Distribution of synapses on identified cell types in a gustatory subdivision of the nucleus of the solitary tract.
Distribution of synapses on identified cell types in a gustatory subdivision of the nucleus of the solitary tract.
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孤束核味觉细分中已识别细胞类型的突触分布。
DOI：
10.1002/cne.903320306
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Whitehead,MC
中科院分区：
文献类型：
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作者：
Whitehead,MC
仓鼠孤束嘴侧核（NST）内两种形态的神经元向臂旁核（PBN）发出轴突。长形细胞有椭圆形的胞体和2个向中间外侧的初级树突。大的星状细胞有多边形的胞体和3-5个放射状的初级树突。这两种细胞类型都位于NST的吻侧中央亚部，被来自口腔的初级传入轴突包围。本研究用电子显微镜观察了辣根过氧化物酶（HRP）标记的PBN投射细胞的突触输入。标记细胞上的突触主要由三种轴突终末构成。初级样终末包含大的、清晰的、圆形的囊泡，并参与不对称的突触连接;它们类似于先前鉴定的味觉（面部）传入终末（Whitehead，J. Comp. Neurol. 244：72，1986）。轴突终端含有小，多形性小泡（SP终端），形成对称的交界处，并类似于高尔基体II结束。含有中等大小多形性囊泡（MP终末）的终末形成不对称连接。这些类型的轴突终末在标记细胞上的分布差异。初级样输入主要限于远端树突及其棘。SP终末比初级样或MP终末提供更多的突触覆盖;对于这两种细胞类型，SP输入集中在树突和细胞体的近端。这些数据表明，细长和大的星状细胞作为二级投射神经元在上行味觉系统中发挥作用。不同类型突触的密度、空间分布和激活时间可能与投射神经元的电生理反应特性有关。© 1993 Wiley利斯公司
Two morphological types of neurons in the rostral nucleus of the solitary tract (NST) in the hamster send axons to the parabrachial nucleus (PBN). Elongate cells have oval cell bodies and 2 mediolaterally oriented primary dendrites. Large stellate cells have polygonal cell bodies and 3–5 radiating primary dendrites. Both cell types are located in the rostral central subdivision of the NST, surrounded by primary afferent axons from the oral cavity. This study uses electron microscopy to evaluate the synaptic inputs to horseradish peroxidase (HRP)‐labelled elongate and stellate PBN projection cells.Three types of axon terminals provide most of the synapses on the labelled cells. Primary‐like terminals contain large, clear, round vesicles and engage in asymmetrical synaptic junctions; they resemble gustatory (facial) afferent terminals identified previously (Whitehead, J. Comp. Neurol. 244:72, 1986). Axon terminals containing small, pleomorphic vesicles (SP terminals), form symmetrical junctions, and resemble Golgi II endings. Terminals containing medium‐sized pleomorphic vesicles (MP terminals) form asymmetrical junctions. These types of axon terminals distribute differentially on the labelled cells. Primary‐like inputs are largely restricted to distal dendrites and their spines. SP terminals provide more synaptic coverage than primary‐like or MP terminals; for both cell types the SP inputs are concentrated proximally on dendrites and cell bodies. The data suggest that elongate and large stellate cells function as second‐order projection neurons in the ascending taste system. The density, spatial distribution, and timing of activation of the various types of synapses could relate to the electrophysiological response properties of the projection neurons. © 1993 Wiley‐Liss, Inc.