title: Effects of epidermal growth factor on preimplantation mouse embryos.
abstract: OBJECTIVE
  Our purpose was to clarify the effects of epidermal growth factor (EGF) on mouse preimplantation embryos.
  
  
  METHODS
  We examined the effect of EGF on two-cell and four-cell stage mouse embryos cultured in vitro. In preimplantation embryos, we analyzed the binding of 125I-EGF by autoradiography and EGF receptor mRNA by the reverse transcription-polymerase chain reaction.
  
  
  RESULTS
  At more than 0.005 ng/ml, EGF relieved the two-cell block and regulated the differentiation of morula-stage embryos. These effects were negated by antiserum. EGF did not exhibit any marked effect on embryos between the four-cell and the morula stages. Specific binding for EGF and EGF receptor mRNA was detected during and after the morula stage.
  
  
  CONCLUSIONS
  The effects of EGF on preimplantation mouse embryos differed according to the stage of development, promoting cleavage before the four-cell stage and regulating differentiation after the morula stage. This regulatory action is thought to be transmitted to the cells via EGF receptors.
authors.affiliation: Department of Obstetrics and Gynecology, Mie University School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Terada
authors.forename: H
authors.initials: H
authors.lastname: Minoura
authors.forename: N
authors.initials: N
authors.lastname: Toyoda
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D015139:Blotting, Southern; D002454:Cell Differentiation / Q000187:drug effects; D002970:Cleavage Stage, Ovum / Q000187:drug effects; D003470:Culture Media; D046508:Culture Techniques; D017931:DNA Primers / Q000737:chemistry; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D066246:ErbB Receptors / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D007457:Iodine Radioisotopes; D051379:Mice; D008813:Mice, Inbred ICR; D008853:Microscopy; D009028:Morula / Q000187:drug effects / Q000502:physiology; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D003470:Culture Media; D017931:DNA Primers; D007457:Iodine Radioisotopes; D012333:RNA, Messenger; D004815:Epidermal Growth Factor; D066246:ErbB Receptors