Doppler analysis and placental nitric oxide synthase expression during fetal growth restriction.
OBJECTIVE
To assess placental nitric oxide (NO) metabolism related to changes in the uteroplacental circulation during fetal growth restriction (FGR).


METHODS
The resistance index (RI) from the uterine arteries and pulsatility index (PI) from the umbilical artery were determined by Doppler analysis in 15 patients with FGR and 12 healthy controls, before elective cesarean section. Inducible (iNOS) and endothelial (eNOS) NO synthase expression were measured in placental samples. Immunohistochemistry was performed for iNOS location in the placenta.


RESULTS
During FGR, we observed a significant elevation of iNOS when compared with controls. Conversely, eNOS did not differ between the two groups. A negative correlation with eNOS (r = -0.85) and a positive correlation with iNOS (r = 0.91) was found correlating to umbilical PI. The iNOS proteins were reduced in syncytiotrophoblast cells and increased in endothelium in the FGR group compared to the controls.


CONCLUSIONS
During FGR, placental iNOS expression is significantly increased; this increase possibly represents an adaptive physiological mechanism for overcoming a fetoplacental circulation deficiency.
Giannubilo
Stefano R
SR
Department of Obstetrics and Gynecology, Polytechnic University of Marche, Ancona, Italy. s.giannubilo@univpm.it
Menegazzi
Marta
M
Tedeschi
Elisa
E
Bezzeccheri
Valeria
V
Suzuki
Hisanori
H
Tranquilli
Andrea L
AL
D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005317:Fetal Growth Retardation / Q000378:metabolism*; D006801:Humans; D017078:Laser-Doppler Flowmetry; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism*; D010920:Placenta / Q000201:enzymology*; D021041:Placental Circulation; D011247:Pregnancy; D012039:Regional Blood Flow; D014599:Uterus / Q000098:blood supply
D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III