Regulatory Mechanism of Synthesis of Peptides and Receptors in Motoneurons : in Situ Hybridization Study

运动神经元肽和受体合成的调控机制：原位杂交研究

基本信息

批准号：
01570027
负责人：
SENBA Emiko
金额：
$ 1.34万
依托单位：
Osaka 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：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01570027/
关键词：
Motoneuron Axotomy In Situ Hybridization Galanin CCK CGRP Neuronal Hicotinic Ach Receptor NGF receptor αーCGRP βーCGRP in situ ハイブリダイゼ-ション NGF リセプタ-axotomy(軸索切断)ペプタイド NGFーリセプタ-アセチルコリン・リセプタ-mRNA

项目摘要

Acetylcholine (Ach) has been a sole candidate of neurotransmitter in motoneurons for a long time. Recent advance of molecular biology and applied morphological techniques have revealed the presence of neuropeptides in moto-neurons. These peptides are considered to modulate the activity of moto-neurons and muscles, or exert neurotrophic effects on them. In addition to peptides, neurotransmitter receptors are also synthesized in moto-neurons indicating that various kinds of neurotransmitters regulate the activity of motoneurons. Moreover, motoneurons are under the control of neurotrophic factors, such as nerve growth factor (NGF). It has been demonstrated that both NGF-receptor mRNA and NGF-receptor protein are expressed in developing motoneurons, and also in mature motoneurons under some experimental conditions. In the present study, we employed in situ hybridization histochemistry to demonstrate how the production of these peptides and receptors are regulated in injured motoーneurons.It … More is well documented that calcitonin gene-related peptide (CGRP)-like immunoreactivity in motoneurons of the rat spinal cord is increased after peripheral axotomy. In these neurons, axotomy caused the increase of alpha -CGRP mRNA, but not beta -CGRP mRNA, indicating that alpha -CGRP and beta -CGRP are regulated independently and have different roles in motoneurons. We have also shown that alpha - and beta -subunits constructing neuronal nicotinic Ach receptor are also differentially regulated in motoneurons. alpha 3 and beta 2 subunit mRNAs were expressed in 12% and 40% of facial motoneurons of the rat. alpha 3 subunit mRNA signals disappeared in response to axotomy, whereas the beta 2 subunit mRNA signal was remarkably enhanced.Some 38%, 55% and 7% of the facial motoneurons of the rat expressed alpha -CGRP, beta -CGRP and CCK mRNAs, respectively. No galanin mRNA containing motoneurons were observed. The levels of mRNA for alpha -CGRP, CCK and galanin were increased while beta -CGRP mRNA level was decreased after axotomy. The levels of mRNAs for these peptides returned to the control values by 2-4 weeks after injury, nerve transection had greater effects on beta -CGRP, CCK and galanin mRNAs than did nerve crush. These changing patterns of neuropeptides in motoneurons do not coincide with that of NGF-receptor mRNA after the same procedures ; the increase of NGF-receptor mRNA with crushing was more pronounced than with transection from the 3rd to the 14th day after the injury. These findings suggest that the production of these peptides in motoneurons is not regulated by NGF. Less

乙酰胆碱（ACH）长期以来一直是运动神经元中神经递质的唯一候选者。分子生物学和应用形态学技术的最新进展揭示了在摩托神经元中存在神经肽。这些胡椒被认为可以调节摩托神经元和肌肉的活性，或对它们发挥神经营养作用。除胡椒粉外，在摩托神经元中还合成了神经递质受体，表明各种神经递质调节运动神经元的活性。此外，运动神经元受神经营养因子的控制，例如神经生长因子（NGF）。已经证明，NGF受体mRNA和NGF受体蛋白在发育中的运动神经元中均表达，并且在某些实验条件下也表达了成熟的运动神经元。在演讲研究中，我们在现场杂交组织化学上进行了工作，以证明这些肽和受体的产生是如何在受伤的运动神经元中调节的。在这些神经元中，轴突切开术会导致α -CGRP mRNA的增加，但没有β -CGRP mRNA，表明α -CGRP和β -CGRP受到独立调节，并且在运动神经元中具有不同的作用。我们还表明，在运动神经元中，构建神经元烟碱ACH受体的α-和β-亚基也有所不同。 Alpha 3和Beta 2亚基mRNA在大鼠面部运动神经元的12％和40％中表达。 Alpha 3亚基mRNA信号在响应轴切开术而消失，而Beta 2亚基mRNA信号显着增强。分别38％，55％和7％的大鼠面部运动神经元分别表达α -CGRP，beta -CGRP和CCK mRNA。未观察到含有运动神经元的甘丙蛋白mRNA。轴突切开术后Beta -CGRP mRNA水平升高，而α -CGRP，CCK和Galanin的mRNA水平升高。这些肽的mRNA水平在受伤后2-4周恢复到对照值，而神经转导对β -CGRP，CCK和Galanin mRNA具有更大的影响。运动神经元中神经肽的这些变化模式与相同的过程后的NGF受体mRNA不一致。与从受伤后的第三天到第14天的翻译相比，用压碎的NGF受体mRNA的增加更为明显。这些发现表明，在运动神经元中这些肽的产生不受NGF的调节。较少的