As transient intracellular Ca2+ changes play an important role in many essential processes including neuronal and astrocytic plasticity, tracking brain activity via Ca2+ is crucial. Unlike hemodynamics, Ca2+ change must be measured optically using an ionic fluorescent Ca2+ indicator. Here, we combine our highly sensitive multimodality optical imaging platform with genetically encoded Ca2+ indicator (GCaMP6f) expressed in neurons or astrocytes in somatosensory cortex, which enables simultaneous tracking of single-stimulation-evoked neuronal, astrocytic Ca2+ transients along with the corresponding hemodynamic responses at high spatiotemporal resolutions. We imaged neuronal and astrocytic Ca2+ transients from mouse cortex in response to a single electrical pulse (3mA, 0.3ms). Our results show that the neuronal Ca2+ responses were strong (ΔF/FN=6.4±0.29%), fast (latency τN=6±2.7ms) and of short duration (ΔtN=537±34ms) whereas the astrocyte responses were weak, slow and long-lasting (i.e., ΔF/FA=1.7±0.1%, τA=313±65ms, ΔtA =993±48ms). The synchronized activities among astrocytes were temporally less correlated than those among neurons. These results demonstrate the capability of optical detection of cell-specific Ca2+ activities from synchronized neuronal, astrocyte ensembles concurrently with the hemodynamic responses within the neuro-glio-vascular network, which can facilitate the study of the roles of astrocytes in the neurovascular coupling process. We also report time-lapse image results to analyze the interactions between stimuli-evoked neurovascular response versus the spontaneous cortical slow oscillations for brain functional studies
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