title: Primate preimplantation embryo is a target for relaxin during early pregnancy.
abstract: OBJECTIVE
  To determine whether preimplantation embryos are targets for relaxin secreted from the corpus luteum of the menstrual cycle.
  
  
  METHODS
  Rhesus monkey oocytes obtained from females undergoing controlled ovarian hyperstimulation were inseminated, and the resulting embryos were cultured in medium with or without recombinant human relaxin (20 ng/mL) for 8 days.
  
  
  METHODS
  Research laboratory.
  
  
  METHODS
  Rhesus monkey.
  
  
  METHODS
  Controlled ovarian stimulation to obtain oocytes for in vitro-produced embryos that were cultured with or without human recombinant relaxin.
  
  
  METHODS
  Rate of blastocyst development, percentage of blastocysts, and inner cell mass/trophectoderm cell ratio were measured on day 8 of culture. The presence of relaxin receptor (RXFP1) messenger RNA in eight-cell embryos was observed by array hybridization.
  
  
  RESULTS
  RXFP1 receptor expression was localized to the inner cell mass of blastocysts, as shown by immunohistochemistry. The percentage of embryos that developed to blastocyst and the inner cell mass/trophectoderm cell ratio was unchanged with relaxin supplementation; however, the relaxin-treated embryos developed into blastocysts significantly sooner than untreated embryos.
  
  
  CONCLUSIONS
  These results are the first evidence that the preimplantation primate embryo is a target for relaxin and that the addition of relaxin to in vitro culture medium enhances rhesus monkey embryo development.
authors.affiliation: California National Primate Research Center, University of California, Davis, CA 95616, USA. cavandevoort@ucdavis.edu
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Vandevoort
authors.forename: Namdori R
authors.initials: NR
authors.lastname: Mtango
authors.forename: Keith E
authors.initials: KE
authors.lastname: Latham
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Stewart
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000187:drug effects* / Q000378:metabolism*; D006224:Cricetinae; D016503:Drug Delivery Systems / Q000379:methods*; D046149:Embryo Culture Techniques / Q000379:methods; D005260:Female; D006801:Humans; D008253:Macaca mulatta; D011247:Pregnancy; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D018000:Receptors, Peptide / Q000378:metabolism; D012065:Relaxin / Q000008:administration & dosage* / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D043562:Receptors, G-Protein-Coupled; D018000:Receptors, Peptide; C033395:relaxin receptors; D012065:Relaxin