Contractile responses of the human umbilical artery from pregnancies complicated by intrauterine growth retardation.
The contractile properties of the umbilical artery to oxygen, U46619 (a stable thromboxane A2 mimetic) and 5-hydroxytryptamine (5-HT) were studied in normal term (> or = 37 weeks) and preterm (< 34 weeks) pregnancies, and in a group of pregnancies complicated by intrauterine growth retardation (IUGR). Isometric contractile responses in the preterm group to oxygen were reduced when compared with the term group, though no differences were found between these groups in the responses to either U46619 or 5-HT. In the IUGR group the responses to oxygen did not differ from gestationally matched normal pregnancies, though among those cases delivered preterm, the finding of absent end-diastolic flow velocity in the umbilical artery prior to delivery was associated with markedly diminished responses to oxygen. These data indicate the development of oxygen-induced contractions in the umbilical artery as pregnancy advances, which may fail to function in the severely growth-retarded fetus.
Templeton
A G
AG
Autonomic Physiology Unit, University of Glasgow, Scotland.
Kingdom
J C
JC
Whittle
M J
MJ
McGrath
J C
JC
D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D005260:Female; D005317:Fetal Growth Retardation / Q000503:physiopathology*; D006801:Humans; D066298:In Vitro Techniques; D007537:Isometric Contraction; D010100:Oxygen / Q000494:pharmacology; D011247:Pregnancy; D011248:Pregnancy Complications; D011450:Prostaglandin Endoperoxides, Synthetic / Q000494:pharmacology; D012701:Serotonin / Q000494:pharmacology; D013928:Thromboxane A2 / Q000031:analogs & derivatives / Q000494:pharmacology; D014469:Umbilical Arteries / Q000187:drug effects / Q000503:physiopathology*; D014661:Vasoconstriction; D014662:Vasoconstrictor Agents / Q000494:pharmacology
D011450:Prostaglandin Endoperoxides, Synthetic; D014662:Vasoconstrictor Agents; D012701:Serotonin; D013928:Thromboxane A2; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D010100:Oxygen