MECHANICAL, THERMAL, AND OPTICAL SIGNS OF EXCITATION IN THE NERVOUS SYSTEM

神经系统兴奋的机械、热和光学迹象

• 批准号: 2578728
• 负责人: I TASAKI
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF MENTAL HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2578728
• 关键词: Osteichthyes; calcium flux; electrophysiology; electrostimulus; fish electric organ; heat stimulus; neural transmission; neurophysiology; neurotransmitter transport; physical chemical interaction; synapses; thermogenesis; thermometry

We have continued, during this fiscal year, our investigation into the nature of the rapid structural changes in the nervous tissues associated with the process of excitation. Last year, we found, employing the electric organ of the ray known for its massive cholinergic innervation, that the chemical transmitter released from the nerve endings evokes rapid swelling (a rise in the water content) in the postsynaptic elements. We have demonstrated, during the early period of this fiscal year, that these mechanical changes are accompanied by large, readily detectable optical changes in the tissues, i.e., by a pronounced fall followed by a sustained rise in light scattering. We believe that the release of Ca-ions from the postsynaptic membrane triggered by the chemical transmitter release (Neuman et al., 1973-1976) is at the base of these mechanical and optical changes. Later on, we devoted our effort to the development of a new type of heat detector by using extremely thin polyurea film (Takahashi et al., J. Appl. Phys. 70;6983, 1991). By virtue of the large dipole moment carried by the urea groups in the polymer, it was found possible to endow such film with strong pyroelectricity. Responding to our request, Tsukuba Institute for Super Materials in Japan sent us samples of pyroelectric polyurea film (deposited on five-micron thick mylar layer). The records of thermal changes in the ray electric organ, obtained with the detectors we have fabricated recently, appear to indicate that the onset of heat production by the tissue is roughly simultaneous (within 0.5 msec) with the osnet of the postsynaptic potential.

在本财政年度内，我们继续调查 相关神经组织的快速结构变化的本质 伴随着刺激的过程。去年，我们发现，雇佣了 射线的电子器官，以其大量的胆碱能神经支配而闻名， 从神经末梢释放的化学递质唤起 突触后的快速肿胀(水含量的增加) 元素。在本财年的早期阶段，我们已经证明 这些机械变化随之而来的是巨大的、容易的 组织中可检测到的光学变化，即通过明显的坠落 随之而来的是光散射持续上升。我们相信， 突触后膜钙离子的释放 化学发射器的释放(Neuman等人，1973-1976)在基地 这些机械和光学上的变化。后来，我们把我们的努力 利用极薄材料研制新型热敏探测器 聚脲薄膜(Takahashi等人，J.Appl.太棒了。70；6983,1991年)。通过 尿素基团携带的大偶极矩的优点 聚合物，人们发现有可能赋予这种薄膜以坚固的 热释电。应我们的要求，筑波超级学院 日本的材料寄给我们热释电聚脲薄膜样品 (沉积在5微米厚的聚酯薄膜上)。关于热能的记录 射线电器官的变化，用我们现有的探测器获得 最近制造的，似乎表明热产生的开始 与组织大致同步(在0.5毫秒内) 突触后电位。