@article{oai:teapot.lib.ocha.ac.jp:00043222,
 author = {MONAI, Hiromu},
 issue = {特別号},
 journal = {お茶の水女子大学自然科学報告},
 month = {Sep},
 note = {紀要論文, Astrocytes are neural cells that play an essential role in the modulation of neurotransmission and synaptic plasticity in the brain, yet the main target of neurophysiological research has been neural networks. One reason is that astrocytes show less fluctuation in their membrane potentials, unlike neurons, and it is difficult to evaluate their activity by electrical measurements. On the other hand, the Ca2+ imaging technique has revealed that astrocytes can vary widely in intracellular Ca2+ concentration. In our laboratory, we use a transgenic mouse line (G7NG817) that expresses G-CaMP7, a Ca2+ sensor protein, in astrocytes and a portion of the excitatory neurons, to visualize cortical function in vivo. As G7NG817 mice show a dense expression of G-CaMP7 in the cerebral cortex, it is possible to image brain Ca2+ dynamics without thinning the skull using standard epifluorescence microscopy. The advantage of this transcranial cortex-wide imaging technique is to observe the more native and stable activity of a wide field of view even under awake conditions compared to the conventional open-skull imaging method because it induces less stress and inflammation in the brain. Using the G7NG817 mouse, we have reported that specific neuronal populations in the cortex were activated by distinct modalities, such as light, sound, or whisker mechanical stimulation. It is confirmed that regional and rapid responses were due to neuronal activities. On the contrary, astrocytes showed more global and slower dynamics than neurons. We found that it is possible to discriminate neuronal and astrocytic activities, even under transcranial imaging, by the different dynamics of the Ca2+ event. In this review, we will review the recent development of the fully intact transcranial cortex-wide Ca2+ imaging technique, and in the latter part, introduce some practical examples of G7NG817 mice.},
 pages = {39--50},
 title = {Transcranial Cortex-Wide Fluorescence Imaging through a Fully Intact Skull, as a Powerful Tool for Functional Mapping: Less Invasive Macroscopic Imaging of Cortical Ca2+ Dynamics},
 volume = {71},
 year = {2020}
}