Berk M L
Department of Anatomy, Marshall University School of Medicine, Huntington, West Virginia 25755-9350.
J Comp Neurol. 1991 Oct 15;312(3):391-403. doi: 10.1002/cne.903120307.
The avian nucleus of the solitary tract has an extensive subnuclear organization. Several subnuclear cell groups can be distinguished on the basis of cytoarchitectonic criteria. In general, the subnuclei of the medial division of the nucleus of the solitary tract receive gastrointestinal afferents, whereas the subnuclei of the lateral division of the nucleus of the solitary tract receive cardiopulmonary afferents. Forebrain afferents to the nucleus of the solitary tract are segregated to medial and lateral subnuclei, which are located at the periphery of the nucleus. These peripheral subnuclei of the nucleus of the solitary tract are also the source of ascending axonal projections to the forebrain. In this study, the tyrosine hydroxylase (initial enzyme for catecholamine synthesis) content of the anteromedial hypothalamic projecting neurons of the nucleus of the solitary tract is determined by use of a combined retrograde fluorescent dye-immunofluorescence method. Fast Blue implanted into the anteromedial hypothalamus (in the region of the nucleus periventricularis magnocellularis) resulted in the retrograde labeling of neurons in the caudal two-thirds of the nucleus of the solitary tract. At levels rostral to the obex, dye-labeled cells were mostly observed in the dorsally located subnuclei medialis superficialis pars posterior and lateralis dorsalis pars posterior and in the ventrally located subnucleus medialis ventralis pars posterior. More centrally located subnuclei contained few labeled cells, if any. For example, subnucleus medialis intermedius pars posterior only had a few retrogradely labeled cells, whereas the centrally located subnucleus medialis dorsalis pars posterior was almost devoid of labeled cells. At levels caudal to the obex, many retrogradely labeled neurons of the nucleus of the solitary tract were observed. Neurons immunoreactively labeled for tyrosine hydroxylase were mostly found within subnuclei, which contain anteromedial hypothalamic projection neurons. In subnuclei medialis superficialis pars posterior and lateralis dorsalis pars posterior, 87% of the retrogradely dye-labeled cells were also immunoreactively labeled, whereas in the caudal nucleus of the solitary tract (at levels caudal to the obex), 68% of the retrogradely labeled cells were immunoreactively labeled. Not all tyrosine hydroxylase containing cells had projections to the implantation site in the anteromedial hypothalamus since only 40% of the immunoreactive cells in the caudal nucleus of the solitary tract and 59% of the immunoreactive cells in the subnucleus medialis superficialis pars posterior were retrogradely labeled with Fast Blue.(ABSTRACT TRUNCATED AT 400 WORDS)
禽类孤束核具有广泛的亚核组织。根据细胞构筑标准可区分出几个亚核细胞群。一般来说，孤束核内侧部的亚核接收胃肠道传入纤维，而孤束核外侧部的亚核接收心肺传入纤维。孤束核的前脑传入纤维被分隔到位于核周边的内侧和外侧亚核。孤束核的这些周边亚核也是向前脑投射的轴突的来源。在本研究中，使用逆行荧光染料 - 免疫荧光联合方法测定孤束核下丘脑前内侧投射神经元的酪氨酸羟化酶（儿茶酚胺合成的起始酶）含量。将快蓝植入下丘脑前内侧（在室旁大细胞核区域）导致孤束核尾侧三分之二的神经元逆行标记。在闩前方的水平，染料标记的细胞大多见于背侧的浅表内侧亚核后部和背侧外侧亚核后部以及腹侧的内侧腹侧亚核后部。更位于中央的亚核含有的标记细胞很少，甚至没有。例如，内侧中间亚核后部只有少数逆行标记细胞，而位于中央的内侧背侧亚核后部几乎没有标记细胞。在闩后方的水平，观察到许多孤束核的逆行标记神经元。免疫反应性标记酪氨酸羟化酶的神经元大多见于含有下丘脑前内侧投射神经元的亚核内。在浅表内侧亚核后部和背侧外侧亚核后部，87％的逆行染料标记细胞也被免疫反应性标记，而在孤束核尾侧核（在闩后方的水平），68％的逆行标记细胞被免疫反应性标记。并非所有含酪氨酸羟化酶的细胞都向前内侧下丘脑的植入部位投射，因为孤束核尾侧核中只有40％的免疫反应性细胞和浅表内侧亚核后部中59％的免疫反应性细胞被快蓝逆行标记。（摘要截短于400字）
