title: Pinopodes are present in Lif null and Hoxa10 null mice.
abstract: OBJECTIVE
  To assess pinopode formation in Lif null and Hoxa10 null mice with infertility secondary to failed implantation.
  
  
  METHODS
  Controlled animal experiment.
  
  
  METHODS
  Animal research and laboratory facility.
  
  
  METHODS
  Lif null, Hoxa10 null, and ICR mice and Sprague-Dawley rats.
  
  
  METHODS
  Endometrial tissue was collected during the peri-implantation period and after ovariectomy.
  
  
  METHODS
  Endometrial epithelial tissue was examined under scanning-electron microscopy and assigned a score depending on the number of pinopodes present.
  
  
  RESULTS
  Pinopode scores in ICR, Lif null, and Hoxa10 null mice were comparable throughout the peri-implantation period, rising on day 3.5 of pregnancy and remaining elevated through to day 7.5, suggesting that pinopodes are not a good indicator of receptivity in mice. In contrast, pinopode scores in rats clearly demarcated the window of receptivity, appearing on day 4 of pregnancy and declining sharply on day 6. Pinopode scores were low in E(2)-treated ovariectomized mice, but unexpectedly, pinopode scores in vehicle-injected ovariectomized ICR mice were markedly elevated.
  
  
  CONCLUSIONS
  Lif null and Hoxa10 null mice, in which implantation is impaired, have a similar number of pinopodes to fertile ICR mice. Pinopodes do not define a window of implantation in mice.
authors.affiliation: Division of Reproductive Sciences, Samuel Lunenfeld Research Institute, and the Fran and Lawrence Bloomberg Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Institute of Medical Sciences, Toronto, Ontario, Canada.
authors.forename: Claire E
authors.initials: CE
authors.lastname: Quinn
authors.forename: Jacqui
authors.initials: J
authors.lastname: Detmar
authors.forename: Robert F
authors.initials: RF
authors.lastname: Casper
mesh_terms: D000818:Animals; D021961:Cell Membrane Structures / Q000502:physiology / Q000648:ultrastructure*; D004717:Endometrium / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure*; D004848:Epithelium / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D005298:Fertility / Q000502:physiology; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D053605:Leukemia Inhibitory Factor / Q000172:deficiency* / Q000235:genetics / Q000502:physiology; D051379:Mice; D008813:Mice, Inbred ICR; D018345:Mice, Knockout; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins; C507837:LIF protein, human; D053605:Leukemia Inhibitory Factor; C069634:HOXA10 protein, human