Göbel Werner, Helmchen Fritjof
Department of Neurophysiology, Brain Research Institute, Winterthurerstr 190, CH-8057, Zurich, Switzerland.
J Neurophysiol. 2007 Dec;98(6):3770-9. doi: 10.1152/jn.00850.2007. Epub 2007 Sep 26.
Imaging technologies are well suited to study neuronal dendrites, which are key elements for synaptic integration in the CNS. Dendrites are, however, frequently oriented perpendicular to tissue surfaces, impeding in vivo imaging approaches. Here we introduce novel laser-scanning modes for two-photon microscopy that enable in vivo imaging of spatiotemporal activity patterns in dendrites. First, we developed a method to image planes arbitrarily oriented in 3D, which proved particularly beneficial for calcium imaging of parallel fibers and Purkinje cell dendrites in rat cerebellar cortex. Second, we applied free linescans -- either through multiple dendrites or along a single vertically oriented dendrite -- to reveal fast dendritic calcium dynamics in neocortical pyramidal neurons. Finally, we invented a ribbon-type 3D scanning method for imaging user-defined convoluted planes enabling simultaneous measurements of calcium signals along multiple apical dendrites. These novel scanning modes will facilitate optical probing of dendritic function in vivo.
成像技术非常适合用于研究神经元树突，而树突是中枢神经系统中突触整合的关键要素。然而，树突通常垂直于组织表面排列，这阻碍了体内成像方法的应用。在此，我们介绍了用于双光子显微镜的新型激光扫描模式，该模式能够对树突中的时空活动模式进行体内成像。首先，我们开发了一种对三维空间中任意取向的平面进行成像的方法，这被证明对大鼠小脑皮质中平行纤维和浦肯野细胞树突的钙成像特别有益。其次，我们应用自由线扫描——要么穿过多个树突，要么沿着单个垂直取向的树突——来揭示新皮质锥体神经元中快速的树突钙动力学。最后，我们发明了一种带状三维扫描方法，用于对用户定义的卷曲平面进行成像，从而能够同时测量多个顶端树突上的钙信号。这些新型扫描模式将有助于在体内对树突功能进行光学探测。
