Mook Jo Seung, Kuk Kim Yong, Wang Zhanyou, Danscher Gorm
Department of Anatomy, Hallym University, Okchon-1-Dong, Chunchon 200-702, South Korea.
Brain Res. 2002 Nov 29;956(2):230-5. doi: 10.1016/s0006-8993(02)03544-8.
Zinc ions seem to be important to several neurological functions and have been connected to the pathophysiology of epilepsy, neuronal cell death after seizure or stroke, and Alzheimer's disease. Both epilepsy and Alzheimer's disease are clinical conditions believed to involve the olfactory bulb. The mammalian olfactory bulb is densely innervated by zinc-enriched (ZEN) neurons, and the distribution of the ZEN terminals in the mouse olfactory bulb has previously been described. The aim of this study was to describe the origins of ZEN terminals projecting into the main olfactory bulb of the rat. Selective labeling of ZEN terminals was accomplished by intracerebral infusion of sodium selenide, whereby zinc selenium clusters are created in the ZEN terminals. Some of these clusters move by retrograde axonal transport to the somata where they can be silver-enhanced by autometallography (AMG). After infusion of sodium selenide into the main olfactory bulb, retrogradely labeled ZEN somata were found (1) ipsilaterally in all anterior olfactory nuclei, taenia tecta, piriform cortex and lateral entorhinal cortex, and (2) contralaterally in anterior olfactory nuclei except the external division. The ipsilateral anterior olfactory nucleus had the densest population of ZEN somata, and it was found that these somata originated mainly from pyramidal neurons in layers II and III of each area. The olfactory-related centrifugal afferents to the main olfactory bulb are discussed.
锌离子似乎对多种神经功能很重要，并且与癫痫、癫痫发作或中风后神经元细胞死亡以及阿尔茨海默病的病理生理学有关。癫痫和阿尔茨海默病都是被认为涉及嗅球的临床病症。哺乳动物的嗅球由富含锌的（ZEN）神经元密集支配，并且之前已经描述了ZEN终末在小鼠嗅球中的分布。本研究的目的是描述投射到大鼠主嗅球的ZEN终末的起源。通过向脑内注入硒化钠来实现对ZEN终末的选择性标记，由此在ZEN终末中形成锌硒簇。其中一些簇通过逆行轴突运输移动到胞体，在那里它们可以通过自动金属显影术（AMG）进行银增强。在将硒化钠注入主嗅球后，发现了逆行标记的ZEN胞体：（1）在同侧的所有前嗅核、带状皮层、梨状皮层和外侧内嗅皮层中，以及（2）在对侧除外侧部之外的前嗅核中。同侧前嗅核中ZEN胞体的数量最密集，并且发现这些胞体主要起源于每个区域II层和III层的锥体细胞。讨论了对主嗅球的嗅觉相关离心传入纤维。
