中文摘要：

证据的大身体显示星形细胞通过发信号的钙(Ca2+) 在大脑函数的一个范围起一个重要作用。试验性地唤起 Ca2+ 发信号是为调查星形细胞的功能的一种有用技术。然而，常规刺激方法典型地有差的时间空间的精确，和一些是侵略的。我们的组开发了一种技术克服这些问题，星形细胞在是有 femtosecond 激光的 photostimulated。在当前的学习，我们把这个方法用于一个海马趾的神经网络详细探索 astrocytic 功能。结果表明到在一个有教养的海马趾的星形细胞神经原网络的星形细胞的那适用的 photostimulation 引起了下列变化：(i) 在神经原的同步 Ca2+ 摆动被导致；(ii ) 自发的 Ca2+ synchrony 即刻地出现了；并且(iii ) 高周波的自发的 Ca2+ synchrony 被调整。因此，发信号由 photostimulation 唤起了的 astrocytic Ca2+ 被发现在海马趾的神经原调制同步 Ca2+ 摆动。我们建议有 femtosecond 激光的 photostimulation 将在在网络水平调查 astrocytic 函数用作一个强大的工具。

英文摘要：

A large body of evidence indicates that astrocytes play an important role in a range of brain functions through calcium （Ca2＋） signaling. Experimentally evoking Ca2＋ signaling is a useful technique for investigating the functions of astrocytes. However, conventional stimulation methods typically have poor spatio-temporal precision, and some are invasive. Our group has developed a technique to overcome these problems, in which astrocytes are photostimulated with a femtosecond laser. In the current study, we applied this method to a hippocampal neural network to explore astrocytic functions in detail. The results revealed that apply- ing photostimulation to astrocytes in a cultured hippocampal astrocyte-neuron network caused the following changes： （i） Syn- chronous Ca2＋ oscillations in neurons were induced; （ii） spontaneous Ca2＋ synchrony instantaneously emerged; and （iii） high-frequency spontaneous Ca2＋ synchrony was regulated. Thus, astrocytic Ca2＋ signaling evoked by photostimulation was found to modulate synchronous Ca2＋ oscillations in hippocampal neurons. We propose that photostimulation with a femtosecond laser will serve as a powerful tool in investigating astrocytic functions at the network level.