Effect of IL-1beta and IL-6 on oxytocin secretion in human uterine smooth muscle cells.
OBJECTIVE
Infection-mediated preterm labor results in the production of inflammatory cytokines, including interleukin-1beta (IL-1beta) and interleukin-6 (IL-6). Oxytocin (OT) plays a key role in the process of labor. This study investigates the effect of IL-1beta and IL-6 on intra-and extracellular OT in human smooth muscle cells and evaluates IL-1beta induced changes in IL-6 production.


METHODS
Primary cultures of human myometrium, obtained from term pregnant women (n = 7) were incubated with either IL-1beta or IL-6 for 0-24 hr. Intra- and extracellular OT peptide concentrations were measured by radioimmunoassay and IL-6 mRNA and protein were evaluated by reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay.


RESULTS
Both, IL-1beta and IL-6 led to an increase in OT secretion, which was accompanied by a reduction of the intracellular OT peptide pool. IL-1beta significantly induced IL-6 mRNA expression and protein secretion, which did not further enhance IL-1beta induced OT secretion.


CONCLUSIONS
The induction of OT secretion by proinflammatory cytokines in human myometrium in vitro, supports the concept of a thus regulated infection-triggered preterm labor process in vivo.
Friebe-Hoffmann
U
U
Magee-Womens Research Institute and the Division of Maternal-Fetal Medicine, University of Pittsburgh School of Medicine, Pennsylvania 15213, USA.
Chiao
J P
JP
Rauk
P N
PN
D002478:Cells, Cultured; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D009215:Myometrium / Q000166:cytology / Q000378:metabolism*; D010121:Oxytocin / Q000187:drug effects* / Q000378:metabolism*; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D012333:RNA, Messenger
D007375:Interleukin-1; D015850:Interleukin-6; D012333:RNA, Messenger; D010121:Oxytocin