Fig. 2.

Fig. 2.

Effects of parental treatment on zebrafish embryo endocrine stress response. (A) Cortisol levels and (B) hsd11b2, hsd20b2 and abcb4 relative gene expression of ∼1 h post-fertilization (hpf) embryos derived from adult zebrafish exposed to either control or combined exposure conditions for 14 days. Cortisol levels were compared with a Mann–Whitney rank sum test (P=0.041). The gene expression values were normalized to the geometric mean of ef1α and rpl13a and the expression ratio for each gene is presented relative to the control treatment. Statistical differences between values were determined by two-tailed t-tests (hsd11b2: P=0.965; hsd20b2: P=0.002; abcb4: P=0.003). Differences between treatments for a given parameter are indicated by an asterisk. Data are medians and interquartile ranges in A and means±s.e.m. in B (hsd11b2, hsd20b2 and abcb4, n=5–7; cortisol, n=6).