Figure 2. Effects of STP on the meiotic progression of HU-exposed oocytes. (A) Representative images of oocytes which underwent GVBD (germinal vesicle breakdown) in control, HU-exposed and STP-supplemented groups. Scale bar, 120 μm. (B) The rates of GVBD were recorded in control, HU-exposed, and STP-supplemented oocytes. (C) Representative images of oocytes which extruded the first polar body (PB1) in control, HU-exposed and STP-supplemented groups. Scale bar, 120 μm. (D) The rates of PBE (polar body extrusion) were recorded in control, HU-exposed, and STP-supplemented oocytes. Data of (B, D) were presented as mean percentage (mean ± SEM) of at least three independent experiments. *P < 0.05.