McDonald J K, Parnavelas J G, Davies S W, Cavanagh M E
Department of Anatomy and Cell Biology, Emory University School of Medicine, Atlanta, Georgia 30322.
Exp Neurol. 1993 Oct;123(2):216-21. doi: 10.1006/exnr.1993.1154.
The levels of somatostatin and neuropeptide Y were measured with radioimmunoassay bilaterally in visual cortical areas 17, 18, and 18a of rats which had received monocular enucleation at birth. Neuropeptide levels were consistently three- to fourfold higher for neuropeptide Y than for somatostatin. Monocular enucleation did not change somatostatin levels within areas 17 or 18 of either hemisphere but significantly increased somatostatin levels in contralateral area 18a when compared to contralateral areas 17 or 18 3 months after enucleation. The concentrations of neuropeptide Y are significantly greater in areas 17 and 18a than those in area 18, however, neonatal enucleation had no significant effect on neuropeptide Y levels within any visual cortical area of either hemisphere. Visual cortical areas 17, 18, and 18a show differences in the relative concentrations of neuropeptide Y compared to somatostatin. Furthermore, these two peptides respond distinctively to neonatal enucleation. Enucleation had no effect on the concentration of either peptide in samples of frontal cortex. Immunohistochemical analysis showed that area 17 contains far fewer somatostatin neurons than areas 18 or 18a, in marked contrast to the uniform levels of somatostatin measured in all visual cortical areas by radioimmunoassay. Immunohistochemically identified neuropeptide Y-immunoreactive neurons are evenly distributed between areas 17, 18, and 18a and represent about half of the number of somatostatin-immunoreactive cells. While neuropeptide Y levels are significantly different between these visual cortical areas, the numbers of immunoreactive neurons are similar. Thus, relatively few neuropeptide Y cells are accompanied four- to fivefold higher than those for somatostatin, the more abundant cell type.(ABSTRACT TRUNCATED AT 250 WORDS)
采用放射免疫分析法双侧检测出生时即接受单眼摘除的大鼠视觉皮层17区、18区和18a区生长抑素和神经肽Y的水平。神经肽Y的水平始终比生长抑素高3至4倍。单眼摘除并未改变任一脑半球17区或18区内的生长抑素水平，但与摘除后3个月时对侧的17区或18区相比，对侧18a区的生长抑素水平显著升高。然而，17区和18a区神经肽Y的浓度明显高于18区，不过，新生期摘除对任一脑半球的任何视觉皮层区内神经肽Y的水平均无显著影响。与生长抑素相比，视觉皮层17区、18区和18a区神经肽Y的相对浓度存在差异。此外，这两种肽对新生期摘除的反应截然不同。摘除对额叶皮层样本中任一肽的浓度均无影响。免疫组织化学分析显示，与放射免疫分析法在所有视觉皮层区测得的生长抑素均匀水平形成鲜明对比的是，17区含有的生长抑素神经元远少于18区或18a区。免疫组织化学鉴定的神经肽Y免疫反应性神经元在17区、18区和18a区之间均匀分布，约占生长抑素免疫反应性细胞数量的一半。虽然这些视觉皮层区之间神经肽Y的水平存在显著差异，但免疫反应性神经元的数量相似。因此，相对较少的神经肽Y细胞伴随的（浓度）比生长抑素这种更丰富的细胞类型高4至5倍。（摘要截选至250词）
