Fig. 2
Changes in glucose metabolites in brains of control, SD and RSD zebrafish. A Graphs represent quantification of selected glucose metabolites by GC–MS/MS in the brains of control and SD zebrafish with or without the fear context. A fear context memory test was conducted after the SD. After a 6-h interval following the memory test, the brains were sacrificed for metabolic analysis. The Mann–Whitney U test was used for statistical comparisons of groups (*p < 0.05 and **p < 0.01). Cont, control; Con-F, 6 h after fear context in control group; SD, sleep-deprivation; SD-F, 6 h after fear context in SD group. B Graphs represent quantification of selected glucose metabolites using GC–MS/MS in the brains of control and RSD zebrafish. Statistical analysis was carried out by Mann–Whitney U test (*p < 0.05 and **p < 0.01 versus Con). C mRNA expression levels of pooled brain samples (n = 3/group) were measured using quantitative real-time PCR with specific primers. The data represent the mean ± SEM of target gene expression normalized to β-actin levels using the delta–delta Ct method. The experiments were independently replicated three times. Statistical analysis was performed using the Kruskal–Wallis test (n.s). D Zebrafish BMI and blood glucose levels were analyzed and compared with the control group following RSD induction. The height and weight of fish were measured to calculate BMI using the formula BMI = mg/cm2. Blood glucose levels were measured from the zebrafish tail blood samples. The values are displayed as the mean ± SEM, and individual values are represented by dots (n = 30 ~ 36/group). Statistical analysis was performed using the Mann–Whitney test (n.s)