Effect of relaxin and IGF-I on the pre-implantation development of Mongolian gerbil (Meriones unguiculatus) embryos in vitro

Purpose Both relaxin and insulin-like growth factor (IGF) are members of the insulin super family. This study aimed to investigate the effect of relaxin and IGF-I on the pre-implantation of Mongolian gerbil of blastocyst development in vitro. Methods Blastocysts and eight-cell stage embryos were collected from female gerbils. Eight-cell embryos and blastocysts were cultured in mM16 medium supplemented with or without relaxin or IGF-I for 24 h. Blastocysts were counted for total, inner cell mass (ICM) and trophectoderm (TE) cell numbers, and assessed apoptosis incidence. In addition, to measure incorporation of 3 H-methionine, blastocysts were cultured for 3 h with relaxin or IGF-I, washed with trichloroacetic acid and measured by liquid scintiration counter. Results Relaxin (200 ng/ml) increased total, TE and ICM cell numbers of blastocyst ( P