Making sense of astrocytic calcium signals - from acquisition to interpretation

Although not electrically excitable, astrocytes display a complex repertoire of intracellular Ca(2+)signalling. Semyanov, Henneberger and Agarwal describe experimental preparations and methods for studying Ca(2+)activity in astrocytes, their limitations and the ongoing technical and conceptual challenges in the interpretation of astrocytic Ca(2+)events and their spatio-temporal patterns. Astrocytes functionally interact with neurons and with other brain cells. Although not electrically excitable, astrocytes display a complex repertoire of intracellular Ca(2+)signalling that evolves in space and time within single astrocytes and across astrocytic networks. Decoding the physiological meaning of these dynamic changes in astrocytic Ca(2+)activity has remained a major challenge. This Review describes experimental preparations and methods for recording and studying Ca(2+)activity in astrocytes, focusing on the analysis of Ca(2+)signalling events in single astrocytes and in astrocytic networks. The limitations of existing experimental approaches and ongoing technical and conceptual challenges in the interpretation of astrocytic Ca(2+)events and their spatio-temporal patterns are also discussed.