To contract or not: A key question for the uterine muscles in pregnancy

November 20, 2008

During pregnancy, the muscles of the uterus are relatively inactive. A switch to an activated state capable of strong contractions is therefore essential prior to the onset of labor. Kathleen Martin and colleagues, at Dartmouth Medical School, Lebanon, have now provided new insight into the events that prime the uterine muscles for contraction, something that they hope might have implications for the development of therapies for preterm labor (i.e., labor that occurs before 37 weeks of pregnancy), the most serious complication of pregnancy in developed countries.

In the study, when the protein IP on the surface of muscle cells in human uterine tissue strips obtained from pregnant women undergoing Caesarean delivery prior to the onset of natural labor was stimulated by agonist chemicals, it induced the upregulation of proteins involved in muscle contraction. Further, the same chemicals increased the contraction of these tissue strips in response to the hormone oxytocin. The authors therefore conclude that the molecule that normally binds IP in vivo, prostacyclin, primes the muscles in the human uterus, allowing for strong contractions during labor. As Michael Taggart, at Newcastle University, United Kingdom, and colleagues discuss in an accompanying commentary, these data might be viewed by many as contentious, because prostacyclin is a smooth muscle relaxant. However, they do provide an explanation for the paradoxical observation that one of the major signaling molecules produced by the uterus just prior to labor is prostacyclin.
-end-
TITLE: Prostacyclin primes pregnant human myometrium for an enhanced contractile response in parturition

AUTHOR CONTACT:
Kathleen A. Martin
Dartmouth Medical School, Lebanon, New Hampshire, USA.
Phone: (603) 650-7439; Fax: (603) 650-4928; E-mail: kathleen.a.martin@dartmouth.edu.

View the PDF of this article at: https://www.the-jci.org/article.php?id=33800

ACCOMPANYING COMMENTARY
TITLE: Possible dual roles for prostacyclin in human pregnancy and labor

AUTHOR CONTACT:
Michael J. Taggart
Newcastle University, Newcastle upon Tyne, United Kingdom.
Phone: 44-191-222-6988; Fax: 44-191-222-5066; E-mail: Michael.taggart@ncl.ac.uk.

View the PDF of this article at: https://www.the-jci.org/article.php?id=37785

JCI Journals

Related Pregnancy Articles from Brightsurf:

COVID-19 has a prolonged effect for many during pregnancy
Symptoms for pregnant women with COVID-19 can be prolonged, lasting two months or longer for a quarter of the women who participated in a national study led by UC San Francisco and UCLA.

Relaxed through pregnancy
A group of researchers from Charité - Universitätsmedizin Berlin have been able to show that maternal psychological wellbeing during pregnancy has a positive effect on newborn infants.

Trajectories of antidepressant medication use during pregnancy
In an analysis of women who started pregnancy when taking antidepressant medications, investigators identified three trajectories of antidepressant dispensing during pregnancy: more than half stopped their treatment, a quarter maintained their treatment throughout pregnancy, and one-fifth discontinued it for a minimum of three months and then resumed it during the postpartum period.

Are women using e-cigarettes during preconception and/or pregnancy?
A new study of 1,365 racially/ethnically diverse, low-income pregnant women found that 4% reported e-cigarette use.

A better pregnancy test for whales
To determine whale pregnancy, researchers have relied on visual cues or hormone tests of blubber collected via darts, but the results were often inconclusive.

Cannabis use during pregnancy
The large health care system Kaiser Permanente Northern California provides universal screening for prenatal cannabis use in women during pregnancy by self-report and urine toxicology testing.

Questions and answers about cannabis use during pregnancy
A new study shows that women have many medical questions about the use of cannabis both before and during pregnancy, and during the postpartum period while breastfeeding.

The effect of taking antidepressants during pregnancy
Exposure to antidepressants during pregnancy and the first weeks of life can alter sensory processing well into adulthood, according to research in mice recently published in eNeuro.

Is ivermectin safe during pregnancy?
Is it safe to give ivermectin to pregnant women? To answer this question, researchers from the Barcelona Institute for Global Health (ISGlobal), an institution supported by 'la Caixa,' conducted a systematic review and meta-analysis of studies that reported cases of accidental exposure to the drug among pregnant women.

Going to sleep on your back in late pregnancy
This study looked at whether going to sleep on your back in the third trimester of pregnancy was associated with average lower birth weights.

Read More: Pregnancy News and Pregnancy Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.