Impact of NO-synthase inhibition on renal hemodynamics in normotensive and hypertensive subjects.
OBJECTIVE
To examine the acute effects of NO-synthase inhibition on renal hemodynamics in normotensive and hypertensive subjects.


METHODS
Changes of renal plasma flow (RPF) and glomerular filtration rate (GFR) in response to intravenous infusions of NG-monomethyl-l-arginine (l-NMMA) (3 mg/kg per 30 min) were measured in 32 normotensive and in 39 essential hypertensive patients by use of clearance technique.


RESULTS
l-NMMA significantly decreased RPF in normotensive and hypertensive individuals (P < 0.001), while GFR was preserved. Changes of renal hemodynamic parameters were similar in hypertensive and normotensive subjects (deltaRPF: -88 +/- 89 versus -81 +/- 105 ml/min, P = NS; deltaGFR 1.6 +/- 8.2 versus 4.3 +/- 8.9 ml/min, P = NS) Furthermore, l-NMMA increased mean arterial pressure (deltaMAP 5.3 +/- 6.3 versus 6.0 +/- 6.1 mmHg, P = NS) and decreased heart rate (deltaHR -5.8 +/- 3.9 versus -4.1 +/- 3.8 beats/min, P = NS) to a similar extent in both groups.


CONCLUSIONS
Basal NO synthesis of the renal vasculature is not impaired in patients with established essential hypertension.
Jacobi
Johannes
J
Department of Medicine/Nephrology, University of Erlangen-Nürnberg, Germany.
Schneider
Markus P
MP
John
Stefan
S
Schmieder
Roland E
RE
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D015331:Cohort Studies; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D012016:Reference Values; D012079:Renal Circulation / Q000187:drug effects*; D019323:omega-N-Methylarginine / Q000008:administration & dosage / Q000494:pharmacology*
D004791:Enzyme Inhibitors; D019323:omega-N-Methylarginine; D019001:Nitric Oxide Synthase