Basal endothelial nitric oxide release is preserved in overweight and obese adults.
OBJECTIVE
Impaired basal nitric oxide release is associated with a number of cardiovascular disorders including hypertension, arterial spasm, and myocardial infarction. We determined whether basal endothelial nitric oxide release is reduced in otherwise healthy overweight and obese adult humans.


METHODS
Seventy sedentary adults were studied: 32 normal weight (BMI <25 kg/m(2)), 24 overweight (BMI > or = 25 < 30 kg/m(2)), and 14 obese (BMI > or = 30 kg/m(2)). Forearm blood flow (FBF) responses to intra-arterial infusions of N(g)-monomethyl-L-arginine (5 mg/min), a nitric oxide synthase inhibitor, were used as an index of basal nitric oxide release.


RESULTS
N(g)-monomethyl-L-arginine elicited significant reductions in FBF in the normal weight (from 4.1 +/- 0.2 to 2.7 +/- 0.2 mL/100 mL tissue/min), overweight (4.1 +/- 0.1 to 2.8 +/- 0.2 mL/100 mL tissue/min), and obese (3.9 +/- 0.3 to 2.7 +/- 0.2 mL/100 mL tissue/min) subjects. Importantly, the magnitude of reduction in FBF (approximately 30%) was similar among the groups.


CONCLUSIONS
These results indicate that the capacity of the endothelium to release nitric oxide under basal conditions is not compromised in overweight and obese adults.
DeSouza
Christopher A
CA
Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA. desouzac@colorado.edu
Van Guilder
Gary P
GP
Greiner
Jared J
JJ
Smith
Derek T
DT
Hoetzer
Greta L
GL
Stauffer
Brian L
BL
D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000187:drug effects; D004730:Endothelium, Vascular / Q000378:metabolism; D005260:Female; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology; D050177:Overweight / Q000502:physiology*; D018384:Oxidative Stress; D019323:omega-N-Methylarginine / Q000008:administration & dosage
D018836:Inflammation Mediators; D019323:omega-N-Methylarginine; D009569:Nitric Oxide