Chemical Biology Program.
Biophysics Program.
J Neurosci. 2019 Jun 19;39(25):4889-4908. doi: 10.1523/JNEUROSCI.0168-19.2019. Epub 2019 Apr 5.
Optical tools for simultaneous perturbation and measurement of neural activity open the possibility of mapping neural function over wide areas of brain tissue. However, spectral overlap of actuators and reporters presents a challenge for their simultaneous use, and optical scattering and out-of-focus fluorescence in tissue degrade resolution. To minimize optical crosstalk, we combined an optimized variant (eTsChR) of the most blue-shifted channelrhodopsin reported to-date with a nuclear-localized red-shifted Ca indicator, H2B-jRGECO1a. To perform wide-area optically sectioned imaging in tissue, we designed a structured illumination technique that uses Hadamard matrices to encode spatial information. By combining these molecular and optical approaches we made wide-area functional maps in acute brain slices from mice of both sexes. The maps spanned cortex and striatum and probed the effects of antiepileptic drugs on neural excitability and the effects of AMPA and NMDA receptor blockers on functional connectivity. Together, these tools provide a powerful capability for wide-area mapping of neuronal excitability and functional connectivity in acute brain slices. A new technique for simultaneous optogenetic stimulation and calcium imaging across wide areas of brain slice enables high-throughput mapping of neuronal excitability and synaptic transmission.
用于同时扰动和测量神经活动的光学工具为绘制大脑组织大片区域的神经功能提供了可能。然而，驱动器和报告器的光谱重叠给它们的同时使用带来了挑战，组织中的光散射和离焦荧光降低了分辨率。为了最小化光学串扰，我们将迄今为止报道的最蓝移通道蛋白变体（eTsChR）与核定位的红移 Ca 指示剂 H2B-jRGECO1a 结合使用。为了在组织中进行大面积光学切片成像，我们设计了一种使用 Hadamard 矩阵对空间信息进行编码的结构照明技术。通过结合这些分子和光学方法，我们在来自雌雄小鼠的急性脑片中制作了大面积功能图谱。这些图谱覆盖了皮层和纹状体，并探测了抗癫痫药物对神经兴奋性的影响，以及 AMPA 和 NMDA 受体阻滞剂对功能连接的影响。这些工具结合在一起，为在急性脑片中进行大面积神经元兴奋性和功能连接的映射提供了强大的能力。一种用于在大脑切片大片区域中同时进行光遗传学刺激和钙成像的新技术，实现了神经元兴奋性和突触传递的高通量映射。
