Sodium azide s2002

Catalase activity was assayed by measuring the conversion of H₂O₂ into O₂ using a Clark‐type oxygen electrode connected to a biological oxygen monitor YSI 5300A (Yellows Springs, OH, USA), according to (Foster & Coetzee, 2016 (link)), with slight modification. Briefly, 0.5 mg of protein of muscle homogenate was resuspended in a 0.1 M potassium phosphate buffer (pH 7.6) at 25°C, and the trace was monitored for 1 min. Later, fresh 6 mM of H₂O₂ was added to the chamber, and the conversion of H₂O₂ to oxygen was recorded for 2 min. Finally, 1.0 mM of sodium azide (S2002, Sigma‐Aldrich, St. Louis, MO, USA) was added to the chamber. Catalase activity was calculated using bovine catalase as standard (expressed as AU/mg of protein).

Adults of the Tg(gsdf:GFP) zebrafish line were raised at 28 °C until adulthood (aged from 4 to 5 months) in the INRA-LPGP fish facility13 (link). For testes dissection, adult male zebrafish were euthanized by immersion in a lethal dose of 2-phenoxyethanol (0,8 mg/ml). Testes were fixed overnight at 4 °C by 4% paraformaldehyde (PFA) in 0,01 M phosphate buffer saline pH 7.4 (PBS). After washing in PBS, testes were conserved in PBS +0,05% (w/v) sodium azide (S2002, Sigma-Aldrich) at 4 °C.