A new approach to inhibiting astrocytic IP3-induced intracellular calcium increase in an astrocyte–neuron co-culture system

doi:10.1016/j.brainres.2005.06.056

Brain Research

Volume 1055, Issues 1–2, 7 September 2005, Pages 196-201

https://doi.org/10.1016/j.brainres.2005.06.056 Get rights and content

Abstract

Astrocytes exhibit dynamic Ca²⁺ mobilization, such as Ca²⁺ wave and Ca²⁺ oscillation, via an inositol 1,4,5-triphosphate-induced Ca²⁺ release (IICR)-dependent mechanism. The physiological functions of astrocytic Ca²⁺ mobilization, however, are poorly understood. To investigate this issue, we created a plasmid encoding an enhanced green fluorescent protein-tagged inositol 1,4,5-triphosphate absorbent protein and expressed it in cultured astrocytes. Expression of this protein inhibited both IICR and the Ca²⁺ wave in cultured astrocytes. By combining this method to the single cell electroporation technique, we were able to inhibit IICR specifically in astrocytes in an astrocyte–neuron co-culture system. Our approach provides a useful tool for direct examination of the physiological role of astrocytic Ca²⁺ signaling on neuronal function.

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Acknowledgments

This work was supported by a WAKATE Grant-in-Aid for Scientific Research (to Sheng-Tian Li) from the Ministry of Education, Culture, Sports, Science and Technology of Japan. We thank T. Ogawa and X-J. Han for their technical assistance in culture preparation.

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Citation Excerpt :
Therefore, it is critical to understand how the Ca2+ oscillations are generated and modulated. Many experimental results suggested that an inositol 1,4,5-triphosphate (IP3) dependent calcium-induced calcium release (CICR) mechanism is involved in Ca2+ oscillations (16,18,19). This was central to the process in the intracellular space (ICS).
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Short CommunicationA new approach to inhibiting astrocytic IP3-induced intracellular calcium increase in an astrocyte–neuron co-culture system

Abstract

Section snippets

Acknowledgments

Neuron

Trends Pharmacol. Sci.

Differentiation

Life Sci.

Prog. Neurobiol.

J. Biol. Chem.

Regulation of gene expression in hippocampal neurons by distinct calcium signaling pathways

Science

Neurobiology. Cholesterol-making or breaking the synapse

Science

Control of synaptic strength by glial TNFalpha

Science

Prostaglandins stimulate calcium-dependent glutamate release in astrocytes

Nature

Differential frequency dependence of P2Y1- and P2Y2- mediated Ca2+ signaling in astrocytes

J. Neurosci.

Intercellular calcium signaling and gap junctional communication in astrocytes

Glia

ATP released from astrocytes mediates glial calcium waves

J. Neurosci.

GLIA: listening and talking to the synapse

Nat. Rev. Neurosci.

Short Communication
A new approach to inhibiting astrocytic IP₃-induced intracellular calcium increase in an astrocyte–neuron co-culture system

Differential frequency dependence of P2Y1- and P2Y2- mediated Ca²⁺ signaling in astrocytes