Maternal intravenous administration of long chain n-3 polyunsaturates to the pregnant ewe in late gestation results in specific inhibition of prostaglandin H synthase (PGHS) 2, but not PGHS1 and oxytocin receptor mRNA in myometrium during betamethasone-induced labor

Xiao Hong Ma, Wen Xuan Wu, J. Thomas Brenna, Peter W. Nathanielsz

Research output: Contribution to journalArticle

13 Scopus citations

Abstract

OBJECTIVES: Both the onset of labor and time to delivery during betamethasone-induced delivery are delayed by omega-3 polyunsaturated fatty acid (PUFA) administration to pregnant sheep. That fatty acid also inhibits the labor-related increase in maternal plasma estradiol and maternal and fetal prostaglandin E2. To evaluate the mechanism of inhibition of prostaglandin production and delay of onset of labor and time of delivery in PUFA-treated sheep, we determined the effect of PUFA on myometrial prostaglandin H synthase (PGHS) 1 and 2 and oxytocin receptor mRNA levels in betamethasone-induced labor. METHODS: At 124 days' gestation, a 20% emulsion of either intralipid (IL, n = 6) or PUFA (n = 6) was infused continuously (3 mL/kg per day) intravenously (IV) to the ewe. At 125 days' gestation, betamethasone was administered IV (10 μg/h over 48 hours) to fetuses of both intralipid- and PUFA-treated ewes. Myometrium was collected at necropsy either during betamethasone-induced labor as evaluated by myometrial electromyography or within 5 days of the termination of betamethasone infusion, if delivery did not occur after fetal betamethasone infusion. Total myometrial RNA was analyzed by Northern blot for oxytocin receptor and PGHS1 and 2 mRNA normalized for 18s. RESULTS: Treatment with PUFA decreased myometrial PGHS2 mRNA but did not alter myometrial PGHS1 and oxytocin receptor mRNA after betamethasone administration. CONCLUSIONS: This finding provides a mechanism whereby PUFA delays betamethasone-induced delivery in sheep and suggests a potential role of PUFA as an effective tocolytic agent in human pregnancy. Copyright (C) 2000 by the Society for Gynecologic Investigation.

Original languageEnglish (US)
Pages (from-to)233-237
Number of pages5
JournalJournal of the Society for Gynecologic Investigation
Volume7
Issue number4
DOIs
StatePublished - Jul 2000
Externally publishedYes

Keywords

  • And parturition
  • Myometrium
  • Oxytocin receptor
  • Polyunsaturated fatty acids
  • Prostaglandin H synthase
  • Sheep

ASJC Scopus subject areas

  • Obstetrics and Gynecology

Fingerprint Dive into the research topics of 'Maternal intravenous administration of long chain n-3 polyunsaturates to the pregnant ewe in late gestation results in specific inhibition of prostaglandin H synthase (PGHS) 2, but not PGHS1 and oxytocin receptor mRNA in myometrium during betamethasone-induced labor'. Together they form a unique fingerprint.

Cite this