ABSENCE OF RELAXATION TO LACTATE IN HUMAN PLACENTAL VESSELS OF PREGNANCIES WITH SEVERE PREECLAMPSIA

Citation
Rf. Figuerosa et al., ABSENCE OF RELAXATION TO LACTATE IN HUMAN PLACENTAL VESSELS OF PREGNANCIES WITH SEVERE PREECLAMPSIA, American journal of obstetrics and gynecology, 173(6), 1995, pp. 1800-1806
Citations number
25
Categorie Soggetti
Obsetric & Gynecology
ISSN journal
00029378
Volume
173
Issue
6
Year of publication
1995
Pages
1800 - 1806
Database
ISI
SICI code
0002-9378(1995)173:6<1800:AORTLI>2.0.ZU;2-W
Abstract
OBJECTIVE: Our objective was to determine whether the observed relaxat ion to lactate and other agents in placental vessels of normal pregnan cies is altered in severe preeclampsia. STUDY DESIGN: Isolated placent al arteries and veins from women with severe preeclampsia and uncompli cated term pregnancies were precontracted with prostaglandin F-2 alpha under 5% oxygen and 5% carbon dioxide with the balance nitrogen (Po-2 35 to 38 torr) and then exposed to lactate (1 to 10 mmol/L, pH 7.4, n = 8 to 15), arachidonic acid (0.01 to 10 mu mol/L, n = 6 to 13), nitr oglycerin (1 nmol to 1 mu mol/L, n = 4 to 12), or forskolin (0.01 to 1 0 mu mol/L, n = 6 to 9). The response to lactate was also examined in placental vessels from appropriate-for-gestational-age preterm deliver ies (n = 8) for comparison with a similar group with severe preeclamps ia (n = 8). The t test and analysis of variance statistics were used. RESULTS: Relaxation to lactate was markedly inhibited in both placenta l arteries and veins of women with severe preeclampsia compared with v essels from uncomplicated term or preterm pregnancies. Responses to th e other relaxing agents were not altered in the severely preeclamptic vessels. CONCLUSIONS: In severe preeclampsia absence of lactate-induce d dilatation of placental vessels may contribute to the fetal complica tions associated with impaired blood flow and vasospasm.