The mophology of the Koniocellular axon pathway in the macaque monkey
The mophology of the Koniocellular axon pathway in the macaque monkey
复制标题
DOI：
10.1093/cercor/bhl142
复制
发表时间：
2007-10-01
期刊：
影响因子：
3.7
通讯作者：
Ding, Y.
中科院分区：
文献类型：
--
作者：
Casagrande, V. A.;Yazar, F.;Ding, Y.
本研究的主要目的是确定猕猴初级视皮层（V1）内外侧膝状体（LGN）轴突的分布和形态。特别是，我们有兴趣了解K轴突的亚群是否存在于这个物种中，如果是这样，如果这些亚群来自不同的K层的LGN。限制注射示踪剂，生物素化葡聚糖胺，或菜豆白细胞凝集素有针对性的特定LGN K层的电生理指导下和免疫细胞化学被用来可视化标记的轴突在皮质，随后重建通过连续切片。共重建了36个完整的轴突和166个轴突节段。我们的研究结果确定了至少2个主要亚群的K轴突在猕猴V1的分支模式和终扣分布的基础上。主要来自LGN层K1和K2的轴突在形态上是简单的，并且倾向于在皮质层1和3A中分支。这些轴突产生比在从背侧K LGN层K3-K6产生的轴突中看到的更少的终扣。从LGN层K3-K6产生的轴突终止于层3B α中的细胞色素氧化酶（CO）斑点中的复杂的、集中的乔木，仅偶尔有简单的投射到皮层的更表层。结合以前的观察，我们的数据表明，猕猴的K LGN轴突至少有3个亚类，它们与先前在两种夜行猴中发现的K轴突相似（Ding和Casagrande 1997）和在原猴亚目中，丛猴（Lachica和Casagrande，1992）这表明终止于CO斑点和第1层的LGN K通道不是猕猴所独有的，而是灵长类动物的共同特征。
The key objective of this study was to determine the distribution and morphology of koniocellular (K) lateral geniculate nucleus (LGN) axons in primary visual cortex (V1) of the macaque monkey. In particular, we were interested in understanding whether subpopulations of K axons exist in this species and, if so, if these subpopulations arise from different K layers of the LGN. Restricted injections of the tracers, biotinilated dextran amine, or Phaseolus vulgaris leucoagglutinin were targeted to specific LGN K layers under electrophysiological guidance and immunocytochernistry was used to visualize labeled axons in cortex that were subsequently reconstructed through serial sections. A total of 36 complete axons and 166 axon segments were reconstructed. Our results identified at least 2 main subpopulations of K axons in macaque V1 based on branching patterns and bouton distribution. Axons that arise primarily from LGN layers K1 and K2 are morphologically simple and tend to branch in cortical layers 1 and 3A. These axons give rise to fewer boutons than seen in axons arising from the dorsal K LGN layers K3-K6. Axons that arise from LGN layers K3-K6 terminate as complex, focused arbors in the cytochrome oxidase (CO) blobs in layer 3B alpha, with only occasional simple projections to the more superficial layers of cortex. Combined with previous observations, our data suggest that there are at least 3 subclasses of K LGN axons in macaque monkey that are similar to K axons identified earlier in both nocturnal simian owl monkeys (Ding and Casagrande 1997) and in prosimian, bush babies (Lachica and Casagrande 1992) suggesting that the LGN K channels that terminate in the CO blobs and in layer 1 are not unique to macaque monkeys but are a common primate feature.