INSERM U1128, Laboratory of Neurophysiology and New Microscopy, Université Paris Descartes, Paris, 75006, France.
NeuroSpin, Bât 145, Commissariat à l'Energie Atomique-Saclay Center, Gif-sur-Yvette, 91191, France.
Nat Commun. 2019 Mar 7;10(1):1110. doi: 10.1038/s41467-019-09082-4.
Imaging based on blood flow dynamics is widely used to study sensory processing. Here we investigated the extent to which local neuronal and capillary responses (two-photon microscopy) are correlated to mesoscopic responses detected with fast ultrasound (fUS) and BOLD-fMRI. Using a specialized chronic olfactory bulb preparation, we report that sequential imaging of the same mouse allows quantitative comparison of odour responses, imaged at both microscopic and mesoscopic scales. Under these conditions, functional hyperaemia occurred at the threshold of neuronal activation and fUS-CBV signals could be detected at the level of single voxels with activation maps varying according to blood velocity. Both neuronal and vascular responses increase non-linearly as a function of odour concentration, whereas both microscopic and mesoscopic vascular responses are linearly correlated to local neuronal calcium. These data establish strengths and limits of mesoscopic imaging techniques to report neural activity.
血流动力学成像被广泛用于研究感觉处理。在这里，我们研究了局部神经元和毛细血管反应（双光子显微镜）与使用快速超声（fUS）和 BOLD-fMRI 检测到的中尺度反应之间的相关性。使用专门的慢性嗅球制备物，我们报告说，对同一只老鼠进行连续成像允许在微观和中尺度上定量比较气味反应。在这些条件下，功能充血发生在神经元激活的阈值处，并且可以在激活图根据血流速度而变化的单个体素水平检测到 fUS-CBV 信号。神经元和血管反应都随着气味浓度的增加呈非线性增加，而微观和中尺度血管反应都与局部神经元钙线性相关。这些数据确定了中尺度成像技术报告神经活动的优势和局限性。
