Differential expression of acetylcholinesterase in the developing barrel cortex of three rodent species.
Differential expression of acetylcholinesterase in the developing barrel cortex of three rodent species.
复制标题
三种啮齿类动物发育中的桶状皮层中乙酰胆碱酯酶的差异表达。
DOI：
10.1093/cercor/6.3.377
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Jhaveri,S
中科院分区：
文献类型：
--
作者：
Sendemir,E;Erzurumlu,RS;Jhaveri,S
乙酰胆碱酯酶（AChE）在一些未成熟的轴突系统中短暂表达。它在发展丘脑皮质传入事件中的存在导致使用酶组织化学来可视化大鼠的轴突系统。因为酶在大鼠大脑皮层的时空分布。有人认为乙酰胆碱酯酶在丘脑皮质连接的建立中起作用。我们在这里表明，与小鼠和仓鼠相比，AChE在大鼠的SI皮质中的分布模式明显不同。在大鼠幼崽中，出生后不久，富含痛觉的斑块以与触电相关的阵列分布在SI皮质中，而位于单个斑块之间和斑块之间的皮质区域则缺乏这种酶。相比之下。PND3和老年小鼠及仓鼠的扁平皮质切片显示，桶核中心有轻度染色的AChE阳性斑点，而桶壁仍然没有AChE；分隔单个木桶的隔层酶阳性。这三种酶的层状定位差异也很明显。在出生后大鼠的丘脑中，腹侧后内侧核（VPM）和腹侧后外侧核（VPL）都表达AChE，这与整个桶区皮层中含有酶的斑块的存在有关。然而，在另外两种啮齿类动物中，这种酶存在于VPL而不存在于VPM，尽管在这些物种中，与两个丘脑核相关的皮质桶中几乎没有这种酶。因此，乙酰胆碱酯酶在丘脑腹基底复合体核内的分布与其皮层轴突末端在桶区存在的关系在不同啮齿类动物中并不一致。我们的研究结果呼吁在使用乙酰胆碱酯酶组织化学作为未成熟丘脑皮质轴突的普遍标记时要谨慎，并挑战目前这种瞬时表达酶在啮齿动物丘脑皮质投射发育过程中普遍存在的假设作用。
Acetylcholinesterase (AChE) is transiently expressed in several immature axon systems. Its presence in developing thalamocortical afferents has led to the use of enzyme histochemistry to visualize this axon system in rats. Because of the spatiotemporal distribution of the enzyme in the rat neocortex. it has been suggested that AChE plays a role in the establishment of thalamocortical connectivity.We show here that AChE is distributed in a pattern that is markedly different in SI cortex of rats as compared to that of mice and hamsters. In rat pups, AChE-rich patches are distributed in a vibrissa-related array in the SI cortex soon after birth, whereas regions of cortex that lie between individual patches, and between rows of patches, are impoverished in the enzyme. In contrast. sections through flattened cortices from PND3 and older mice and hamsters reveal lightly stained, AChE-positive spots in the center of barrel cores, while barrel walls remain devoid of AChE; septae that divide individual barrels are densely enzyme positive. Differences in laminar localization of the enzyme for all three species are also visible.In the thalamus of postnatal rats, both the ventral posterior medial (VPM) and ventral posterior lateral (VPL) nuclei express AChE, correlating with the presence of enzyme-containing patches throughout the barrelfield cortex. In the other two rodents, however, the enzyme is present in VPL but not in VPM, despite the fact that in these species the cortical barrels associated with both thalamic nuclei have very little of the enzyme. Thus, the relationship between the distribution of AChE in nuclei of the thalamic ventrobasal complex and the presence of AChE in the terminals of their cortical axons in the barrelfield is not consistent across different rodent species.Our results call for caution in the use of AChE histochemistry as a universal marker for immature thalamocortical axons, and challenge the generality of currently hypothesized roles for this transiently expressed enzyme during the development of the rodent thalamocortical projection.