权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Autonomous Distributed Control Systems in the Enteric Nervous System

肠神经系统的自主分布式控制系统

基本信息

批准号：
04044056
负责人：
KATAYAMA Yoshifumi
金额：
$ 7.36万
依托单位：
Tokyo Medical and Dental University
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1993
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-04044056/
关键词：
Distributed control system Enteric nervous system Myenteric plexus Submucous plexus Neuroactive substances Synaptic transmission Growth cone Neural net アウェルバッハ神経叢マイスナー神経叢神経伝達成長錐 GTP結合蛋白カルシウム

项目摘要

Reports from all investigators are summarized as follows.It was demonstrated that the ability of provoking peristalsis, though impaired, could be preserved in the isolated guinea-pig ileum from which both mucosa and submucosa were mechanically removed. ATP and L-DOPA modulated transmitter release in the enteric nervous system of the guinea-pig ileum and caecum.In the in vitro models of intestinal ischaemia using guinea-pigs, only a few myenteric neurons showed the 'classical' neuronal membrane response indicative of ischaemic damage, whereas other myenteric and submucous neurons showed no change in their electrical properties or synaptic transmission.Neuropeptide Y (NPY, 1-100 nM) was found to inhibit the slow IPSPs in the caecum submucous plexus of guinea-pigs ; NPY did not affect the electrophysiological properties nor the response of the cells to noradrenaline, the mediator for the slow IPSPs. Moreover, up to 300 nM, NPY had no detectable effect on the fast and slow EPSPs. Thus, NPY might act only presynaptically and selectively to depress noradrenaline release. The slow IPSPs were rare events in neurons of the descending colon, compared with the caecum. This is preliminary evidence for another important example of regional differences in the function of the enteric neurons.Cholinergic neurons of the diagonal band of Broca were isolated from fetus or new-born rats and were kept in culture. Histo- and immunocytochemical invesstigations on these neurons disclosed the presence of cholinergic metabolism in growth cones at high level even before synapse-formation. Rapid elongation of filopoida from growth cones was observed in response to high potassium stimulation. Con-A-coated gold particles possibly attached to growth cone membrane moved apparently in a Brownian manner within some restricted area, and their movement could be controlled by means of laser tweezers.

所有研究者的报告总结如下。结果表明，在机械去除粘膜和粘膜下层的离体豚鼠回肠中，尽管引起蠕动的能力受损，但仍可保留。 ATP 和 L-DOPA 调节豚鼠回肠和盲肠肠神经系统中递质的释放。在豚鼠肠缺血的体外模型中，只有少数肌间神经元表现出指示缺血损伤的“经典”神经元膜反应，而其他肌间和粘膜下神经元的电特性或突触没有变化。神经肽 Y（NPY，1-100 nM）被发现可抑制豚鼠盲肠粘膜下丛中的缓慢 IPSP； NPY 不影响电生理特性，也不影响细胞对去甲肾上腺素（慢 IPSP 的介质）的反应。此外，高达 300 nM 的 NPY 对快速和慢速 EPSP 没有可检测到的影响。因此，NPY 可能仅在突触前选择性地抑制去甲肾上腺素的释放。与盲肠相比，降结肠神经元中缓慢的 IPSP 是罕见的事件。这是肠神经元功能区域差异的另一个重要例子的初步证据。布罗卡对角线带的胆碱能神经元从胎儿或新生大鼠中分离出来并保持在培养物中。对这些神经元的组织和免疫细胞化学研究表明，甚至在突触形成之前，生长锥中就存在高水平的胆碱能代谢。观察到丝状体从生长锥中快速伸长以响应高钾刺激。可能附着在生长锥膜上的Con-A包被的金颗粒在一定的限制区域内明显以布朗方式移动，并且它们的移动可以通过激光镊子来控制。