title: Time-dependent effect of in utero inflammation: a longitudinal study in rats.
abstract: OBJECTIVE
  To determine the impact of the duration of fetal exposure to inflammation on the neurological outcome of pups.
  
  
  METHODS
  Time-pregnant Sprague-Dawley rats (n = 32) received intraperitoneal injection of lipopolysaccharides (LPS; 500 µg/kg), or an equivalent volume of vehicle 3, 6, 12 and 24 h before C-section. Maternal serum and amniotic fluid were tested for cytokines. Motor activity of resuscitated pups (n = 58) was analyzed using the open-field test (20 d). Brains were collected for histopathological examination.
  
  
  RESULTS
  Perinatal mortality increased with the duration of fetal exposure to LPS. All parameters tested with the open-field test were lower in the LPS 12 h exposure group compared to the control group (p < 0.05). Tissue inhibitor of metalloproteinase 1 (TIMP-1) was statistically increased in maternal blood after 3, 6 and 12 h of LPS injection (p < 0.05 versus control).
  
  
  CONCLUSIONS
  A threshold of duration of exposure to inflammation is demonstrated, before which delivery should be performed in order to prevent brain damage.
authors.affiliation: Department of Obstetrics and Gynecology, CRC E-Lebel - CHUS, Université de Sherbrooke, Sherbrooke, QC, Canada.
authors.forename: Marie-Ève
authors.initials: MÈ
authors.lastname: Roy-Lacroix
authors.forename: Maxime
authors.initials: M
authors.lastname: Guérard
authors.forename: Maryse
authors.initials: M
authors.lastname: Berthiaume
authors.forename: Marek
authors.initials: M
authors.lastname: Rola-Pleszczynski
authors.forename: Ana-Maria
authors.initials: AM
authors.lastname: Crous-Tsanaclis
authors.forename: Jean-Charles
authors.initials: JC
authors.lastname: Pasquier
mesh_terms: D000818:Animals; D002821:Chorioamnionitis / Q000401:mortality / Q000473:pathology* / Q000503:physiopathology; D002658:Developmental Disabilities / Q000209:etiology; D004195:Disease Models, Animal; D005260:Female; D009422:Nervous System Diseases / Q000401:mortality / Q000473:pathology* / Q000503:physiopathology; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors