Effect of L-arginine therapy on the glomerular injury of preeclampsia: a randomized controlled trial.
OBJECTIVE
To assess the benefit of l-arginine, the precursor to nitric oxide, on blood pressure and recovery of the glomerular lesion in preeclampsia.


METHODS
Forty-five women with preeclampsia were randomized to receive either l-arginine or placebo until day 10 postpartum. Primary outcome measures including mean arterial pressure, glomerular filtration rate, and proteinuria were assessed on the third and 10th days postpartum by inulin clearance and albumin-to-creatinine ratio. Nitric oxide, cyclic guanosine 3'5' monophosphate, endothelin-1, and asymmetric-dimethyl-arginine and arginine levels were assayed before delivery and on the third and 10th days postpartum. Healthy gravid women provided control values. Assuming a standard deviation of 10 mm Hg, the study was powered to detect a 10-mm Hg difference in mean arterial pressure (alpha .05, beta .20) between the study groups.


RESULTS
No significant differences existed between the groups with preeclampsia before randomization. Compared with the gravid control group, women with preeclampsia exhibited significantly increased serum levels of endothelin-1, cyclic guanosine 3'5' monophosphate, and asymmetric-dimethyl-arginine before delivery. Despite a significant increase in postpartum serum arginine levels due to treatment, no differences were found in the corresponding levels of nitric oxide, endothelin-1, cyclic guanosine 3'5' monophosphate, or asymmetric-dimethyl-arginine between the two groups with preeclampsia. Further, there were no significant differences in any of the primary outcome measures with both groups demonstrating similar levels in glomerular filtration rate and equivalent improvements in both blood pressure and proteinuria.


CONCLUSIONS
Blood pressure and kidney function improve markedly in preeclampsia by the 10th day postpartum. Supplementation with l-arginine does not hasten this recovery.


METHODS
I.
Hladunewich
M A
MA
Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, California, USA. michelle.hladunewich@sw.ca
Derby
G C
GC
Lafayette
R A
RA
Blouch
K L
KL
Druzin
M L
ML
Myers
B D
BD
D000284:Administration, Oral; D000328:Adult; D001120:Arginine / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005865:Gestational Age; D005919:Glomerular Filtration Rate; D006801:Humans; D007231:Infant, Newborn; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology; D008423:Maternal Age; D010298:Parity; D049590:Postpartum Period; D011225:Pre-Eclampsia / Q000175:diagnosis / Q000188:drug therapy*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012016:Reference Values; D018570:Risk Assessment; D012720:Severity of Illness Index; D016896:Treatment Outcome
D001120:Arginine