Vercelli A E, Cracco C M
Department of Human Anatomy and Physiology, School of Medicine, University of Torino, Italy.
Brain Res Dev Brain Res. 1994 Nov 18;83(1):85-98. doi: 10.1016/0165-3806(94)90182-1.
Dihydronicotinamide adenine-dinucleotide phosphate diaphorase (NADPH-d) positive neurons in the superficial layers of superior colliculus (SC) were studied in the adult rat after eye enucleation at postnatal day 5 (P5). Bilaterally, NADPH-d histochemistry revealed either weakly or intensely labeled neurons. In the SC contralateral to the enucleation, the volume of superficial layers decreased significantly, whereas the total number of NADPH-d positive neurons was only slightly reduced, thus resulting in an increased cell density. Bilaterally, the number of NADPH-d positive neurons was around 20% of Nissl-stained neurons. While the number of neurons which were weakly positive for NADPH-d was unchanged contralateral to the enucleation (thus resulting in a significant increase in their percentage on the overall NADPH-d population), the number of intensely labeled neurons decreased by 30%. Intensely labeled neurons were classified with respect to cell size and dendritic distribution. Some (126) were reconstructed and analyzed on the computer, in order to quantitate morphological differences in dendritic distribution in the denervated and control SC. The percent of neurons which could be assigned to some classes (marginal, stellate, narrow field vertical and wide field vertical) was reduced contralateral to the enucleation. In addition, vertically-oriented neurons (narrow field vertical, wide field vertical and pyriform) showed a significant decrease in soma size, dendritic length and number of branch points. And finally, the overall orientation of dendrites on narrow and wide field vertical neurons was more dispersed, when compared to the control colliculus. Thus, P5 eye enucleation affects the adult morphology of NADPH-d positive neurons in the superficial layers of the rat SC, resulting in increased cell density, changed relative number of cells in each morphological type, and altered soma size, dendritic length and orientation in specific neurons.
在出生后第5天（P5）摘除眼球的成年大鼠中，研究了上丘（SC）浅层的二氢烟酰胺腺嘌呤二核苷酸磷酸黄递酶（NADPH-d）阳性神经元。双侧NADPH-d组织化学显示神经元标记较弱或较强。在摘除眼球对侧的SC中，浅层体积显著减小，而NADPH-d阳性神经元总数仅略有减少，从而导致细胞密度增加。双侧NADPH-d阳性神经元数量约为尼氏染色神经元数量的20%。虽然摘除眼球对侧NADPH-d弱阳性神经元数量未变（因此其在整个NADPH-d阳性神经元群体中的百分比显著增加），但强标记神经元数量减少了30%。根据细胞大小和树突分布对强标记神经元进行分类。对其中一些神经元（126个）进行了计算机重建和分析，以量化去神经支配侧和对照侧SC中树突分布的形态学差异。摘除眼球对侧可归为某些类型（边缘型、星型、窄野垂直型和宽野垂直型）的神经元百分比降低。此外，垂直定向的神经元（窄野垂直型、宽野垂直型和梨形）的胞体大小、树突长度和分支点数显著减少。最后，与对照上丘相比，窄野和宽野垂直神经元的树突总体取向更加分散。因此，P5期摘除眼球影响大鼠SC浅层NADPH-d阳性神经元的成年形态，导致细胞密度增加、各形态类型细胞相对数量改变以及特定神经元的胞体大小、树突长度和取向改变。
