Simultaneous Infrared-Induced Calcium Signaling in Astrocytes and Neurons in Mice Spinal Cord Slices

Infrared neural stimulation (INS) is an optical method, label-free, not cell-type specific, that can modulate neural activity with a high spatial resolution. Recent studies have shown that it can also trigger calcium signaling in non-excitable cells such as astrocytes. Astrocytes participate in neural communication, and play a key role in many neurodegenerative diseases in a calcium-dependent way. As infrared triggers calcium signaling in both astrocytes and neurons, it appears as a good technique to explore the influence of astrocytes in neuronal communication and pathology. However, questions remain on how the same infrared paradigm affect both astrocytes and neurons, and how their respective infrared-induced activities are affecting each other. In this work, we show infrared-induced calcium signals in both astrocytes and neurons simultaneously in mice spinal cord slices using two different genetically encoded calcium indicators. Preliminary results tend to demonstrate that infrared exposure induces intercellular calcium waves in the astrocytic network. The influence of astrocytic signaling on neuronal activity is also investigated.