Physiological study of synchronous firing activity in insect neurosecretory cell systems

昆虫神经分泌细胞系统同步放电活动的生理研究

基本信息

批准号：
11640681
负责人：
ICHIKAWA Toshio
金额：
$ 2.24万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

There are four pairs of neurosecretory cells producing bombyxin, an insulin-related peptide, in the brain of Bombyx mori. Electrical signals of the bombyxin-producing cells were identified and short-and long-term activity patterns of the cells throughout the pupal period were analyzed. Activity pattern of the cells was characterized by periodic discharges of a volley of action potentials. Periodicity of the electrical activity depended on the temperature and mean±SD of periods was 34.7±4.8 min at 26℃. Four cells in a brain hemisphere were functionally heterogeneous : individual cells had specific activity amplitudes and rhythms, thereby suggesting that an ultradian activity rhythm of a cell originates from its intrinsic pacemaker activity. There was no significant diel (circadian) oscillation in the electrical activity. Daily activity patterns had a maximum at an early stage (day-2 or 3) of pupal period. Firing correlations were examined among four pairs of bombyxin-producing cells with an ultradian bursting rhythm. Cross-correlation analyses of spiking activities between pairs of simultaneously active cells usually revealed a significant correlation of firings : 20-50% of spikes of a cell fired within 0.2 s before or after the other cell's spikes fired. The mutual, excitatory communication among neurosecretory cells make the set of cells a weakly coupled multi-oscillator system that may generates a pulsatile release pattern of their hormone that seems to be an efficient temporal pattern for maintaining hormonal actions.

在Bombyx Mori的大脑中，有四对产生Bombyxin（一种与胰岛素相关的肽）的神经分泌细胞。鉴定出产生Bombyxin的细胞的电信号，并在整个pupal期间分析细胞的短期和长期活性模式。细胞的活性模式的特征是定期排放一系列动作电位。电动活性的周期性取决于温度和平均周期的平均值±SD，为34.7±4.8分钟，分别为26℃。脑半球中的四个细胞在功能上是异质的：单个细胞具有特定的活性幅度和节奏，从而表明细胞的超级活性节奏来自其内在的起搏器活性。电活动中没有明显的DIEL（昼夜节律）振荡。每日活动模式在幼崽时期的早期阶段（第2天或第3天）中最大。发射相关性我们在四对产生Bombyxin的细胞中检查了超大爆发节奏。对成对的简单活性细胞之间的尖峰活动的互相关分析通常显示出发射的显着相关性：在另一个细胞的尖峰发射之前或之后，在0.2 s内发射的细胞的尖峰中有20％至50％。神经分泌细胞之间的相互激动人心的通信使一组细胞成为一个弱耦合的多振荡器系统，该系统可能会产生其马内的脉动释放模式，这似乎是维持马雌动作的有效临时模式。