Fig. 2

Representative histological changes of brain tissue samples and changes of related parameters. A TEM of the blood–brain barrier (2 μm), a, b, c, d, e, and f represent the group of 0 − , 0 + , 15 − , 15 + , 150 − , and 150 + , respectively. The blue arrow represents the basement membrane of the blood–brain barrier. B The number of entries to the top. C Latency to entry the top half. D Active time. E Distance moved. F, G, and H represent the content of 5-HT, GABA, and DA in zebrafish brain samples. I The activity of SOD in zebrafish intestinal samples. Data are expressed as means ± SD. *p < 0.05 indicate significant differences between exposure groups and the control group. #p < 0.05 indicate significant differences between vitamin D-high and vitamin D-low groups at the same PS-NPs concentration