| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Vascular Biology |
From the Division of Cardiology and Atherosclerosis Research Center, Burns and Allen Research Institute, and the Department of Medicine, Cedars-Sinai Medical Center and David Geffen School of Medicine at University of California, Los Angeles.
Correspondence to Paul C. Dimayuga, PhD, Davis Building, Room 1064, Cedars-Sinai Medical Center, 8700 Beverly Blvd, Los Angeles, CA 90048. E-mail dimayugap{at}cshs.org
Objective We investigated the role of inducible NO synthase (iNOS) in intimal thickening with exposure to cigarette smoke (CS).
Methods and Results Intimal thickening in wild-type (WT) and iNOS-deficient (iNOS/) mice subjected to CS exposure was induced by placement of a cuff around the carotid artery. CS exposure in WT mice was associated with increased arterial iNOS expression, superoxide production, activator protein-1 (AP-1) activation, and serum NO. Intimal thickening 21 days after cuff placement was significantly greater in mice exposed to CS compared with air (0.023±0.013 mm2 versus 0.009±0.008 mm2; P<0.05). iNOS inhibitor mercaptoethylguanidine-treated WT mice exposed to CS had reduced iNOS activity and intimal thickening (0.006±0.005 mm2; P<0.05). Intimal thickening was significantly less in iNOS/ mice compared with WT mice (0.006±0.005 mm2; P<0.01) and was not augmented with CS (0.002±0.002 mm2). The aryl hydrocarbon receptor (AhR) was detected in arteries in vivo and in smooth muscle cells (SMCs) in vitro. CS condensate treatment of SMCs increased AhR binding to the core xenobiotic-responsive element of the iNOS promoter and increased iNOS expression.
Conclusions Increased arterial expression of iNOS, mediated at least in part by AhR signaling, may be an important mechanism by which CS increases carotid intimal thickening. CS exposure in mice was associated with increased arterial iNOS expression, superoxide production, AP-1 activation, serum NO expression, and intimal thickening. Inhibition or deletion of iNOS abrogated the effects of CS.
We investigated the role of inducible nitric oxide synthase (iNOS) in intimal thickening with exposure to cigarette smoke (CS) exposure in WT mice was associated with increased arterial iNOS expression, superoxide production, AP-1 activation, serum NO, and intimal thickening. Inhibition or deletion of iNOS abrogated the effects of CS.
Key Words: smoking iNOS oxidative stress intimal thickening
This article has been cited by other articles:
![]() |
P. C. Dimayuga, H. Li, K.-Y. Chyu, G. N. Fredrikson, J. Nilsson, M. C. Fishbein, P. K. Shah, and B. Cercek T Cell Modulation of Intimal Thickening After Vascular Injury: The Bimodal Role of IFN-{gamma} in Immune Deficiency Arterioscler. Thromb. Vasc. Biol., December 1, 2005; 25(12): 2528 - 2534. [Abstract] [Full Text] [PDF] |
||||
|
ATVB Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2004 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |