Molinari M, Dell'Anna M E, Rausell E, Leggio M G, Hashikawa T, Jones E G
Institute of Physical and Chemical Research, RIKEN, Saitama, Japan.
J Comp Neurol. 1995 Nov 13;362(2):171-94. doi: 10.1002/cne.903620203.
This study investigated differentiation of Macaca fuscata auditory thalamus into chemically defined nuclei forming relays to auditory cortical areas. The thalamus was stained immunocytochemically for parvalbumin and 28 kDa calbindin in normals and in brains in which retrogradely transported tracers were injected into middle layers of auditory cortical areas or applied to the cortical surface. Parvalbumin- and calbindin-immunoreactive cells show a complementary distribution in ventral, anterodorsal, posterodorsal, and magnocellular medial geniculate nuclei. The ventral nucleus has a high density of parvalbumin cells and few calbindin cells, and the anterodorsal nucleus has a high density of parvalbumin cells and moderate numbers of calbindin cells. Both nuclei have a dense parvalbumin-immunoreactive neuropil formed by terminations of fibers ascending in the brachium of the inferior colliculus. The posterodorsal nucleus has approximately equal proportions of parvalbumin and calbindin cells; neuropil staining is weak but contains terminations of calbindin-immunoreactive fibers ascending in the midbrain tegmentum. The magnocellular nucleus contains domains of parvalbumin and calbindin cells. Parvalbumin cells in the ventral nucleus project to a central core of auditory cortex with densest parvalbumin immunoreactivity. Those in anterodorsal and posterodorsal nuclei project to surrounding auditory fields with less dense parvalbumin immunoreactivity; those in the magnocellular nucleus project widely to auditory and other fields. Injections of middle cortical layers label a large majority of parvalbumin cells in the ventral, anterodorsal, or posterodorsal nuclei and in the magnocellular nucleus. Superficial deposits label calbindin cells only, usually in more than one nucleus, implying a widespread projection system.
本研究调查了猕猴听觉丘脑分化为化学定义的核团，这些核团形成通向听觉皮层区域的中继站。对正常猕猴以及将逆行运输示踪剂注入听觉皮层区域中层或应用于皮层表面的大脑，进行免疫细胞化学染色，检测丘脑中小清蛋白和28 kDa钙结合蛋白。小清蛋白和钙结合蛋白免疫反应性细胞在腹侧、前背侧、后背侧和大细胞内侧膝状核中呈互补分布。腹侧核中小清蛋白细胞密度高，钙结合蛋白细胞少；前背侧核中小清蛋白细胞密度高，钙结合蛋白细胞数量中等。这两个核团都有由下丘臂中上行纤维终末形成的密集小清蛋白免疫反应性神经毡。后背侧核中小清蛋白和钙结合蛋白细胞比例大致相等；神经毡染色较弱，但含有中脑被盖中上行的钙结合蛋白免疫反应性纤维的终末。大细胞核包含小清蛋白和钙结合蛋白细胞区域。腹侧核中的小清蛋白细胞投射到听觉皮层的中央核心，小清蛋白免疫反应性最强。前背侧和后背侧核中的小清蛋白细胞投射到周围听觉区域，小清蛋白免疫反应性较弱；大细胞核中的小清蛋白细胞广泛投射到听觉和其他区域。注入皮层中层标记腹侧、前背侧或后背侧核以及大细胞核中的大部分小清蛋白细胞。表面沉积仅标记钙结合蛋白细胞，通常在不止一个核中，这意味着存在广泛的投射系统。
