Figure 2.

Characterization of Ca²⁺ signaling events in astrocyte processes in organotypic cultures of rat hippocampus. Astrocytes in organotypic cultures of rat hippocampus were transfected with a membrane-targeted-mCherry fluorescent protein driven by a GFAP promoter (A; GFA_ABC1D-mCherry) and the membrane-targeted genetic Ca²⁺ indicator LCK-GCaMP5G (B, C). Spontaneous Ca²⁺ increases were recorded over a 10 min imaging window. Individual processes (B, C) from the astrocyte depicted in A (red and green overlays) were traced and kymographs created from the time-series. [Ca²⁺]_i increases are depicted using a pseudo-color lookup table. Individual Ca²⁺ transients were analyzed for amplitude (D; peak ΔF/F0), distance propagated (E; μm), and tau (F, seconds) and the results depicted as histographs (n = 742 spikes, 111 processes, 15 cells). G, Representative trace depicts LCK-GCaMP5G fluorescence changes from multiple processes of the same astrocyte treated with the TRPA1 antagonist (A967079, n = 3 cells, 16 processes).