Fig. 1
Cardiac arrest causes a burst of calcium wave in brain. a Schematic showing the experimental scheme. b Schematic showing cardiac arrest (CA) model in zebrafish. A glass micropipette was used to press zebrafish heart (red) until the heart stop beating, neuronal activity was examined with in vivo time-lapse confocal imaging after CA. c Calcium activity of Tg (HuC:GCaMP5) transgenic zebrafish in different brain regions after CA (lateral view). ROI1 (red ellipses), ROI2 (green ellipses) and ROI3 (yellow ellipses) marked neuron in hindbrain, midbrain and telencephalon, respectively. Scale bar: 100 μm. d Calcium activity of three regions of interest in (c) at a higher time resolution. The arrows mark the onset of calcium activities in each region. e Time-lapse confocal images showing the lateral view of the brain in live Tg (HuC:GCaMP5) transgenic zebrafish in control and CA zebrafish at 7 day post-fertilization (dpf). 0 s indicating calcium wave onset. Scale bar: 100 μm. f The change in fluorescence intensity of neuron in midbrain in individual zebrafish during CA. g Occurrence probability of calcium waves in control and CA zebrafish (*** P<0.001, chi-square test). h Quantification of the latency of CA to calcium wave generation in CA zebrafish. Numbers in the histograms represent the number of embryos analyzed in each group