Journal article
Agonist-specific impairment of coronary vascular function in genetically altered, hyperlipidemic mice
American journal of physiology. Regulatory, integrative and comparative physiology, Vol.276(4), pp.R1023-R1029
04/01/1999
DOI: 10.1152/ajpregu.1999.276.4.R1023
PMID: 10198381
Abstract
The objectives of the present study were to 1) examine mechanisms involved in endothelium-dependent responses of coronary arteries from normal mice and 2) determine whether vascular responses of coronary arteries are altered in two genetic models of hypercholesterolemia [apolipoprotein E (apoE)-deficient mice (apoE −/−) and combined apoE and low-density lipoprotein receptor (LDLR)-deficient mice (apoE + LDLR −/−)]. Plasma cholesterol levels were higher in both apoE −/− and apoE + LDLR −/− compared with normal mice on normal and high-cholesterol diets (normal chow: normal 110 ± 5 mg/dl, apoE −/− 680 ± 40 mg/dl, apoE + LDLR −/− 810 ± 40 mg/dl; high-cholesterol chow: normal 280 ± 60 mg/dl, apoE −/− 2,490 ± 310 mg/dl, apoE + LDLR −/− 3,660 ± 290 mg/dl). Coronary arteries from normal (C57BL/6J), apoE −/−, and apoE + LDLR −/− mice were isolated and cannulated, and diameters were measured using videomicroscopy. In normal mice, vasodilation in response to ACh and serotonin was markedly reduced by 10 μM N ω-nitro-l-arginine (an inhibitor of nitric oxide synthase) or 20 μM 1 H-[1,2,4]oxadiazolo[4,3- a]quinoxalin-1-one (ODQ; an inhibitor of soluble guanylate cyclase). Vasodilation to nitroprusside, but not papaverine, was also inhibited by ODQ. Dilation of arteries from apoE −/− and apoE + LDLR −/− mice on normal diet in response to ACh was similar to that observed in normal mice. In contrast, dilation of arteries in response to serotonin from apoE −/− and apoE + LDLR −/− mice was impaired compared with normal. In arteries from both apoE −/− and apoE + LDLR −/− mice on high-cholesterol diet, dilation to ACh was decreased. In apoE + LDLR −/− mice on high-cholesterol diet, dilation of coronary arteries to nitroprusside was increased. These findings suggest that dilation of coronary arteries from normal mice in response to ACh and serotonin is dependent on production of nitric oxide and activation of soluble guanylate cyclase. Hypercholesterolemia selectively impairs dilator responses of mouse coronary arteries to serotonin. In the absence of both apoE and the LDL receptor, high levels of cholesterol result in a greater impairment in coronary endothelial function.
Details
- Title: Subtitle
- Agonist-specific impairment of coronary vascular function in genetically altered, hyperlipidemic mice
- Creators
- Kathryn G Lamping - Department of Internal Medicine, The Cardiovascular Center, and Department of Veterans Affairs Medical Center, Iowa City, Iowa 52242Daniel W Nuno - Department of Internal Medicine, The Cardiovascular Center, and Department of Veterans Affairs Medical Center, Iowa City, Iowa 52242David A Chappell - Department of Internal Medicine, The Cardiovascular Center, and Department of Veterans Affairs Medical Center, Iowa City, Iowa 52242Frank M Faraci - Department of Internal Medicine, The Cardiovascular Center, and Department of Veterans Affairs Medical Center, Iowa City, Iowa 52242
- Resource Type
- Journal article
- Publication Details
- American journal of physiology. Regulatory, integrative and comparative physiology, Vol.276(4), pp.R1023-R1029
- DOI
- 10.1152/ajpregu.1999.276.4.R1023
- PMID
- 10198381
- ISSN
- 0363-6119
- eISSN
- 1522-1490
- Language
- English
- Date published
- 04/01/1999
- Academic Unit
- Cardiovascular Medicine; Neuroscience and Pharmacology; Internal Medicine
- Record Identifier
- 9984040365602771
Metrics
19 Record Views