Fetoplacental vascular tone during fetal circuit acidosis and acidosis with hypoxia in the ex vivo perfused human placental cotyledon
Objectives: Our purpose was to determine the effects of acidosis and acidosis-hypoxia on fetoplacental perfusion pressure and its response to angiotensin II. Study Design: Perfused cotyledons from 14 placentas were studied with either an acidotic fetal circuit perfusate ( n = 7) or an acidotic-hypox...
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Published in | American journal of obstetrics and gynecology Vol. 177; no. 5; pp. 1088 - 1092 |
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Main Authors | , , , , |
Format | Journal Article Conference Proceeding |
Language | English |
Published |
Philadelphia, PA
Mosby, Inc
01.11.1997
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | Objectives: Our purpose was to determine the effects of acidosis and acidosis-hypoxia on fetoplacental perfusion pressure and its response to angiotensin II.
Study Design: Perfused cotyledons from 14 placentas were studied with either an acidotic fetal circuit perfusate (
n = 7) or an acidotic-hypoxic fetal circuit perfusate (
n = 7). Each cotyledon's fetal vasculature was initially perfused under standard conditions and bolus injected with 1 × 10
–10 moles of angiotensin II. Fetoplacental perfusate was then replaced with either an acidotic medium (pH 6.90 to 7.00 and Po
2 516 to 613 mm Hg) or an acidotic-hypoxic medium (pH 6.90 to 7.00 and Po
2 20 to 25 mm Hg) followed by an angiotensin II injection. The vasculature was subsequently recovered with standard perfusate and again injected with angiotensin II. Perfusion pressures within each group were compared by one-way analysis of variance, and results were expressed as mean pressure ± SEM.
Results: Resting fetoplacental perfusion pressure did not change when the fetal circuit perfusate was made acidotic (28 ± 1 mm Hg vs 25 ± 2 mm Hg) or acidotic-hypoxic (26 ± 2 mm Hg vs 25 ± 2 mm Hg). The maximal fetoplacental perfusion pressure achieved in response to angiotensin II did not differ with an acidotic perfusate (41 ± 2 mm Hg vs 38 ± 1 mm Hg) or with an acidotic-hypoxic perfusate (39 ± 2 mm Hg vs 36 ± 2 mm Hg).
Conclusions: In the perfused placental cotyledon fetoplacental perfusion pressure and pressor response to angiotensin II are not affected by fetal circuit acidosis or acidosis-hypoxia. This suggests that neither fetal acidosis nor fetal acidosis combined with hypoxia has a direct effect on fetoplacental vascular tone. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0002-9378 1097-6868 |
DOI: | 10.1016/S0002-9378(97)70020-6 |