The relationship between serum nitrate and endothelin-1 concentrations in preeclampsia.
Recently it was suggested that abnormal endothelial function may contribute to the pathophysiological changes observed in preeclampsia (PE). Both nitric oxide (NO) and endothelin-1 (ET-1) are vasoactive substances produced by endothelial cells. NO is a vasodilator and has been believed to be decreased in PE. ET-1 is a vasoconstrictor and has been reported to be increased in PE. We simultaneously measured NO metabolites and ET-1 in sera from women with PE and investigated the correlation of NO and ET-1 concentrations. We obtained serum samples from 11 healthy nonpregnant (NP) women, 16 normotensive pregnant (NTP) women and 17 women with PE. In this study, the serum ET-1 level was assayed by the ET-1 RIA system, and serum NO metabolites were assayed by measuring nitrite (NO2-) and nitrate (NO3-) simultaneously in an HPLC-Griess reaction system. There was a significant correlation between NOx (nitrite + nitrate) and ET-1 in sera from all 44 women (NP, NTP and PE groups) (p<0.001). Nitrite and ET- in sera from each group were not significantly correlated. Nitrate and ET-1 in sera from the NP and NTP groups did not significantly correlate. However, there was a significant correlation between nitrate and ET-1 in sera from the PE group (p<0.05). The serum ET-1 and nitrate concentration in the PE group was significantly higher than in the NP and NTP groups (p<0.05 and p<0.001. respectively). These findings suggest that increased production of nitrate in PE may contribute to homeostatic vasodilation against vasoconstriction caused by a higher ET-1 concentration.
Nishikawa
S
S
Department of Obstetrics and Gynecology, Sapporo Medical University School of Medicine, Japan.
Miyamoto
A
A
Yamamoto
H
H
Ohshika
H
H
Kudo
R
R
D019332:Endothelin-1 / Q000097:blood*; D004730:Endothelium, Vascular / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D006801:Humans; D009566:Nitrates / Q000097:blood*; D011225:Pre-Eclampsia / Q000097:blood* / Q000503:physiopathology; D011247:Pregnancy
D019332:Endothelin-1; D009566:Nitrates