title: [The change of nitric oxide to PGE2 ratio in uterine tissues of endotoxin-treated pregnant mice].
abstract: OBJECTIVE
  To investigate the relationship between preterm labour and the ratio of nitric oxide to prostaglandin E2 in uterine tissues.
  
  
  METHODS
  Pregnant mice were given lipopolysaccharide(LPS), LPS + DETA/NO, LPS + DETA or saline solution respectively by intraperitoneal injection on day 16 of gestation. The delivery time of each mouse was recorded. Four separate groups of mice were given treatment as described. And they were killed at 12 hours after that. Serum progesterone, uterine production of nitrite and PGE2 were measured.
  
  
  RESULTS
  Uterin production of nitrite and PGE2 in LPS-treated mice was significantly higher than that in control mice. In contrast the ratio of nitrite to PGE2 decreased. Accompanied by the fall of serum progesterone level DETA/NO rather than DETA could partially reversed the changes.
  
  
  CONCLUSIONS
  Infection can induce preterm labor by altering the ratio of nitric oxide to PGE2. Nitric oxide can prevent the decrease of nitric oxide to PGE2 ratio possibly by attenuating the fall of serum progesterone. And it can prevent LPS-induced preterm labor.
authors.affiliation: Department of Obstetrios and Gynecology, West China Second Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Weiyue
authors.initials: W
authors.lastname: Zeng
authors.forename: Fang
authors.initials: F
authors.lastname: Yan
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D046508:Culture Techniques; D015232:Dinoprostone / Q000378:metabolism*; D005260:Female; D008070:Lipopolysaccharides; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009569:Nitric Oxide / Q000378:metabolism*; D007752:Obstetric Labor, Premature / Q000139:chemically induced / Q000378:metabolism*; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D014599:Uterus / Q000378:metabolism*
chemical_list: D008070:Lipopolysaccharides; D009569:Nitric Oxide; D011374:Progesterone; D015232:Dinoprostone