Analysis of neurosecretory activities by real-time image processing

通过实时图像处理分析神经分泌活动

基本信息

批准号：
62570047
负责人：
TERAKAWA Susumu
金额：
$ 1.22万
依托单位：
Okazaki National Research Institutes, National Institute for Physiological Sciences
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1988
项目状态：
已结题

项目摘要

In order to determine the origin of the light scattering change associated with the secretory activity in nervous tissues, transparency of these tissues was examined through a video camera attached to a high power microscope. The video signal was processed to produce contrast enhanced differential images. By virtue of this system accurate site of optical response could be visualized.In the sinus gland of the lobster, the site of the optical response was nerve terminals, and not smooth muscles, blood vessels or other contractile elements. The image could be reversibly suppressed by Cd-containing or Ca-deficient medium. The response could be greatly enhanced by tetraethylammonium and ouabain.Differential images of the rat neurohypophysis was obtained with a highest spatial resolution. They consisted of many small dots of 0.3 um in diameter inside nerve terminals, suggesting that individual secretory granules inside the nerve terminals are the site of optical response. The amplitude of scattering response increased with the frequency of stimulation. Therefore, the scattering response share the same property as that of peptide release from this tissue. Furthermore, the amplitude had a linear relationship with amount of vasopressin measured by radioimmunoassay in the same preparation simultaneously. From these findings, scattering response can be most directly ascribed to the exocytosis of individual secretory granules.This mechanism was further confirmed in an isolated single chromaffin cell which showed a clear image of exocytosis directly under video enhanced bright-field microscope. The exocytosis appeared as an increase in light intensity on very localized spot on the plasma membrane. The time course of the light intensity in active part of a single cell showed a change very similar to scattering change observed by a photodiode.The present study established that the scattering response of the secretory cell is a direct measure of exocytotic activities.

为了确定与神经组织中分泌活性相关的光散射变化的起源，通过连接到高功率显微镜的摄像机检查了这些组织的透明度。处理视频信号以产生对比度增强的差异图像。根据该系统的精确位点，可以看到光学响应的精确位点。在龙虾的窦腺体中，光学响应的位点是神经末端，而不是光滑的肌肉，血管，血管或其他收缩元件。可以通过含有CD的或CA缺陷培养基可逆地抑制图像。四乙基铵和ouabain可以大大增强反应。大鼠神经摩physys的差异图像是通过最高的空间分辨率获得的。它们由许多小点组成，直径为0.3 um的神经末端，这表明神经末端内的个体分泌颗粒是光学反应的位置。散射反应的幅度随刺激的频率而增加。因此，散射响应具有与从该组织中释放的肽释放相同的特性。此外，振幅与通过放射免疫测定法在同一制剂中测量的加压素量具有线性关系。从这些发现中，散射反应最直接地归因于单个分泌颗粒的胞吐作用。在一个孤立的单个铬蛋白细胞中进一步证实了这种机制，该机制在视频增强的明显的明显的胞吐作用图像中，在视频增强了明显的明亮场上显微镜下。胞吐作用似乎是在质膜上非常局部斑点上的光强度的增加。单个细胞活跃部分的光强度的时间过程显示出与光电二极管观察到的散射变化非常相似的变化。目前的研究表明，分泌细胞的散射响应是胞吐活性的直接衡量。