Document Detail

Failure of magnesium sulfate infusion to inhibit uterine activity in pregnant sheep.
MedLine Citation:
PMID:  9240605     Owner:  NLM     Status:  MEDLINE    
OBJECTIVES: Our purpose was to determine the effect of magnesium sulfate infusion on nonlabor uterine contractures and corticotropin-induced preterm uterine contractions in pregnant sheep. STUDY DESIGN: Fetal and maternal vascular catheters and uterine electromyographic electrodes were surgically placed in 15 pregnant sheep between 118 and 125 days' gestation. After 3 to 5 days of recovery, magnesium sulfate was infused into 7 ewes with a 0.11 gm/kg bolus over 20 minutes, followed by 0.08 gm/kg/hr. In 8 animals labor was induced with use of an intrafetal corticotropin infusion, after which 4 ewes received magnesium sulfate and 4 received saline solution. Continuous recordings of uterine electromyographic activity, amniotic pressure, fetal heart rate, blood pressure, and tracheal pressure were made. Maternal and fetal magnesium, calcium, albumin concentrations, and blood gases were determined before and during the infusion. RESULTS: Maternal magnesium concentrations increased from an average of 0.94 +/- 0.03 mmol/L to 2.73 +/- 0.1 mmol/L at the end of the bolus, remaining elevated (2.44 +/- 0.17 mmol/L) for 8 hours. Fetal magnesium concentrations (0.89 +/- 0.03 mmol/L before the bolus) did not change with the maternal infusion. In ewes not in labor, uterine contractures occurred 3.7 +/- 0.7 times per 2 hours before and did not change significantly with the infusion of magnesium sulfate. During corticotropin-induced preterm labor uterine contractions were present 13 +/- 3.2 times per hour before infusions and were unchanged by infusion of magnesium sulfate to the ewes. CONCLUSIONS: Magnesium sulfate infusion in pregnant sheep has no effect on either nonlabor uterine contractures or on corticotropin-induced preterm uterine contractions.
H A Akoury; S E White; J H Homan; V Y Cheung; B S Richardson; A D Bocking
Related Documents :
12797055 - Fetal aortic diameter pulse wave response to changes in maternal position after membran...
15019725 - Telemetric uterine contraction model in preterm cynomolgus monkeys.
9822525 - Fetal heart rate patterns in postasphyxiated fetal lambs with brain damage.
18316155 - A prospective randomized trial of acute tocolysis in term labour with atosiban or ritod...
732255 - Vasoactive peptides in experimental renal hypertension.
20306775 - Correlations between the blood pressure and other health variables in spanish adolescents.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  American journal of obstetrics and gynecology     Volume:  177     ISSN:  0002-9378     ISO Abbreviation:  Am. J. Obstet. Gynecol.     Publication Date:  1997 Jul 
Date Detail:
Created Date:  1997-08-19     Completed Date:  1997-08-19     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370476     Medline TA:  Am J Obstet Gynecol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  185-9     Citation Subset:  AIM; IM    
Department of Obstetrics and Gynaecology, University of Western Ontario, Lawson Research Institute, St. Joseph's Health Centre, London, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adrenocorticotropic Hormone / adverse effects
Blood Gas Analysis
Blood Pressure / drug effects,  physiology
Calcium / blood
Fetus / drug effects,  physiology
Heart Rate, Fetal / drug effects,  physiology
Hemoglobins / analysis
Infusions, Intravenous
Magnesium / blood
Magnesium Sulfate / administration & dosage,  pharmacology*
Neurotransmitter Agents / adverse effects
Obstetric Labor, Premature / chemically induced
Oxygen / blood
Pregnancy, Animal / blood,  physiology*
Respiration / drug effects,  physiology
Serum Albumin / analysis
Tocolytic Agents / administration & dosage,  pharmacology*
Uterine Contraction / drug effects*,  physiology
Uterus / drug effects,  physiology
Reg. No./Substance:
0/Hemoglobins; 0/Neurotransmitter Agents; 0/Serum Albumin; 0/Tocolytic Agents; 7439-95-4/Magnesium; 7440-70-2/Calcium; 7487-88-9/Magnesium Sulfate; 7782-44-7/Oxygen; 9002-60-2/Adrenocorticotropic Hormone

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Changes in activity of cytosolic phospholipase A2 in human amnion at parturition.
Next Document:  A randomized controlled trial of strict glycemic control and tertiary level obstetric care versus ro...