title: Effects of subcutaneous LPS injection on gestational length and intrauterine and neonatal mortality in mice.
abstract: BACKGROUND
  Infection during pregnancy can predispose offspring to develop various psychiatric disorders such as depression in later life. In order to investigate the potential mechanisms underlying these associations, animal models of maternal infection have been employed. As such, lipopolysaccharide (LPS) has been commonly used to mimic a bacterial infection in pregnant mice.
  
  
  OBJECTIVE
  The original aim of our study was to investigate the effects of different doses of subcutaneous LPS administration on affective behavior in adult mouse offspring. In the present paper, however, we report that subcutaneous LPS administration has a profound impact on gestational length, litter size, and perinatal mortality in the offspring, even at a relatively low dose.
  
  
  METHODS
  Pregnant mice were randomly divided into 3 groups, receiving either a high (2 mg/kg) or a low (0.5 mg/kg) dose of LPS or phosphate-buffered saline by means of subcutaneous injection. Subsequently, the effects on gestational length, litter size, and perinatal mortality in the offspring were assessed.
  
  
  RESULTS
  After subcutaneous injection with a high dose of LPS, we observed a significant decrease in gestational length and an increase in neonatal mortality. When the low dose was administered, a tendency towards a reduced litter size was observed, most likely reflecting increased intrauterine mortality in response to prenatal maternal LPS exposure.
  
  
  CONCLUSIONS
  We showed that subcutaneous administration of 2 mg/kg LPS to pregnant mice in the last phase of gestation should be avoided because of high offspring mortality rates, whereas subcutaneous injection of 0.5 mg/kg LPS seems to result in reabsorption of the fetuses.
authors.affiliation: School for Mental Health and Neuroscience (MHeNS), Department of Psychiatry and Neuropsychology, Maastricht University Medical Centre+, Maastricht, The Netherlands.
authors.forename: Yara
authors.initials: Y
authors.lastname: Pujol Lopez
authors.forename: Harry W M
authors.initials: HW
authors.lastname: Steinbusch
authors.forename: Bart
authors.initials: B
authors.lastname: Rutten
authors.forename: Gunter
authors.initials: G
authors.lastname: Kenis
authors.forename: Daniel L
authors.initials: DL
authors.lastname: van den Hove
authors.forename: Aye M
authors.initials: AM
authors.lastname: Myint
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D005260:Female; D005313:Fetal Death; D007249:Inflammation / Q000150:complications*; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D008098:Litter Size; D051379:Mice; D008810:Mice, Inbred C57BL; D011247:Pregnancy; D011248:Pregnancy Complications; D011251:Pregnancy Complications, Infectious; D011897:Random Allocation
chemical_list: D008070:Lipopolysaccharides