| Myoendometrial versus placental uterine arteries: structural, mechanical, and functional differences in late-pregnant rabbits. | |
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MedLine Citation:
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PMID: 9240609 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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OBJECTIVE: This study compared late-pregnant radial uterine arteries that supplied the placenta versus the myoendometrium to evaluate differences in active and passive mechanical properties. STUDY DESIGN: Pressurized segments of placental versus myoendometrial radial uterine arteries from late-pregnant (day 28 to 30) New Zealand White rabbits (n = 12) were compared in vitro for differences in luminal diameter, wall thickness, distensibility, and intrinsic tone as a function of transmural pressure. RESULTS: Both types of arteries responded to increased transmural pressure with active vasoconstriction; however, the amount of tone present in myoendometrial arteries was significantly greater than in placental arteries (percent tone at 75 mm Hg = 39% +/- 3% for myoendometrial versus 31% +/- 2% for placental arteries, p < 0.01). Measurements of unpressurized, fully relaxed arteries revealed that placental arteries were 38% larger in diameter and had thicker walls than myoendometrial arteries did. However, myoendometrial arteries were significantly more distensible at transmural pressures >5 mm Hg. CONCLUSIONS: The increased size and diminished tone of placental compared with adjacent myoendometrial arteries would favor increased blood flow to the placenta; differences in size and passive mechanical properties suggest that a localized factor(s) originating from the fetus or placenta contributes to the gestational enlargement of those arteries that perfuse the placenta. |
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Authors:
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M J Cipolla; N D Binder; G Osol |
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Publication Detail:
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Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: American journal of obstetrics and gynecology Volume: 177 ISSN: 0002-9378 ISO Abbreviation: Am. J. Obstet. Gynecol. Publication Date: 1997 Jul |
Date Detail:
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Created Date: 1997-08-19 Completed Date: 1997-08-19 Revised Date: 2007-11-14 |
Medline Journal Info:
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Nlm Unique ID: 0370476 Medline TA: Am J Obstet Gynecol Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: 215-21 Citation Subset: AIM; IM |
Affiliation:
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Department of Surgery, Oregon Health Sciences University, Portland 97201, USA. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Animals Arteries / anatomy & histology, physiology Female Models, Biological Myometrium / blood supply*, physiology Placenta / blood supply*, physiology Pregnancy Pregnancy, Animal / physiology* Rabbits Regional Blood Flow Uterus / blood supply*, physiology* Vascular Resistance / physiology Vasoconstriction / physiology |
| Grant Support | |
ID/Acronym/Agency:
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44941//PHS HHS |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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