Figure 1. Concentration-dependent effect of NAC on spindle morphology in post-ovulatory oocytes aging for 24h in vitro. Oocytes cultured with different concentrations of NAC for 24h in vitro were collected for immunofluorescence analysis. Oocytes with normal spindles and those showing abnormal spindles were counted to calculate the percentage of abnormal spindles. X-axis represents the concentrations of NAC. NC, the oocyte without NAC treatment. Y-axis represents the percentages of oocytes with abnormal morphological spindle. Data are expressed as mean ± SEM of at least 3 independent experiments, and 6 superovulated mice were killed to obtain a minimum of 40 oocytes for each experiment. Star represents mean differ 0.01< p < 0.05.