Christensen M K, Geneser F A
Department of Neurobiology, University of Aarhus, Denmark.
Anat Embryol (Berl). 1995 Mar;191(3):227-37. doi: 10.1007/BF00187821.
The present study describes the distribution of neurons of origin of zinc-containing pathways in the amygdaloid complex of the rat, using the selenium method for simultaneous retrograde labeling of all zinc-containing neurons. With this method, vesicular ionic zinc is precipitated intravitally with selenium compounds and transported retrogradely to the parent neurons, where it can be visualized by silver amplification. Neurons labeled retrogradely with silver-amplified precipitate were observed in all amygdaloid nuclei except for the lateral olfactory tract nucleus, the accessory olfactory tract nucleus and the central nucleus. Very few labeled cell bodies were seen in the anterior amygdaloid area and the medial nucleus. The amygdalo-hippocampal area and the amygdalo-piriform transition area both showed a substantial number of labeled somata throughout their rostrocaudal extent. In the anterior cortical nucleus, very few labeled cell bodies were found in the rostral pole, whereas they were abundant in the caudal quarter of the nucleus. In the posterolateral cortical nucleus, the number of labeled cell bodies increased gradually; there were none in the rostral pole, but most of the neurons in the caudal part were labeled. The posteromedial cortical nucleus contained a great number of labeled somata, but with some variation in the rostrocaudal extent of the nucleus. Considerable numbers of labeled neurons were observed throughout the lateral nucleus. In the basolateral nucleus, a small number of labeled cell bodies was present in the rostral half, but a gradual increase was observed in the caudal direction. Finally, in the basomedial nucleus, very few labeled cell bodies were present in the rostral two-thirds, whilst a considerable number was encountered in the caudal one-third. Possible functional implications of neuronal zinc are considered. The distribution of neurons of origin of zinc-containing projections has been compared with previously described intrinsic connections of the rat amygdala, and tracts that may possibly be zinc-containing are outlined and discussed. It is concluded that in all probability a substantial proportion of the intrinsic connectivity of the rat amygdaloid complex is zinc-containing.
本研究采用硒法对大鼠杏仁复合体中含锌通路的起始神经元进行同步逆行标记，描述了这些神经元的分布情况。通过这种方法，囊泡离子锌在活体中与硒化合物沉淀，并逆行运输到其起始神经元，在那里可以通过银增强法进行可视化。除外侧嗅束核、副嗅束核和中央核外，在所有杏仁核中均观察到经银增强沉淀逆行标记的神经元。在杏仁前区和内侧核中可见到极少数标记的细胞体。杏仁海马区和杏仁梨状过渡区在其整个前后范围内均显示出大量标记的胞体。在前皮质核中，在吻端极少发现标记的细胞体，而在核的尾侧四分之一区域则大量存在。在后外侧皮质核中，标记细胞体的数量逐渐增加；吻端没有，而尾侧部分的大多数神经元都被标记。后内侧皮质核包含大量标记的胞体，但在核的前后范围内存在一些差异。在整个外侧核中观察到相当数量的标记神经元。在基底外侧核中，在吻侧半部存在少量标记的细胞体，但在尾侧方向观察到逐渐增加。最后，在基底内侧核中，在吻侧三分之二区域极少存在标记的细胞体，而在尾侧三分之一区域则遇到相当数量的标记细胞体。文中考虑了神经元锌可能的功能意义。已将含锌投射起始神经元的分布与先前描述的大鼠杏仁核的内在连接进行了比较，并概述和讨论了可能含锌的纤维束。得出的结论是，大鼠杏仁复合体的内在连接很可能有很大一部分是含锌的。
