title: Biochemical evidence for impaired nitric oxide synthesis in patients with peripheral arterial occlusive disease.
abstract: BACKGROUND
  We studied urinary nitrate and cGMP excretion rates, indices of systemic NO formation, and plasma concentrations of L-arginine and the endogenous NO synthase inhibitor asymmetrical dimethylarginine (ADMA) and its inactive stereoisomer, symmetrical dimethylarginine, in 77 patients with peripheral arterial occlusive disease (PAOD) in Fontaine stages IIb through IV and in 47 young and 37 elderly healthy control subjects.
  
  
  RESULTS
  Urinary nitrate excretion was 182.0+/-11.4 micromol/mmol creatinine and cGMP excretion was 186.2+/-13.0 nmol/mmol creatinine in young healthy control subjects. In elderly control subjects, both excretion rates were slightly lower (nitrate, 156.0+/-7.8 micromol/mmol creatinine; cGMP, 150.0+/-8.3 nmol/mmol creatinine; P=NS). In PAOD patients, there was a significant, progressive reduction of urinary nitrate (IIb, 138.4+/-11.9; III, 128.6+/-11.3; and IV, 91.9+/-8.0 micromol/mmol creatinine; P<.05) and cGMP (IIb, 139.9+/-25.2; III, 115.6+/-13.1; and IV, 76.9+/-7.9 nmol/mmol creatinine; P<.05) excretion rates related to the Fontaine stage of PAOD. These changes were independent of changes in renal excretory function. Plasma L-arginine concentrations were not significantly different between the groups, but ADMA concentrations were elevated in PAOD patients (young control subjects, 1.25+/-0.11; elderly control subjects, 1.01+/-0.05 micromol/L; IIb, 2.62+/-0.24; III, 3.06+/-0.48; and IV, 3.49+/-0.26 micromol/L; P<.05 for PAOD versus control subjects). There was a significant linear correlation between urinary nitrate and cGMP excretion rates and a significant negative linear correlation between plasma ADMA concentrations and urinary nitrate excretion.
  
  
  CONCLUSIONS
  In PAOD patients, there is a progressive reduction in urinary nitrate and cGMP excretion rates, which may be caused in part by accumulation of ADMA, an endogenous inhibitor of NO synthase.
authors.affiliation: Institute of Clinical Pharmacology, Medical School, Hannover, Germany.
authors.forename: R H
authors.initials: RH
authors.lastname: Böger
authors.forename: S M
authors.initials: SM
authors.lastname: Bode-Böger
authors.forename: W
authors.initials: W
authors.lastname: Thiele
authors.forename: W
authors.initials: W
authors.lastname: Junker
authors.forename: K
authors.initials: K
authors.lastname: Alexander
authors.forename: J C
authors.initials: JC
authors.lastname: Frölich
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism; D001120:Arginine / Q000031:analogs & derivatives / Q000097:blood / Q000494:pharmacology; D001157:Arterial Occlusive Diseases / Q000378:metabolism*; D006152:Cyclic GMP / Q000652:urine; D018450:Disease Progression; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000652:urine; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016491:Peripheral Vascular Diseases / Q000378:metabolism*; D014664:Vasodilation / Q000502:physiology
chemical_list: D004791:Enzyme Inhibitors; D009566:Nitrates; D009569:Nitric Oxide; C018524:N,N-dimethylarginine; D001120:Arginine; D019001:Nitric Oxide Synthase; D006152:Cyclic GMP