胺能神经元对三碘甲状腺原氨酸有反应，三碘甲状腺原氨酸作为一种维持或营养因子，对神经突的延伸和分支有影响。
