Studies on developing and transplanted monoaminergic neurons using an "ultra-thin" slice preparation

使用“超薄”切片制剂开发和移植单胺能神经元的研究

• 批准号: 02670054
• 负责人: MATSUDA Yoshihiro
• 金额: $ 1.41万
• 依托单位: Nagasaki University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02670054/
• 关键词: Brain stem; Monoaminergic neurons; Slice preparation; Fluorescent marker; Functional maturation; アミン性細胞; スライス標本; 脳内細胞移植

An attempt was made to identify living monoaminergic neurons for electrophysiology in a brain slice preparation in the hope that the procedure would enable to study the sequence of events which might occur in the course of functional maturation of developing an transplanted monoaminergic neurons. Thin (80-100 mu thick) brain-stem slices obtained from young rats (5-25 days old) were treated with a serotonin analogue, 5, 7-dihydroxytryptamine (5, 7-DHT). Neurons accumulating the substance fluoresced under ultraviolet light. The localization of labelled cells in the raphe nuclei suggested that they were serotonerigc neurons. No cells were labelled in the dopamine neuron-containing substantia nigra. Intracellular recording also revealed that the responsed of labelled neurons conformed to those reported for serotonergic raphe neurons ; the spike potential of the neurons was slow in time course, showing a hump on its falling phase, and their membrane time constant was long. Application of 5, 7-DHT slightly broadened the spike width and depressed the transient outward rectification of the labelled neurons, but the neurons were still identifiable by their pattern of responses.The time course of maturation of sprotonergic raphe neurons was studied using the above-mentioned procedure. The neurons showed the main traits of their character even at the early postnatal periods. The data, along with those obtained from dopaminergic nigral neurons, suggested that brain-stem monoaminergic neurons were functionally fairly mature at birth, although further 2 weeks seemed to be necessary for their full matumration. Concerning the changes in property of monoaminergic neurons transplanted in vivo, definitive results have not yet been obtained and further studies are needed.

尝试在脑切片制备中鉴定用于电生理学的活的单胺能神经元，希望该程序能够研究在移植的单胺能神经元发育的功能成熟过程中可能发生的事件的顺序。用5-羟色胺类似物5，7-二羟色胺（5，7-DHT）处理从年轻大鼠（5-25日龄）获得的薄（80-100 μ厚）脑干切片。积聚这种物质的神经元在紫外线下发出荧光。标记细胞定位于中缝核，表明它们是神经元。在含有多巴胺神经元的黑质中没有细胞被标记。细胞内记录还显示，标记神经元的反应与已报道的中缝核能神经元的反应一致，其峰电位时程缓慢，下降相呈驼峰状，膜时间常数较长。应用5，7-二氢睾酮（5，7-DHT）可使标记神经元的峰宽稍增宽，瞬时外向整流减弱，但仍能从反应方式上辨认。即使在出生后的早期，神经元也表现出其性格的主要特征。这些数据，沿着从多巴胺能黑质神经元获得的数据，表明脑干单胺能神经元在出生时功能相当成熟，尽管它们的完全成熟似乎还需要2周。关于单胺能神经元移植后的性质变化，目前还没有明确的结果，需要进一步的研究。