Expression of growth hormone receptor in mouse preimplantation embryos.

Growth hormone (GH) is believed to be involved in reproductive function. Recent reports demonstrate the presence of the growth hormone receptors (GHR) in reproductive organs and fetal tissues suggesting that the contribution of GH to reproductive phenomena may be mediated through GHR. In this study we assessed the expression of GHR in mouse preimplantation embryos using immunofluorescent staining with a monoclonal antibody directed against GHR. The messenger RNA (mRNA) for GHR was investigated in mouse preimplantation embryo by reverse transcription-polymerase chain reaction (RT-PCR). The anti-GHR monoclonal antibody Mab 263 was detected by immunofluorescent staining after the compaction of the morula stage. GHR mRNA transcript was identified in 8-cell stage embryos. Our findings indicate that GHR is localized in mouse preimplantation embryos, and suggests that GH has a direct effect on preimplantation embryos mediated by GHR.