Figure 1

Narfl Deficiency Leads to Abnormal Behavior and Abnormal Blood Vessels and Neurons in Zebrafish. A) Swimming behavior trajectories of zebrafish with different genotypes under normal light. B) Swimming behavior analysis of zebrafish with different genotypes within 60 min under normal light, including total swimming distance, average swimming speed and burst duration analysis (n = 10). C) Toluidine blue staining was used to detect the morphology of Nissle bodies in the brain of zebrafish with different genotypes. D) Transmission electron microscopy (TEM) analysis of the blood‐brain barrier (BBB) ultrastructure in zebrafish revealed distinct morphological differences between wild‐type and narfl^−/− mutants. In wild‐type zebrafish, endothelial cells appeared plump with no signs of shrinkage, and the basement membrane maintained structural integrity. In contrast, narfl^−/− zebrafish exhibited pronounced shrinkage of BBB endothelial cells, accompanied by distension and fragmentation of the basement membrane. The field of view of BBB ultrastructure in the brain of zebrafish with different genotypes was observed by transmission electron microscopy (TEM), at 1500×, 5000×, and 10000×, respectively. E) The cerebral vascular morphology of zebrafish with different genotypes was observed by fluorescence inverted microscope imaging system (dorsal view). F) Fluorescence confocal microscope observation and quantitative analysis of zebrafish vascular segments showed that narfl^−/− dorsal longitudinal anastomosis with blood vessels (DLAV) and the junction cells were obviously absent. G) narfl^−/−zebrafish dorsal longitudinal cardinal vessels (PCV), connective cells were disordered or even absent, and the structures of dorsal aorta (DA) and PCV were obviously disordered and distorted (n = 5). Statistical significance was assessed using one‐way ANOVA with Tukey's multiple comparison test was used in panels B, F and G. ns, not significant; *p < 0.05; **p < 0.01; ***p < 0.001.