Nitric oxide modulation of renal and cardiac hemodynamics in type 2 diabetes.
OBJECTIVE
To evaluate endothelial function in type 2 diabetic patients with and without diabetic nephropathy.


METHODS
We studied the effects of systemic infusion of the nitric oxide (NO) synthase inhibitor NG-monomethyl-l-arginine (L-NMMA) on cardiovascular and renal hemodynamics in six type 2 diabetic patients with microalbuminuria (D2-MA), six type 2 diabetic patients with normoalbuminuria (D2-NA) and five control subjects. Both type 2 diabetic patients and control subjects had mild arterial hypertension.


RESULTS
L-NMMA infusion decreased the cardiac index in all groups. A reduction in glomerular filtration rate (GFR) and an increase in filtration fraction were observed only in controls. Renal plasma flow decreased in controls and D2-NA patients and renal vascular resistance increased in all groups.


CONCLUSIONS
The effect of L-NMMA on cardiac output was similar in controls and type 2 diabetic patients with and without diabetic nephropathy. In contrast, the effect on GFR was impaired in both diabetic groups, suggesting that glomerular NO homeostasis is altered in type 2 diabetes. Moreover the discrepancy, in diabetic patients, between cardiac and renal effects during L-NMMA infusion suggests that the modulation of glomerular hemodynamics is independent from NO-regulated cardiac output.
Dalla Vestra
Michele
M
Department of Medical and Surgical Sciences, Clinica Medica I, University of Padova, Via Giustiniani 2, 35128, Italy. michele.dallavestra@unipd.it
Sacerdoti
David
D
Bombonato
Giancarlo
G
Fioretto
Paola
P
Finucci
Gianfranco
G
Saller
Alois
A
Sfriso
Andrea
A
Bruseghin
Marino
M
Sambataro
Maria
M
Velussi
Mario
M
Baggio
Bruno
B
Nosadini
Romano
R
Crepaldi
Gaetano
G
D000328:Adult; D000419:Albuminuria / Q000209:etiology; D002302:Cardiac Output / Q000187:drug effects; D003326:Coronary Circulation / Q000502:physiology*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology* / Q000652:urine; D003928:Diabetic Nephropathies / Q000503:physiopathology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006439:Hemodynamics; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000502:physiology*; D012016:Reference Values; D012079:Renal Circulation / Q000502:physiology*; D019323:omega-N-Methylarginine / Q000494:pharmacology
D004791:Enzyme Inhibitors; D019323:omega-N-Methylarginine; D009569:Nitric Oxide