Endothelium-derived nitric oxide metabolites and soluble intercellular adhesion molecule-1 in diabetic and normal pregnancies.

Objective: Endothelial dysfunction has been demonstrated in adult subjects with diabetes. We studied if maternal diabetes is associated with altered endothelial function in the fetus, as this might shed light on mechanisms by which adult diseases are programmed in utero.

Study Design: Total nitrate/nitrite (NOx) concentration was measured spectrophotometrically with the Griess reagent method. Soluble intercellular adhesion molecule-1 (sICAM-1) concentration was measured by enzyme-linked immunoassay.

Results: Venous cord serum NOx concentration at birth was highest in pregnancies complicated by type 1 diabetes (29.5+/-1.8 micromol/l, n=63) (P<0.0001 versus controls) and lowest in normal pregnancies (19.0+/-1.0 micromol/l, n=56). The concentration was intermediate in pregnancies complicated by gestational diabetes (23.9+/-2.7 micromol/l, n=24), but not significantly higher than in normal pregnancies (P=0.172). Venous cord serum sICAM-1 concentration did not differ between the three groups (P=0.191). Maternal serum NOx concentration in the third trimester was higher in pregnancies complicated by type 1 diabetes (22.9+/-3.4 micromol/l, n=22) than in normal pregnancies (15.4+/-1.4 micromol/l, n=21) (P=0.049).

Conclusions: : Increased cord serum NOx but unaltered sICAM-1 concentration in diabetic pregnancies indicates that maternal diabetes does not cause a general alteration in fetal endothelial function. The increase in cord serum and maternal serum NOx concentration in diabetic pregnancies may be due to abnormalities in insulin-induced nitric oxide release or to a diminished reactivity of the vasculature to the effects of nitric oxide.