Plasma nitric oxide, endothelin-1 and urinary nitric oxide and cyclic guanosine monophosphate levels in hypertensive pregnant women

Objective: To compare serum levels of nitric oxide (NO) and endothelin-1 (ET-1), and urinary concentrations of NO and cyclic guanosine monophosphate (cGMP) between preeclamptic and normotensive pregnant women. Method: Ninety-one preeclamptic (48 mild, 43 severe) and forty healthy normotensive pregnant women above 32 gestational weeks were recruited into study. Chemiluminesence technique was used for measuring plasma and urinary NO levels, and radioimmunoassay was used to determine plasma ET-1 and urinary cGMP levels. Result: Plasma and urinary NO, and urinary cGMP levels were significantly lower in preeclamptics than in the control group (respectively, p < 0.001, p < 0.001, p < 0.01). Plasma ET-1 levels were significantly higher in the preeclamptics than in the control group (p < 0.001). There were significant negative correlations between plasma ET-1, plasma NO and urinary NO and cGMP in all groups. There were positive correlations between plasma NO, urinary NO and cGMP in all groups. Conclusion: The imbalance between NO and ET-1 may play a significant role in the pathophysiology of preeclampsia.