Oral arginine improves blood pressure in renal transplant and hemodialysis patients.
BACKGROUND
Hypertension in kidney transplant (KT) patients may result from attenuated whole-body nitric oxide (NO) content and abnormal NO-mediated vasodilation. Increasing NO bioavailability with L-arginine (ARG) could theoretically restore the NO-mediated vasodilatory response and lower blood pressure.


METHODS
In a prospective pilot study, 6 normotensive volunteers and 10 KT patients received oral supplements of ARG (9.0 g/d) for 9 days, then 18.0 g/d for 9 more days. Six hemodialysis (HD) and 4 peritoneal dialysis patients received the same dose for 14 days. Five KT patients received 30 mL/d of canola oil (CanO) in addition to ARG. Systolic (SBP) and diastolic (DBP) blood pressure, creatinine clearance (CCr), and serum creatinine (Cr) were measured at baseline, day 9, and day 18. In a subsequent study, 20 hypertensive KT patients with stable but abnormal renal function were randomized in a crossover study to start ARG-only or ARG+CanO supplements for two 2-month periods with an intervening month of no supplementation. SBP, DBP, CCr, and Cr were measured monthly for 7 months.


RESULTS
In the pilot study, ARG reduced the SBP in HD patients from 171.5 +/- 7.5 mmHg (baseline) to 142.8 +/- 8.3 mmHg (p = .028). In the crossover study, SBP was reduced from baseline (155.9 +/- 5.0 mmHg), after the first 2 months (143.2 +/- 3.2 mmHg; p = .03) and subsequent 2 months (143.3 +/- 2.5 mmHg; p = .014) of supplementation. DBP was also reduced after supplementation in both studies. CanO had no effect on blood pressure. Renal function did not change.


CONCLUSIONS
Oral preparations of ARG (+/-CanO) were well tolerated for up to 60 consecutive days and had favorable effects on SBP and DBP in hypertensive KT and HD patients.
Kelly
B S
BS
Department of Surgery, University of Cincinnati, Ohio 45267-0558, USA.
Alexander
J W
JW
Dreyer
D
D
Greenberg
N A
NA
Erickson
A
A
Whiting
J F
JF
Ogle
C K
CK
Babcock
G F
GF
First
M R
MR
D000328:Adult; D001120:Arginine / Q000008:administration & dosage* / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D003404:Creatinine / Q000097:blood / Q000652:urine; D018592:Cross-Over Studies; D019587:Dietary Supplements; D005229:Fatty Acids, Monounsaturated / Q000008:administration & dosage; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D007674:Kidney Diseases / Q000150:complications / Q000628:therapy*; D016030:Kidney Transplantation; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000378:metabolism; D010865:Pilot Projects; D011446:Prospective Studies; D000074262:Rapeseed Oil; D006435:Renal Dialysis; D014664:Vasodilation
D005229:Fatty Acids, Monounsaturated; D009566:Nitrates; D000074262:Rapeseed Oil; D009569:Nitric Oxide; D001120:Arginine; D003404:Creatinine