Chorioamnionitis induced by subchorionic endotoxin infusion in sheep.
OBJECTIVE
This study was undertaken to determine whether subchorionic endotoxin infusion causes chorioamnionitis and preterm lung maturation, as occurs after intra-amniotic endotoxin.


METHODS
From day 118 of pregnancy, sheep received infusions of endotoxin (subchorionic 7.5 mg/d, n=11; intra-amniotic 2.5 mg/d, n=9) until delivery of lambs at 120 or 124 days. Other sheep received a single intra-amniotic injection of endotoxin (10 mg, n=7) at 118 days before delivery at 124 days. Controls (n=9) received equivalent saline solution treatments.


RESULTS
Chorioamnionitis accompanied all endotoxin treatments. Lung inflammation occurred after intra-amniotic endotoxin infusion or injection but not after subchorionic endotoxin. Umbilical arterial pH was lower and Pco(2) was higher than control after subchorionic endotoxin. Lung compliance and surfactant were increased after intra-amniotic endotoxin infusion or injection but not after subchorionic endotoxin.


CONCLUSIONS
Chorioamnionitis may result from inflammatory stimuli at various intrauterine sites, with different sites causing different fetal effects and not all cases of chorioamnionitis being accompanied by enhanced lung maturation.
Moss
Timothy J M
TJ
Lotteries Commission Perinatal Research Laboratories, School of Women's and Infants' Health, University of Western Australia, Box M094, 35 Stirling Highway, Crawley, WA 6009, Australia. tmoss@cyllene@uwa.edu.au
Nitsos
Ilias
I
Newnham
John P
JP
Ikegami
Machiko
M
Jobe
Alan H
AH
D000650:Amnion / Q000187:drug effects*; D000653:Amniotic Fluid / Q000737:chemistry; D000704:Analysis of Variance; D000818:Animals; D002821:Chorioamnionitis / Q000150:complications; D004195:Disease Models, Animal; D005314:Embryonic and Fetal Development / Q000187:drug effects*; D004731:Endotoxins / Q000494:pharmacology*; D005260:Female; D007267:Injections; D011014:Pneumonia / Q000175:diagnosis*; D011247:Pregnancy; D011270:Pregnancy, Animal; D011336:Probability; D011897:Random Allocation; D012016:Reference Values; D034561:Sheep, Domestic
D004731:Endotoxins