Progesterone regulation of glutathione S-transferase Mu2 expression in mouse uterine luminal epithelium during preimplantation period

Objective: To investigate the differential expression and regulation of Gstm2 in mouse uterus during early pregnancy. Design: Experimental animal study. Setting: University research laboratory. Animal(s): Sexually mature female Kunming white strain mice. Intervention(s): Delayed and activated implantaton, pseudopregnancy, hormonal treatment. Main Outcome Measure(S): The expression of Gstm2 mRNA was detected by in situ hybridization and reverse-transcription polymerase chain reaction (RT-PCR). Result(s): By in situ hybridization, there were a low level of Gstm2 expression in luminal epithelium on day 3 and a strong level in the luminal epithelium on day 4 during early pregnancy. The expression pattern of Gstm2 in the pseudopregnant uterus was similar to that during early pregnancy By RT-PCR, Gstm2 was strongly detected in the uteri on days 3 and 4 of pregnancy and pseudopregnancy. Gstm2 expression was strongly detected in the luminal epithelium under delayed implantation, but not seen after delayed implantation was activited by estrogen. In the ovariectomized mouse uterus, Gstm2 expression was strongly upregulated by progesterone via progesterone receptor. Conclusion(S): The results showed that Gstm2 was highly expressed in the uterine luminal epithelium during preimplantation period and up-regulated by progesterone. (Fertil Steril (R) 2009;91:2123-30. (C)2009 by American Society for Reproductive Medicine.)