We investigated the expression and localization of natriuretic peptide receptor 2 (Npr2) in mouse oocytes and pre-implantation embryos. Immunocytochemistry and quantitative real-time polymerase chain reaction (qRT-PCR) were performed on mouse oocytes and embryos at different developmental stages. Npr2 was expressed in all oocyte and pre-implantation embryo stages analyzed. Germinal vesicle oocytes exhibited greater Npr2 expression than metaphase II oocytes. In pre-implantation embryos, Npr2 expression was significantly greater from the 2-cell stage to the blastocyst stage than for the zygote. Npr2 expression at the blastocyst stage was significantly less than at the morula stage. We found that Npr2 is expressed not only in mouse oocytes, but also in mouse embryos. Npr2 may play an important role in early embryonic development and embryo implantation.
Keywords: C-type natriuretic peptide; embryo; mice; natriuretic peptide receptor 2; oocyte.