Abstract
A large body of evidence indicates that astrocytes play an important role in a range of brain functions through calcium (Ca2+) signaling. Experimentally evoking Ca2+ signaling is a useful technique for investigating the functions of astrocytes. However, conventional stimulation methods typically have poor spatio-temporal precision, and some are invasive. Our group has developed a technique to overcome these problems, in which astrocytes are photostimulated with a femtosecond laser. In the current study, we applied this method to a hippocampal neural network to explore astrocytic functions in detail. The results revealed that applying photostimulation to astrocytes in a cultured hippocampal astrocyte-neuron network caused the following changes: (i) Synchronous Ca2+ oscillations in neurons were induced; (ii) spontaneous Ca2+ synchrony instantaneously emerged; and (iii) high-frequency spontaneous Ca2+ synchrony was regulated. Thus, astrocytic Ca2+ signaling evoked by photostimulation was found to modulate synchronous Ca2+ oscillations in hippocampal neurons. We propose that photostimulation with a femtosecond laser will serve as a powerful tool in investigating astrocytic functions at the network level.
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Zhao, Y., Liu, X., Zhang, Y. et al. Modulation of synchronous calcium oscillations in hippocampal neurons by photostimulation of astrocytes with femtosecond laser. Chin. Sci. Bull. 55, 3436–3440 (2010). https://doi.org/10.1007/s11434-010-3376-z
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DOI: https://doi.org/10.1007/s11434-010-3376-z