HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 292/5/H2093    most recent 01202.2006v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Focardi, M. Articles by Chilian, W. M. Search for Related Content PubMed PubMed Citation Articles by Focardi, M. Articles by Chilian, W. M.

Restoration of coronary endothelial function in obese Zucker rats by a low-carbohydrate diet

¹Department of Physiology and ³Departments of Surgery and Anesthesiology, Louisiana State University Health Sciences Center, New Orleans, Louisiana; and ²Department of Cardiology, University of Siena, Siena, Italy

Submitted 1 November 2006 ; accepted in final form 8 January 2007

A popular diet used for weight reduction is the low-carbohydrate diet, which has most calories derived from fat and protein, but effects of this dietary regimen on coronary vascular function have not been identified. We tested the hypothesis that obesity-induced impairment in coronary endothelial function is reversed by a low-carbohydrate diet. We used four groups of male Zucker rats: lean and obese on normal and low-carbohydrate diets. Rats were fed ad libitum for 3 wk; total caloric intake and weight gain were similar in both diets. To assess endothelial and vascular function, coronary arterioles were cannulated and pressurized for diameter measurements during administration of acetylcholine or sodium nitroprusside or during flow. When compared with lean rats, endothelium-dependent acetylcholine-induced vasodilation was impaired by 50% in obese rats (normal diet), but it was restored to normal by the low-carbohydrate diet. When the normal diet was fed, flow-induced dilation (FID) was impaired by >50% in obese compared with lean rats. Similar to acetylcholine, responses to FID were restored to normal by a low-carbohydrate diet. N-nitro-L-arginine methyl ester (10 µM), an inhibitor of nitric oxide (NO) synthase, inhibited acetylcholine- and flow-induced dilation in lean rats, but it had no effect on acetylcholine- or flow-induced vasodilation in obese rats on a low-carbohydrate diet. Tetraethylammonium, a nonspecific K⁺ channel antagonist, blocked flow-dependent dilation in the obese rats, suggesting that the improvement in function was mediated by a hyperpolarizing factor independent of NO. In conclusion, obesity-induced impairment in endothelium-dependent vasodilation of coronary arterioles can be dramatically improved with a low-carbohydrate diet most likely through the production of a hyperpolarizing factor independent of NO.

coronary circulation; endothelium; nitric oxide; Atkins diet

This article has been cited by other articles:

				J. Muller-Ehmsen, D. Braun, T. Schneider, R. Pfister, N. Worm, K. Wielckens, C. Scheid, P. Frommolt, and M. Flesch Decreased number of circulating progenitor cells in obesity: beneficial effects of weight reduction Eur. Heart J., June 2, 2008; 29(12): 1560 - 1568. [Abstract] [Full Text] [PDF]

				S. A. Phillips Effects of low-carbohydrate diet on vascular health: more than just weight loss Am J Physiol Heart Circ Physiol, May 1, 2007; 292(5): H2037 - H2039. [Full Text] [PDF]