• Embryo-derived PAF;
  • fertilization;
  • implantation

PROBLEM: This study measured platelet-activating factor (PAF) production of in vitro and in vivo fertilized murine embryos to ascertain whether site of fertilization impacted subsequent embryonic PAF production.

METHOD: Ooocytes and embryo were collected from stimulated B6D2F1 mice. PAF production throughout the preimplantation phase from the two-celled stage through expanded blastocysts was measured and compared among normally developing embryos with the only difference being site of fertilization.

RESULTS: A striking increase in PAF production was noted for both in vivo and in vitro fertilized embryos over the four days of culture. Significantly higher (P<.001) levels of PAF production were noted with development from the two-celled stage (47.22 ± 4.13; 44.30 ± 2.43) to expanded blastocysts (254.31 ± 24.01;255.11 ± 5.35 ng/embryo/24h)forbothin vitro and in vivo fertilized embryos, respectively. There was no significant difference (P>.05) in PAF production between the two groups of embryos.

CONCLUSIONS: Embryonic PAF production in the mouse increases in a stage-specific manner, and specifically the site of fertilization in vitro versus in vivo does not affect PAF production in normally developing embryos.