Comparison of the effect of the three types of rat medicated serums on gene expressions. Significant differences in the mRNA levels of Oct4, SSEA-1, Stella, Blimp1, Prdm14, and Tfap2c can be seen on day 7, with the highest expression seen in the stem cells treated with the rat medicated serum containing ZGW. No significant difference in any of the gene expressions was found on day 24, except for Tfap2c. On day 24, the mRNA levels of SCP3 and GDF-9 in the rat medicated serum containing ZGW were higher than the mRNA levels of SCP3 and GDF-9 in the other two types of rat medicated serums. No significant differences in mRNA levels of ZP-1, ZP-2, and ZP-3 were detected among the three types of rat medicated serums.