Imaging local brain activity of multiple freely moving mice sharing the same environment

• Published in: Scientific reports Vol. 9; no. 1; p. 7460
• Main Authors: Inagaki, Shigenori, Agetsuma, Masakazu, Ohara, Shinya, Iijima, Toshio, Yokota, Hideo, Wazawa, Tetsuichi, Arai, Yoshiyuki, Nagai, Takeharu
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 16.05.2019; Nature Publishing Group
• Subjects: 59/5; 631/1647/245/2222; 631/378/2613; 64/60; Animals; Cells, Cultured; Environment; Fluorescence Resonance Energy Transfer - methods; Humanities and Social Sciences; Information processing; Luminescent Proteins - genetics; Luminescent Proteins - metabolism; Male; Membrane Potentials; Mental disorders; Mice; Mice, Inbred C57BL; Movement; multidisciplinary; Nervous system; Neuroimaging; Neurosciences; Optogenetics - methods; Patch-Clamp Techniques - methods; Phosphoric Monoester Hydrolases - genetics; Phosphoric Monoester Hydrolases - metabolism; Science; Science (multidisciplinary); Visual cortex; Visual Cortex - diagnostic imaging; Visual Cortex - metabolism; Visual Cortex - physiology
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-019-43897-x

Electrophysiological field potential dynamics have been widely used to investigate brain functions and related psychiatric disorders. Considering recent demand for its applicability to freely moving subjects, especially for animals in a group and socially interacting with each other, here we propose a new method based on a bioluminescent voltage indicator LOTUS-V. Using our fiber-free recording method based on the LOTUS-V, we succeeded in capturing dynamic change of brain activity in freely moving mice. Because LOTUS-V is the ratiometric indicator, motion and head-angle artifacts were not significantly detected. Taking advantage of our method as a fiber-free system, we further succeeded in simultaneously recording from multiple independently-locomotive mice that were freely interacting with one another. Importantly, this enabled us to find that the primary visual cortex, a center of visual processing, was activated during the interaction of mice. This methodology may further facilitate a wide range of studies in neurobiology and psychiatry.