Korean J Obstet Gynecol.
1999 May;42(5):1024-1029.
Regulation of Oxytocin Receptor by Interleukin-6 on Cultured Myometrial Cells
Abstract
OBJECTIVE
Inflammatory cytokines seem to play a key role in mechanisms initiating labor. The objective of this study was to assess the effects of interleukin[Il]-6 on expression of human myometrial oxytocin receptors.
METHODS
We prepared a human myometrial cell culture system. Myometrial cells collected from 12 patients were treated with Il-6 of different concentrations[10-7, 10-9, 10-12M] for 3 days and oxytocin receptor protein was determined by Western blotting. To demonstrate oxytocin receptor messenger RNA, reverse transcription-polymerase chain reaction was performed.
RESULTS
Western blotting showed a single 70-kd band corresponding to the oxytocin receptor. Treatment with higher concentration[10-7, 10-9M] of Il-6 led to a significant increase in myometrial oxytocin receptor protein levels[p=0.001, 0.002 respectively]. However, treatment with lower concentration[10-12M] did not increase oxytocin receptor levels[p=0.1]. Reverse transcription-polymerase chain reaction showed oxytocin receptor messenger ribonucleic acid as a 391-bp band.
CONCLUSION
In cultured myometrial cells, Il-6 increase significantly oxytocin receptor protein level. This study has added further support to the notion that the myometrium serves as a target for the inflammatory cytokine, Il-6, thus promoting preterm labor associated with intrauterine infection.