Figure 4. Epitalon protected the function of mitochondria during post-ovulatory oocyte aging in vitro. (A) Distribution of mitochondria with high membrane potential (red) and low membrane potential (green) in three groups of oocytes. (B) The fluorescence intensity of ratio of red/green fluorescence analysis for each oocyte was conducted using Image J software. Significant difference between the Aged and 0.1mM Epitalon-treated groups was observed (p < 0.01). (C) mtDNA copy numbers of MII oocytes in all three groups were revealed by real-time polymerase chain reaction analysis. Data from more than 30 oocytes were analyzed for each group. Significant difference between the Aged and 0.1mM Epitalon-treated groups was observed (p < 0.01). Data are expressed as mean ± SEM of at least three independent experiments. Scale bar: 100 μm.