title: Renal functional reserve and nitric oxide in patients with compensated liver cirrhosis.
abstract: To investigate the role of nitric oxide (NO) with respect to kidney function and liver cirrhosis, we evaluated renal function, as well as cyclic guanosine monophosphate (cGMP) and NOx (nitrite/nitrate [NO3-/NO2-]) as indirect markers of NO formation in plasma and urine at rest and during amino acid (aa)-induced glomerular hyperfiltration in patients with Child A liver cirrhosis and portal hypertension (n = 12), and in healthy controls (n = 10). Baseline filtration rate (GFR) and effective renal plasma flow (ERPF) were significantly lower in patients with cirrhosis than in controls (GFR: mean 88 +/- SD 16 mL/min vs. 106 +/- 15 mL/min, P = .01, ERPF: 477 +/- 93 vs. 561 +/- 72 mL/min, P = .002). In both groups amino acid (aa) infusion increased GFR, ERPF, as well as cGMP and urinary NOx. Changes in GFR were similar in cirrhotic patients and controls (28.3% +/- 14% in cirrhotics and 26% +/- 11% in controls), but the degree of aa-induced changes in ERPF was more marked in patients with liver cirrhosis (31.8% +/- 17% vs. 18.6% +/- 12%, P = .02). Plasma levels of NOx and cGMP were similar in either group at baseline and during aa infusion, whereas NOx and cGMP excretion in cirrhotics was constantly 14% to 24% lower than in the control group. We conclude that patients with compensated liver cirrhosis and portal hypertension already have an impaired kidney function. In addition our data suggest a cirrhosis-related dissociation between ERPF and GFR during aa stimulation. Further studies are warranted to find out whether a local imbalance between vasoconstrictors and vasodilators, e.g., decreased local NO formation, plays a key role for this phenomenon.
authors.affiliation: Department of General Internal Medicine, University of Bonn, Germany.
authors.forename: R P
authors.initials: RP
authors.lastname: Woitas
authors.forename: J
authors.initials: J
authors.lastname: Heller
authors.forename: B
authors.initials: B
authors.lastname: Stoffel-Wagner
authors.forename: U
authors.initials: U
authors.lastname: Spengler
authors.forename: T
authors.initials: T
authors.lastname: Sauerbruch
mesh_terms: D000328:Adult; D000368:Aged; D000450:Aldosterone / Q000097:blood; D001794:Blood Pressure; D005260:Female; D005919:Glomerular Filtration Rate; D006339:Heart Rate; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D008103:Liver Cirrhosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000502:physiology*; D012079:Renal Circulation; D012083:Renin / Q000097:blood
chemical_list: D009569:Nitric Oxide; D000450:Aldosterone; D012083:Renin