The calpain blocker, CI3, prevents the effect of SD on AnkG staining and dynamic gain. A, Confocal images obtained from coronal cortical slices subjected to brief hypoxic episodes in the presence of CI3 (40 μm). B, Number of AnkG-positive AISs counted in 1 mm2 section in control, recovered, and SD + CI3 slices in n = 8, n = 6, and n = 7 slices, respectively. C, Ratio of the number of AnkG-stained AISs to the number of NeuN-stained neuronal somata in control, recovered, and SD + CI3 slices. D, In the presence of CI3, SD has little effect on dynamic gain (CI3, purple, n = 12 neurons; control, black, n = 6 neurons). Faded error bars indicate 5%–95% CIs of bootstrapped data (1000 repetitions). Box charts represent median (horizontal line), 25th-75th percentile (box), and standard deviation (bars). *p < 0.05, **p < 0.01, ***p < 0.001. ns indicates p > 0.05.