Effects of ouabain on the isolated human uteroplacental vasculature

TY - JOUR

T1 - Effects of ouabain on the isolated human uteroplacental vasculature

AU - Glavind-Kristensen, M.

AU - Petersen, O. B.

AU - Forman, A.

PY - 1998

Y1 - 1998

N2 - OBJECTIVE: We sought to describe the effects of ouabain on the human uteroplacental vasculature. STUDY DESIGN: Stem villous vessels and intramyometrial arteries isolated from placental and myometrial biopsy specimens at term were mounted in organ baths. Moreover, isolated human placental cotyledons were perfused. RESULTS: Contractions induced by the thromboxane A2 analog U46619 were unaffected by pretreatment with ouabain 10-10 to 10-6 mol/L. In fetal vessels nitric oxide (10-8 to 3 x 10- 5 mol/L) induced relaxation of vascular tonus induced by U46619 and potassium. This relaxation was inhibited by pretreatment with ouabain 10-7 to 10-6 mol/L. These associations were unaffected by removal of the endothelium. In maternal arteries ouabain (10-6 mol/L) failed to significantly affect nitric oxide-induced relaxation. Ouabain (10-9 mol/L) significantly affected pressure-flow relationships in perfused cotyledons. CONCLUSIONS: Ouabain impairs nitric oxide-induced relaxation of human stem villous arteries and veins, which may explain the changes induced by therapeutically relevant concentrations of the drug on pressure-flow relationships in the perfused cotyledon. Thus treatment with cardiac glycosides in pregnancy may impair uteroplacental blood flow.

AB - OBJECTIVE: We sought to describe the effects of ouabain on the human uteroplacental vasculature. STUDY DESIGN: Stem villous vessels and intramyometrial arteries isolated from placental and myometrial biopsy specimens at term were mounted in organ baths. Moreover, isolated human placental cotyledons were perfused. RESULTS: Contractions induced by the thromboxane A2 analog U46619 were unaffected by pretreatment with ouabain 10-10 to 10-6 mol/L. In fetal vessels nitric oxide (10-8 to 3 x 10- 5 mol/L) induced relaxation of vascular tonus induced by U46619 and potassium. This relaxation was inhibited by pretreatment with ouabain 10-7 to 10-6 mol/L. These associations were unaffected by removal of the endothelium. In maternal arteries ouabain (10-6 mol/L) failed to significantly affect nitric oxide-induced relaxation. Ouabain (10-9 mol/L) significantly affected pressure-flow relationships in perfused cotyledons. CONCLUSIONS: Ouabain impairs nitric oxide-induced relaxation of human stem villous arteries and veins, which may explain the changes induced by therapeutically relevant concentrations of the drug on pressure-flow relationships in the perfused cotyledon. Thus treatment with cardiac glycosides in pregnancy may impair uteroplacental blood flow.

KW - Human intramyometrial arteries

KW - Human stem villous vessels

KW - Nitric oxide

KW - Ouabain

KW - Perfused placental cotyledon

U2 - 10.1016/S0002-9378(98)70520-4

DO - 10.1016/S0002-9378(98)70520-4

M3 - Journal article

C2 - 9609556

AN - SCOPUS:0031861671

SN - 0002-9378

VL - 178

SP - 892

EP - 898

JO - American Journal of Obstetrics and Gynecology

JF - American Journal of Obstetrics and Gynecology

IS - 5

ER -