Erickson S L, Akil M, Levey A I, Lewis D A
Department of Neuroscience, University of Pittsburgh, PA 15213, USA.
Cereb Cortex. 1998 Jul-Aug;8(5):415-27. doi: 10.1093/cercor/8.5.415.
Dopamine afferents from the mesencephalon appear to play a critical role in the normal development and cognitive functions of multiple areas of the primate cerebral cortex. In some regions, such as the prefrontal and motor cortices, dopamine innervation changes substantially during postnatal development. However, little is known about the postnatal maturation of dopamine afferents to the primate rostral entorhinal cortex, a periallocortical region that receives a dense dopamine innervation in adults. In this study, we used immunocytochemical techniques and antibodies against tyrosine hydroxylase and the dopamine transporter to examine the postnatal development of dopamine axons in the rostral subdivision of macaque monkey entorhinal cortex. Within animals, the axons labeled with each antibody did not differ in overall density or laminar distribution. Across development, the density of dopamine axons in layers I and VI did not change appreciably. In contrast, the density of labeled axons in layer III significantly increased by a factor of three between birth and 5-7 months of age. The timing of this change differs substantially from that observed in prefrontal cortex, where peak dopamine innervation occurs between 2 and 3 years of age. These findings, in concert with other data, suggest that developmental changes in the dopamine innervation of cortical regions may parallel the functional maturation of those areas.
来自中脑的多巴胺传入神经似乎在灵长类动物大脑皮层多个区域的正常发育和认知功能中起着关键作用。在一些区域，如前额叶和运动皮层，多巴胺神经支配在出生后发育过程中会发生显著变化。然而，对于多巴胺传入神经到灵长类动物吻侧内嗅皮层（成年时接受密集多巴胺神经支配的一个近allocortical区域）的出生后成熟情况知之甚少。在这项研究中，我们使用免疫细胞化学技术以及针对酪氨酸羟化酶和多巴胺转运体的抗体，来研究猕猴内嗅皮层吻侧亚区多巴胺轴突的出生后发育。在动物体内，用每种抗体标记的轴突在总体密度或层状分布上没有差异。在整个发育过程中，I层和VI层中多巴胺轴突的密度没有明显变化。相比之下，出生到5 - 7个月大期间，III层中标记轴突的密度显著增加了两倍。这种变化的时间与前额叶皮层中观察到的情况有很大不同，在前额叶皮层中，多巴胺神经支配的峰值出现在2到3岁之间。这些发现与其他数据一致，表明皮层区域多巴胺神经支配的发育变化可能与这些区域的功能成熟平行。
