Figure 2

The effect of H₂S treatment on the early development of zebrafish embryos. (a,b) H₂S concentrations of 10–25 µM cause no changes in the morphology and minor decrease in the survival of zebrafish embryos, while the concentrations of 50–200 µM cause substantial increase in both the rate of malformation and mortality. Fertilized eggs were incubated in E3 water supplemented with 10–200 µM H₂S for 48 h. The survival and well-being of the embryos was followed for 48 h and compared to E3 treated group (control). n(Control) = 397, n(10 µM) = 358, n(25 µM) = 310, n(50 µM) = 130, n(100 µM) = 182, n(200 µM) = 208. (c) Comparative developmental stages of control (E3 treated) and H₂S treated embryos. Newly fertilized eggs were kept in E3 water with 200 µM H₂S and the development was followed by time-lapse imaging. Two representative images are shown for both treatments (control images on the left, H₂S treatment images on the right). (d) The times for the first, the second and the third cell division in H₂S treated and control (E3 treated) embryos. Error bars represent SD, *p < 0.05, **p < 0.01, ***p < 0.001.