Figure 5.

Figure 5.

DNA damage in zebrafish testes exposed to DBDPE in vivo. (A) DNA damage in zebrafish testes detection by immunofluorescence staining against the histone protein γ-H2AX. The representative images show DAPI-stained (blue) nuclei with nuclear γ-H2AX foci in red. Scale bar: 20μm. (B) Representative positive signals detected in SPD (indicated by white bold arrow), SPC-I (indicated by white dashed arrow; zygotene spermatocytes, signals dispersed within the nucleus), and SPC-II (indicated by white thin arrow; leptotene spermatocytes, strong signals concentrated within in the nucleus). (C) Ratio of fluorescence intensity of γ-H2AX to the corresponding fluorescence intensity of DAPI in SPD. (D) Ratio of fluorescence intensity of γ-H2AX signals to the corresponding fluorescence intensity of DAPI in SPC-I. (E) Ratio of fluorescence intensity of γ-H2AX signals to the corresponding fluorescence intensity of DAPI in SPC-II. Results are represented as means±standard errors of the mean (SEMs), n=6 testes. Data are reported in Excel Table S5. Note: DAPI, 4′,6-diamidino-2′-phenylindole; DBDPE, decabromodiphenyl ethane; SPC, spermatocytes; SPD, spermatozoa. *p<0.05, **p<0.01, and ***p<0.001 indicate significant differences between exposure and control groups, by one-way analysis of variance (ANOVA) followed by the post hoc least significant difference (LSD) test.