title: Unique uterine localization and regulation may differentiate LPA3 from other lysophospholipid receptors for its role in embryo implantation.
abstract: OBJECTIVE
  To determine factors differentiating LPA3 from other lysophospholipid (LP) receptors for its role in embryo implantation.
  
  
  METHODS
  Experimental mouse models.
  
  
  METHODS
  Institute/university research laboratories.
  
  
  METHODS
  Wild-type, Lpar3(-/-), Lpar1(-/-)Lpar2(-/-), and S1pr2(-/-)S1pr3(-/-) mice.
  
  
  METHODS
  Ovariectomy.
  
  
  METHODS
  Blue dye injection for determining implantation sites on gestation day 4.5. Real-time polymerase chain reaction for measuring gene expression in whole uterus and separated uterine layers. In situ hybridization for detecting progesterone (P)-induced Lpar3 expression in the uterine luminal epithelium (LE).
  
  
  RESULTS
  Normal implantation was observed in Lpar1(-/-)Lpar2(-/-) and S1pr2(-/-)S1pr3(-/-) females. Temporal expression showed peak expression of Lpar3 in the preimplantation uterus and constitutive expression of the other nine LP receptors in the periimplantation uterus. Spatial localization revealed main expression of Lpar3 in the LE and broad expression of the remaining LP receptors in all three main uterine layers: LE, stromal, and myometrial layers. Hormonal regulation in ovariectomized uterus indicated up-regulation of Lpar3 but down-regulation or no effect of the remaining nine LP receptors by P, and down-regulation of most LP receptors, including Lpar3, by 17β-estradiol.
  
  
  CONCLUSIONS
  LE localization and up-regulation by P differentiate LPA3 from the other nine LP receptors and may underlie its essential role in embryo implantation.
authors.affiliation: Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602, USA. ye@uga.edu
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Ye
authors.forename: Deron R
authors.initials: DR
authors.lastname: Herr
authors.forename: Honglu
authors.initials: H
authors.lastname: Diao
authors.forename: Richard
authors.initials: R
authors.lastname: Rivera
authors.forename: Jerold
authors.initials: J
authors.lastname: Chun
mesh_terms: D000818:Animals; D010064:Embryo Implantation / Q000235:genetics* / Q000502:physiology; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005865:Gestational Age; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D011247:Pregnancy; D011374:Progesterone / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D049368:Receptors, Lysophosphatidic Acid / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014018:Tissue Distribution; D014599:Uterus / Q000033:anatomy & histology* / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D049368:Receptors, Lysophosphatidic Acid; D011374:Progesterone