Endothelial and inducible nitric oxide synthase expression in Venezuelan patients with pre-eclampsia

Preeclampsia (PE) is a disease that onsets in the second half of pregnancy. This condition is characterized by hypertension, proteinuria and, frequently, intrauterine growth restriction (IUGR). Nitric oxide (NO) regulates blood flow in the human placenta, it induces vasodilatation, inhibition of platelet aggregation and prevents adhesion of platelets to endothelial cells. In this work, nitrite levels were evaluated in the sera of peripheral blood of normal pregnant women (n = 46) and women with PE (n = 50); additionally, the expression of endothelial constitutive nitric oxide and inducible synthases (eNOS and iNOS, respectively) of placental tissues, were determined. An increased concentration of serum nitrites from patients with PE, in relation to normal pregnant women (150.64 +/- 8.94 vs 40.62 +/- 1.65 microM, p < 0.00001) was observed. An increased expression of nitric oxide synthases (eNOS and iNOS), in the placental tissues of (PE) patients, as compared to that of normal pregnant women (iNOS 4.29 +/- 1.51 vs 0.59 +/- 0.13; eNOS 1.78 +/- 0.74 vs 0.46 +/- 0.22, p < 0.005) was also observed. Our results show that there exists a relationship between serum nitrites concentration and the expression of eNOS and iNOS, as analyzed in protein extracts of placental tissues.