Effects of intrauterine IL-6 and IL-8 on the expression of surfactant apoprotein mRNAs in the fetal rat lung.
OBJECTIVE
The purpose of this study was to investigate the effect of interleukin-6 (IL-6) and interleukin-8 (IL-8), whose concentrations are elevated with chorioamnionitis, on the expression of surfactant apoprotein mRNAs in fetal rat lung.


METHODS
We employed an animal model in which we were able to administer substances continuously into the cavity between the fetal membranes and endometrium using a miniosmotic pump. Lipopolysaccharide (LPS), IL-6, or IL-8 was administered to timed pregnant rats for 3 days (day 16-19), and fetal lung expression of surfactant apoprotein mRNAs for SP (surfactant apoprotein)-A, SP-B, and SP-C was evaluated by Northern blot hybridization.


RESULTS
Continuous administration of LPS increased the expression of each surfactant apoprotein mRNA, but the expression of mRNAs was not dose-dependent. On the other hand, continuous IL-6 or IL-8 administration increased the expression of each surfactant apoprotein mRNA in a dose-dependent manner.


CONCLUSIONS
Fetal lung maturation may be promoted by either IL-6 or IL-8 produced in response to chorioamnionitis.
Ikegami
T
T
Department of Obstetrics and Gynecology, Akita University School of Medicine, 1-1-1 Hondo, 010, Akita, Japan.
Tsuda
A
A
Karube
A
A
Kodama
H
H
Hirano
H
H
Tanaka
T
T
D000818:Animals; D015152:Blotting, Northern; D005260:Female; D015870:Gene Expression; D006801:Humans; D015850:Interleukin-6 / Q000008:administration & dosage* / Q000494:pharmacology; D016209:Interleukin-8 / Q000008:administration & dosage* / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology; D008168:Lung / Q000196:embryology* / Q000378:metabolism; D011247:Pregnancy; D011510:Proteolipids / Q000235:genetics; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; D011510:Proteolipids; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D012333:RNA, Messenger