Altered sensitivity to a novel vasoconstrictor endothelin-1 (1-31) in myometrium and umbilical artery of women with severe preeclampsia

We have suggested that a novel endothelin-1 with 31 amino acids [ET-I (1-31 )] plays an important role in fetal circulation, owing to a strong contract ile activity on the umbilical artery. To clarify the pathophysiological sig nificance of ET-I (1-31) in the development of severe preeclampsia, its con tractile activities on human umbilical arteries and uterine smooth muscle f rom patients with preeclampsia were studied. The contraction by ET-I (1-31) was stronger in uterine smooth muscle of the patients with severe preeclam psia than that of normal subjects. On the contrary, the constrict-ion of um bilical artery of the patients with eclampsia was significantly weaker than that of normal pregnant women. The stronger contraction of myometrium by E T-I (1-31) in patients with severe preeclampsia observed for the first time in the present study suggests that ET-I (1-31) might be involved in the de velopment of preeclampsia. (C) 2001 Academic Press.