Increased L-citrulline/L-arginine plasma ratio in severe preeclampsia

Objective: To evaluate nitric oxide (NO) production in patients with pregna ncy-induced hypertension or preeclampsia and in controls. Methods: Four groups of pregnant women were included: 17 patients with preg nancy-induced hypertension, ten with mild or moderate preeclampsia, 17 with severe preeclampsia, and 44 normotensive women matched for weeks of gestat ion at blood sampling with the cases. Plasma levels of L-citrulline and L-a rginine were measured by using highperformance liquid chromatography. Results: The mean plasma levels of L-citrulline and the ratio of L-citrulli ne to L-arginine, which reflects NO production, were higher in women with s evere preeclampsia than in controls, patients with pregnancy-induced hypert ension, and patients with mild or moderate preeclampsia. Conclusion: Nitric oxide production is enhanced in severe preeclampsia, pos sibly as a compensatory phenomenon for the increased synthesis and release of vasoconstrictors and platelet-aggregating agents. (Obstet Gynecol 2000;9 6:395-9. (C) 2000 by The American College of Obstetricians and Gynecologist s).