Hendry S H, Bhandari M A
Department of Anatomy and Neurobiology, University of California, Irvine 92717.
Vis Neurosci. 1992 Nov;9(5):445-59. doi: 10.1017/s0952523800011251.
Immunocytochemical staining for microtubule-associated protein 2 (MAP 2) was used to examine the morphology of neurons, the organization of neuronal groups, and the neurochemical plasticity of cells in adult monkey area 17. MAP 2-immunostained neurons are present through the depth of area 17 but are most intensely immunoreactive in layers IVB and VI. From layer IVB, separate groups of MAP 2-positive cells invade layers IVA and IVC alpha. Clusters of cells protrude upward from superficial layer IVB and occupy the central core regions of the cytochrome oxidase (CO)-stained honeycomb in layer IVA, while large neurons typical of layer IVB are distributed in irregular clusters in the subjacent layer IVC alpha. The somata in the layer IVA honeycomb cores give off immunostained dendrites which remain largely within the core regions. Patches of MAP 2-positive neurons are also present in layers II and III, where they coincide with the CO-stained puffs. Intravitreal injections of tetrodotoxin (TTX) into one eye of adult monkeys produce stripes of alternating light and dark MAP 2 immunostaining in layer IVC. Stripes of light immunostaining coincide with stripes of light CO staining, and correspond to reduced MAP 2 immunoreactivity within cortical neurons dominated by the TTX-injected eye. In layers II and III, the MAP 2 immunostaining of patches overlying the injected-eye columns is similarly reduced. No change occurs in the MAP 2 immunostaining of layer IVA. These data suggest that the anatomical and physiological heterogeneity of layers IVA and IVC alpha arises from the periodic invasion of neurons characteristic of layer IVB, that the neurons in layer IVA have dendrites confined to thalamocortical-recipient or nonrecipient zones and that the expression of MAP 2 changes in adult cortical neurons following the loss of retinal input.
采用微管相关蛋白2（MAP 2）免疫细胞化学染色法，研究成年猴17区神经元的形态、神经元群的组织以及细胞的神经化学可塑性。MAP 2免疫染色的神经元贯穿17区的各层，但在IVB层和VI层免疫反应最为强烈。从IVB层开始，不同的MAP 2阳性细胞群侵入IVA层和IVCα层。细胞簇从表层IVB向上突出，占据IVA层细胞色素氧化酶（CO）染色的蜂窝状结构的中心核心区域，而IVB层典型的大神经元则不规则地分布在相邻的IVCα层。IVA层蜂窝状核心区域的胞体发出免疫染色的树突，这些树突大多保留在核心区域内。II层和III层也存在MAP 2阳性神经元斑块，它们与CO染色的隆起区域重合。向成年猴的一只眼玻璃体内注射河豚毒素（TTX），会在IVC层产生明暗交替的MAP 2免疫染色条纹。浅色免疫染色条纹与浅色CO染色条纹重合，对应于注射TTX的眼睛所支配的皮质神经元内MAP 2免疫反应性降低。在II层和III层，覆盖注射眼柱的斑块的MAP 2免疫染色也同样降低。IVA层的MAP 2免疫染色没有变化。这些数据表明，IVA层和IVCα层的解剖学和生理学异质性源于IVB层特征性神经元的周期性侵入；IVA层的神经元树突局限于丘脑皮质接受区或非接受区；视网膜输入丧失后，成年皮质神经元中MAP 2的表达发生变化。
