Ichinohe N, Teng B, Kitai S T
Hirosaki University, Department of Anatomy, School of Medicine, Japan.
Anat Embryol (Berl). 2000 Jun;201(6):435-53. doi: 10.1007/s004290050331.
The morphological organization of the tegmental pedunculopontine nucleus, midbrain extrapyramidal area, substantia nigra and subthalamic nucleus and their interrelationships were studied in rat organotypic culture using immunohistochemistry and NADPH-diaphorase histochemistry. Three coronal sections, one containing the tegmental pedunculopontine nucleus/midbrain extrapyramidal area, another with the substantia nigra and the third with the subthalamic nucleus, were obtained from postnatal 1-2-day-old rats. These sections were co-cultured for 3-4 weeks using the roller-tube technique. In the tegmental pedunculopontine nucleus/midbrain extrapyramidal area, the distribution pattern of cholinergic neurons was similar to that found in the in vivo study. We could, therefore, identify the subdivisions of the tegmental pedunculopontine nucleus (i.e., pars compacta and pars dissipata) and the midbrain extrapyramidal area. As in the in vivo situation, glutamate immunoreactive neurons were also located in these areas. Approximately 10% of NADPH-diaphorase positive neurons in the tegmental pedunculopontine nucleus, were glutamate immunoreactive. In the substantia nigra, as in the in vivo, tyrosine hydroxylase immunoreactive (putative dopaminergic) neurons were identified predominantly in the substantia nigra pars compacta, and parvalbumin immunoreactive neurons (putative GABAergic) mainly in the substantia nigra pars reticulata. The subthalamic nucleus was ladened with glutamate immunoreactive neurons. NADPH-diaphorase stained axons originating from the tegmental pedunculopontine nucleus were traced into the substantia nigra and subthalamic nucleus. They were often in close apposition to tyrosine hydroxylase immunoreactive neurons in the substantia nigra. Parvalbumin immunoreactive fibers from the substantia nigra projected heavily to the midbrain extrapyramidal area, but only sparsely to the tegmental pedunculopontine nucleus and the subthalamic nucleus. These findings indicate that the tegmental pedunculopontine nucleus/midbrain extrapyramidal area, substantia nigra and subthalamic nucleus in the organotypic culture have retained a basic morphological organization and connectivity similar to those seen in the in vivo situation. Therefore, this preparation could be a useful model to conduct further studies to investigate functional circuits among the structures represented.
采用免疫组织化学和NADPH黄递酶组织化学方法，在大鼠器官型培养物中研究了被盖脚桥核、中脑锥体外系区、黑质和丘脑底核的形态组织及其相互关系。从出生后1 - 2日龄大鼠获取三个冠状切片，一个包含被盖脚桥核/中脑锥体外系区，另一个含黑质，第三个含丘脑底核。这些切片采用滚管技术共培养3 - 4周。在被盖脚桥核/中脑锥体外系区，胆碱能神经元的分布模式与体内研究中发现的相似。因此，我们能够识别被盖脚桥核（即致密部和分散部）和中脑锥体外系区的亚区。与体内情况一样，谷氨酸免疫反应性神经元也位于这些区域。在被盖脚桥核中，约10%的NADPH黄递酶阳性神经元是谷氨酸免疫反应性的。在黑质中，与体内情况相同，酪氨酸羟化酶免疫反应性（假定为多巴胺能）神经元主要在黑质致密部被识别，而小白蛋白免疫反应性神经元（假定为γ-氨基丁酸能）主要在黑质网状部。丘脑底核富含谷氨酸免疫反应性神经元。源自被盖脚桥核的NADPH黄递酶染色轴突被追踪到黑质和丘脑底核。它们常常与黑质中酪氨酸羟化酶免疫反应性神经元紧密相邻。来自黑质的小白蛋白免疫反应性纤维大量投射到中脑锥体外系区，但仅稀疏投射到被盖脚桥核和丘脑底核。这些发现表明，器官型培养物中的被盖脚桥核/中脑锥体外系区、黑质和丘脑底核保留了与体内情况相似的基本形态组织和连接性。因此，这种制备方法可能是一个有用的模型，可用于进行进一步研究，以探究所代表结构之间的功能回路。
