The comparative effects of big endothelin-1, endothelin-1, and endothelin-3 in the human fetal-placental circulation
This study compared the effects of big endothelin-1, endothelin-1, and endothelin-3 and whether endothelin-converting enzyme was present in the human fetal-placental circulation. Single cotyledons of term placentas were dually perfused in vitro, and increases in fetal-placental perfusion pressure to...
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Published in | American journal of obstetrics and gynecology Vol. 167; no. 6; p. 1651 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
United States
01.12.1992
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Subjects | |
Online Access | Get more information |
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Summary: | This study compared the effects of big endothelin-1, endothelin-1, and endothelin-3 and whether endothelin-converting enzyme was present in the human fetal-placental circulation.
Single cotyledons of term placentas were dually perfused in vitro, and increases in fetal-placental perfusion pressure to bolus injections of big endothelin-1, endothelin-1, and endothelin-3 (8 x 10(-10) to 1 x 10(-7) mol/L) were recorded. Responses to big endothelin-1 (10(-7) mol/L) were measured in the same placenta before and after perfusion of the fetal-placental circulation with the neutral metalloprotease inhibitor phosphoramidon (10(-5) mol/L), which acts as an endothelin-converting enzyme inhibitor. All experiments were performed in at least five separate placentas.
Significant concentration-dependent increases in fetal-placental perfusion pressure were seen with endothelin-1 (p < 0.0005), endothelin-3 (p < 0.0256), and big endothelin-1 (p < 0.0034, analysis of variance). Big endothelin-1 always elicited transient vasodilatation before constriction. Phosphoramidon significantly inhibited the vasoconstrictor effect of big endothelin-1 (p < 0.039, paired t test).
The three endothelins tested are vasoconstrictors, and endothelin-converting enzyme is present in the fetal-placental circulation. |
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ISSN: | 0002-9378 |
DOI: | 10.1016/0002-9378(92)91756-Z |