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(Circulation. 1995;92:898-903.)
© 1995 American Heart Association, Inc.
Articles |
Dietary Correction of Hypercholesterolemia in the Rabbit Normalizes Endothelial Superoxide Anion Production
From the Divisions of Cardiology (Y.O., T.E.P., H.S.S., D.G.H.) and Hematology/Oncology (R.R.S., J.N.W.), Emory University School of Medicine, and the Atlanta Veterans Administration Medical Center (D.G.H.), Atlanta, Ga.
Correspondence to David G. Harrison, MD, Cardiology Division, PO Box Drawer LL, Emory University School of Medicine, Atlanta, GA 30322.
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Abstract |
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 Top Abstract IntroductionMethods Results Discussion References |
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Background We have shown that hypercholesterolemia increases vascular superoxide anion (O2-) production, which could be responsible for augmented inactivation of endothelium-derived vascular relaxing factor. We sought to determine whether this increased vascular O2- production is due to infiltration of macrophages into the intima and whether dietary treatment of hypercholesterolemia normalizes O2- production.
Methods and Results A specific and sensitive assay for O2- based on chemiluminescence of lucigenin was used; the amount of O2- produced by vascular ring segments was quantified based on known quantities of O2- produced by xanthine–xanthine oxidase standards. O2- production of aortic segments from normal rabbits (n=9), cholesterol-fed rabbits (1% cholesterol diet for 1 month, n=7), and rabbits fed a 1% cholesterol diet for 1 month followed by a normal diet for 1 month (regression rabbits, n=5) was measured. At the end of these diets, serum cholesterol levels were 1.5±0.2, 26.0±3.9, and 1.8±0.5 mmol/L (58±6, 1000±150, and 71±19 mg/dL) in the normal, cholesterol-fed, and regression animals, respectively. Vessels from normal rabbits with endothelium produced 0.32±0.06 nmol O2-/mg dry wt per minute, whereas those without endothelium produced approximately twice as much O2- (0.66±0.12 nmol O2- mg dry wt per minute. Vessels with endothelium from cholesterol-fed rabbits produced 4.5-fold more O2- than vessels from normal animals. This increased production of O2- was normalized by endothelial removal. This increased production of O2- was not due to infiltration of macrophages in the intima, because there was no correlation between vascular O2- production and macrophage infiltration assessed by immunohistochemistry with use of a specific antibody against rabbit macrophage. O2- production by vessels from regression rabbits was similar to that observed in normal animals, and as in the normal rabbits, endothelial removal increased O2- production. Aortic rings from these animals also were studied in organ chambers. Dietary lowering of cholesterol dramatically improved vasodilator responses to acetylcholine and A23187 (P<.05 versus cholesterol-fed rabbits).
Conclusions Dietary lowering of cholesterol not only improves endothelium-dependent vascular relaxation but also normalizes endothelial O2- production. Decreases of O2- production by dietary lowering of cholesterol not only may improve vasomotor control but also may improve other aspects of vascular integrity in atherosclerosis.
Key Words: hypercholesterolemia • macrophages • free radicals • endothelium-derived factors • vasodilation
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Introduction |
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TopAbstractIntroductionMethods Results Discussion References |
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The endothelium modulates vasomotor tone by release of an endothelium-derived relaxing factor now known to be nitric oxide1 or a closely related compound.2 This important function of the endothelium is impaired in the presence of several common diseases, including hypercholesterolemia and atherosclerosis.3 4 5 6 The mechanisms underlying this abnormality of vascular function have been the subject of substantial research and probably are multifactorial. One contributing factor may be excessive production of superoxide anion (O2-),7 8 which can inactivate nitric oxide.9 Treatment with polyethylene-glycol superoxide dismutase improves endothelium-dependent vascular relaxation in cholesterol-fed rabbits, providing indirect evidence for increased vascular O2- production in hypercholesterolemia.8 Recently, using lucigenin chemiluminescence, we have found that aortas from hypercholesterolemic rabbits produce substantially more O2- than control rabbit aortas.7 In these studies, endothelial removal normalized O2- production, indicating that the source of the O2- was not the smooth muscle layer but the endothelial cell itself or monocyte-macrophages closely associated with the endothelium. Oxypurinol also normalized O2- production in these vessels, suggesting a role of xanthine oxidase as a source of O2-.
There has been substantial interest in therapeutic means to correct alterations of endothelial function in hypercholesterolemia. In hypercholesterolemic animals, cholesterol lowering via either dietary or pharmacological means can improve endothelium-dependent vascular relaxations.10 11 Recent studies in human subjects have shown that large coronary artery responses to acetylcholine can be converted to a modest degree of vasodilatation by 6 months of aggressive lipid-lowering therapy.12
If alteration of endothelium-dependent vascular relaxation is in part due to excess production of O2-, then it would follow that improvement of hypercholesterolemia would not only improve relaxations to endothelium-dependent vasodilators but also lower O2- production. The present experiments were performed to test this hypothesis. A second aim of this study was to determine whether the increase in O2- production in cholesterol-fed rabbit aortas correlated with the degree of macrophage infiltration.
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Methods |
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TopAbstractIntroductionMethods Results Discussion References |
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Animal Model and Vessel Preparation
Three groups of New Zealand White rabbits were studied. The control group of animals (n=9) was fed standard rabbit chow. Plasma cholesterol level of control animals was 1.5±0.2 mmol/L (58±6 mg/dL). Age-matched rabbits (n=7) were fed a high cholesterol (1%) diet for 1 month. During this time, the plasma cholesterol increased to 26.0±3.9 mmol/L (1000±150 mg/dL) (P<.001 versus control). Other rabbits (regression, n=5) were fed a 1% cholesterol diet for 1 month and were then placed on a normal diet for the ensuing 1 month. Plasma cholesterol at the end of this time had decreased to 1.8±0.5 mmol/L (71±19 mg/dL) (P=NS versus control). On the day of study, the animals were killed by an overdose of intravenous sodium pentobarbital. The chest was then rapidly opened and the descending thoracic aorta removed. The vessel was placed in chilled Krebs-HEPES buffer, cleaned of excessive adventitial tissue, and cut into 5-mm ring segments. In some vessels, the endothelium was removed by inserting the closed tips of metal hemostat forceps into the ring segment and rolling it gently on moistened filter paper.
Measurements of Vascular Superoxide Anion
Production
O2- production was
measured using lucigenin chemiluminescence. The details of this assay
have been published previously.7 13 14
Briefly, after
preparation, the vessels were placed in a modified Krebs-HEPES buffer
(mmol/L content: NaCl, 99.01; KCl, 4.69; CaCl2,
1.87; MgSO4, 1.20;
K2HPO4, 1.03; NaHCO3,
25.0; Na-HEPES, 20.0; and glucose, 11.1; initially gassed with 95%
O2 and 5% CO2, pH 7.4) and allowed to
equilibrate for 30 minutes. Scintillation vials containing 2 mL of
Krebs-HEPES buffer with 0.25 mmol/L lucigenin were placed into a
scintillation counter switched to the out-of-coincidence mode. After 15
minutes, background counts were recorded, and a vascular segment
then was added to the vial. Scintillation counts then were recorded
15 minutes later and the respective background counts subtracted. The
vessels then were dried by placing them in a 90°C oven for 3 hours.
Lucigenin scintillation counts were converted to absolute amounts of
O2- with use of known quantities of
xanthine and xanthine oxidase as described
previously.7
Isometric Tension Studies
Ring segments from the same animals
also were studied in organ
chambers filled with Krebs-Henseleit buffer (mmol/L content: NaCl,
118.3; KCl, 4.69; CaCl2, 1.87;
MgSO4, 1.20; K2HPO4,
1.03; NaHCO3, 25.0; and glucose, 11.1; pH 7.40). The
buffer was aerated continuously with 95% O2 and 5%
CO2 and maintained at 37°C. Each segment was suspended by
means of metal stirrups, one of which was connected to a transducer to
allow measurement of isometric tension. During the following hour, the
vessels were gradually stretched to a resting tension of 5 g. In
preliminary experiments, we found that this was an optimum resting
tension for development of active contractile tone. After this, the
vessels were constricted with 1 µmol/L phenylephrine.
After development of a stable degree of active tension, the vessels
were exposed to cumulative concentrations of either acetylcholine (1
nmol/L to 3 µmol/L) or the calcium ionophore A23187 (1 nmol/L to 3
µmol/L).
Immunohistochemistry
Additional studies were performed to
attempt to determine the
role of macrophages in the increased
O2- production in
cholesterol-fed rabbit aortas. Sixteen segments from 8
hypercholesterolemic rabbits (plasma
cholesterol=29.6±5.5 mmol/L [1140±210 mg/dL])
and 4
segments from 2 regression rabbits (mean plasma
cholesterol=1.8 mmol/L [68 mg/dL]) were studied. After
measurement of O2- production,
the segments were weighed (wet weight). Preliminary experiments from 12
aortic segments revealed that the dry weight of the aorta was 22% of
the wet weight. We therefore used this value to estimate the dry weight
of these vessels. After weighing, the aortas were fixed in 4%
paraformaldehyde buffered with 0.1 mol/L
NaPO4 (pH 7.4) for 3 hours at 4°C, cryoprotected in 15%
sucrose PBS overnight, embedded in optimal cutting temperature compound
(OCT, Miles Laboratories), frozen in liquid nitrogen, and stored at
-70°C. Cryosections (7 µm) were thaw-mounted onto
Superfrost/Plus
slides (Fisher Scientific), refrozen, and stored at -70°C with
desiccant until use. Immunohistochemistry was performed using the
Vectastain ABC-AP system (Vector Laboratories) essentially as described
by the manufacturer. Cryosections were pretreated with acetone and 1%
gelatin-PBS and incubated at room temperature for 60 minutes with a
mouse anti-rabbit macrophage monoclonal antibody (RAM 11
[Reference 15], Dako Platts, 1:50) followed by incubation
with a
biotinylated horse anti-mouse secondary antibody (Vector Laboratories,
1:400) for 30 minutes. The tissue sections were subsequently stained
with use of Vector substrate kit I so that the final reaction
product appeared red. The slides were counterstained with
hematoxylin. The immunohistochemistry experiments were controlled by
incubating some sections with the secondary antibody only.
To relate
O2- production to the
extent of macrophage infiltration, we examined both
O2- production and
macrophage infiltration in individual vascular segments. An
additional 10 rabbits (8 hypercholesterolemic
rabbits and 2 regression rabbits) were used in these experiments. We
defined the extent of macrophage infiltration into four grades
(Fig 1
). Macrophage grading was performed by one
of the authors in a blinded fashion so that he was unaware of the
lucigenin signal obtained from the vascular segments studied. Eight
sections of the vascular segment in which
O2- production had been
determined were examined. A score was assigned to each vascular segment
based on analysis of all sections from that segment, and the
score assigned represented the highest number of
macrophages observed: grade 0, no macrophages observed;
grade 1, 1 to 3 macrophages in the histological
section; grade 2, the infiltration of macrophage occupied less
than one fourth of the circumferential area of lumen; grade 3, the
infiltration of macrophage occupied one fourth to one half of
the circumferential area of lumen; and grade 4, the infiltration of
macrophage occupied more than one half of the circumferential
area of lumen.
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All reagents were purchased from Sigma Chemical Co except when specified.
Statistics
Data are presented as mean±SEM. Differences
in
O2- production and vascular
relaxation were compared using ANOVA, and when differences between
groups were indicated, a Scheffé's post hoc analysis was
used. Probability values <.05 were considered significant.
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Results |
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TopAbstractIntroductionMethods Results Discussion References |
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Superoxide Anion Production
In aortic segments from normal rabbits (n=9), O2- production estimated by measuring chemiluminescence 15 minutes after exposure to lucigenin was 0.32 nmol/mg tissue per minute and was increased about twofold by removal of the endothelium (P<.05) (Fig 2
).
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P<.05, greater than with
endothelium.
In aortic segments from hypercholesterolemic
rabbits (n=7) with endothelium,
O2- production was 4.5 times
greater than that observed in normal aortas (P<.01) (Fig
2
). Furthermore, in contrast to the findings in normal aortas,
removal
of the endothelium from these
hypercholesterolemic aortas did not increase but
dramatically decreased O2-
production (P<.05) (Fig 2).
O2- production of segments of
hypercholesterolemic vessels without
endothelium was similar to normal segments without
endothelium.
In the regression group (n=5),
O2-
production was identical to values observed in normal rabbits
(Fig 2). Furthermore, as observed in normal vessels,
O2- production was increased
significantly by removal of the endothelium (Fig 2).
Thus, the endothelium in rabbits fed initially a high
cholesterol and then a normal diet also appears to exert a protective
role in limiting the total production of
O2- from the vessel wall.
Endothelium-Dependent Vascular
Relaxations
The degree of preconstriction by phenylephrine
averaged 8.0±0.7 g, 8.6±0.6 g, and 8.4±0.4 g
(P=NS) in
normal, cholesterol-fed, and regression rabbits,
respectively. Relaxations of vessels from the cholesterol-fed group to
acetylcholine and the calcium ionophore A23187 were markedly reduced
compared with control animals. After dietary lowering of
cholesterol, responses to these agonists were markedly
improved but were not as great as those observed in normal animals (Fig
3).
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Relation of Superoxide Anion Production to
Macrophage Infiltration in the Intima
As can be seen in Fig
4, there was no correlation
between vascular O2- production
and macrophage infiltration into the intima. Furthermore, in
several vascular segments with very high
O2- production, no
macrophages were observed.
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Discussion |
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TopAbstractIntroductionMethods Results Discussion References |
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In the present experiments, diet-induced hypercholesterolemia was associated with a 4.5-fold increase in the vascular production of O2-. As in a previous study,7 endothelial removal normalized O2- production, suggesting that the source of the O2- was the endothelium or cells closely associated with the endothelium. The new findings are that this increased O2- production probably is not due to infiltration of macrophages into the intima and that with dietary correction and lowering cholesterol, the vascular production of O2- was normalized. In addition to correction of O2- production, endothelium-dependent vascular relaxations to acetylcholine and the calcium ionophore A23187 were greatly improved.
Lucigenin chemiluminescence, used in the present experiments, has proven to be useful for studies of vascular O2- production.7 13 14 As previously noted, this methodology is quite specific for O2- production. Chemiluminescence is not produced by H2O2 in concentrations lower than 1 mmol/L (approximately 1 million times higher than O2-). The technique does not detect hydroxyl radical, singlet oxygen, or nitroxyl anion in concentrations less than 1 µmol/L.7 14 Luminol has been used previously to measure O2-; however, it also may detect other radicals such as hydroxyl and nitric oxide.16 The reduction of ferricytochrome c has been used to detect O2-,17 but we have found it less sensitive than lucigenin. Unlike ferricytochrome c, lucigenin also detects both intracellular and extracellular O2-13 18 and thereby provides a more accurate estimate of total vascular production and release of the radical.
The finding that cholesterol lowering was associated with an improvement in endothelium-dependent vascular relaxation is in keeping with prior reports in monkeys,10 rabbits,11 and more recently in humans.12 As the O2- production was also decreased, the findings are also compatible with the hypothesis that excess O2- may contribute to alterations of endothelium-dependent vascular relaxation. O2- inactivates nitric oxide, leading to the formation of nitrate and nitrite, which are vasoinactive except in very high concentrations. Because the O2- in hypercholesterolemia appears to be released by the endothelium, it is reasonable to assume that the inactivation of nitric oxide also may occur within the endothelium or shortly after the nitric oxide has been released from the endothelium. The chemical reaction betwen O2- and nitric oxide also may lead to the production of the peroxynitrite radical,19 20 which is vasoactive21 but has an extremely short biological half-life, which reduces its capacity to diffuse to the adjacent vascular smooth muscle.
In the present studies, as in previous work,7 we found
that removal of the endothelium from
cholesterol-fed rabbits decreased
O2- production. This finding
suggests that the source of the O2- is
either the endothelium or a cell type closely
associated with the endothelium that is also removed in
the denudation process. This consideration led us to examine the degree
of macrophage infiltration in a separate set of vessels from
cholesterol-fed rabbits and rabbits after dietary lowering
of cholesterol. We also were able to obtain estimates of
O2- production from the same
vascular segments so that a correlation between
O2- production and
macrophage infiltration could be obtained. As is evident from
Fig 4, there was no obvious relation between vascular
O2- production and the number
of macrophages present. In a large number of these
segments, no macrophages were observed. It is quite likely that
this absence of macrophages was due to the short-term
cholesterol feeding period and that had a longer feeding
period been used, macrophages would have been more
consistently observed. Nevertheless, these findings are
compatible with the concept that the endothelium can
serve as a source of O2-
production.
In the present studies, cholesterol lowering markedly improved but did not completely correct endothelium-dependent vascular relaxation. In two previous studies in which we sought to lower O2- production, an almost identical effect was observed. Treatment of cholesterol-fed rabbits with polyethylene-glycolated superoxide dismutase8 and prevention of O2- production by oxypurinol7 improved endothelium-dependent vascular relaxation to about 75% or 80% of that observed in control animals. In the present experiments and in the studies with oxypurinol, direct evidence was obtained that the interventions completely normalized O2- production. It is therefore interesting to speculate that a portion (approximately 75% to 80%) of the defect in endothelium-dependent vascular relaxation is due to O2- inactivation of nitric oxide and that other mechanisms may account for the remainder of the defect.
The present studies have focused on control of vasomotor tone; however, reducing vascular O2- production by cholesterol lowering may have other therapeutic implications. The O2- participates in oxidation and modification of low-density lipoprotein.22 Other radicals derived from O2- and peroxynitrite such as the hydroxyl radical and hydrogen peroxide may modify membrane lipids via formation of peroxy radicals23 and are chemoattractant for neutrophils.24 Recently, it has become clear that cellular redox state plays an important role in modulation of gene transcription25 26 27 28 and that at least one endothelial cell adhesion molecule (VCAM-1) involved in the atherogenic process may be transcriptionally regulated by oxidant stress.29 Oxygen radicals also may induce vascular smooth muscle growth and proliferation,30 an important component of atherogenesis. Thus, reduction of O2- production by cholesterol lowering not only may improve endothelial regulation of vasomotion but probably has several other beneficial effects with regard to vascular homeostasis.
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Acknowledgments |
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This work was supported by National Institutes of Health grants HL-32717, HL-39006, and HL-48667 and a Merit Grant from the Veterans Administration. We acknowledge the assistance of Ann B. Peterson and Cynthia M. Curry in the preparation of the manuscript.
Received December 13, 1994; revision received February 1, 1995; accepted February 10, 1995.
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References |
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|
TopAbstractIntroductionMethods Results Discussion References |
|---|
1. Palmer RMJ, Ferrige AG, Moncada S. Nitric oxide release accounts for the biological activity of endothelium-derived relaxing factor. Nature (Lond). 1987;327:524-526. [Medline] [Order article via Infotrieve]
2. Myers PR, Minor RL Jr, Guerra R, Bates JN, Harrison DG. Vasorelaxant properties of the endothelium-derived relaxing factor more closely resemble S-nitrosocysteine than nitric oxide. Nature (Lond). 1990;345:161-163. [Medline] [Order article via Infotrieve]
3. Jayakody RL, Senaratne MP, Thomson ABR, Kappagoda CT. Cholesterol feeding impairs endothelium-dependent relaxation of rabbit aorta. Can J Physiol Pharmacol. 1985;63:1206-1209. [Medline] [Order article via Infotrieve]
4.
Freiman PC, Mitchell GC, Heistad DD, Armstrong ML,
Harrison DG. Atherosclerosis impairs
endothelium-dependent vascular relaxation to
acetylcholine and thrombin in primates. Circ
Res. 1986;58:783-789.
5.
Habib JB, Bossaller C, Wells S, Williams C, Morrisett
JD, Henry PD. Preservation of
endothelium-dependent vascular relaxation in
cholesterol-fed rabbit by treatment with the calcium
blocker PN 200110. Circ Res. 1986;58:305-309.
6.
Verbeuren TJ, Jordaens FH, Zonnekeyn LL, Van Hove CE,
Coene MC, Herman AG. Effect of
hypercholesterolemia on vascular reactivity in
the rabbit. Circ Res. 1986;58:552-564.
7. Ohara Y, Peterson TE, Harrison DG. Hypercholesterolemia increases endothelial superoxide anion production. J Clin Invest. 1993;91:2546-2551.
8.
Mügge A, Elwell JH, Peterson TE, Hofmeyer TG,
Heistad DD, Harrison DG. Chronic treatment with polyethylene
glycolated superoxide dismutase partially restores
endothelium-dependent vascular relaxations in
cholesterol-fed rabbits. Circ
Res. 1991;69:1293-1300.
9. Rubanyi GM, Vanhoutte PM. Oxygen-derived free radicals, endothelium and responsiveness of vascular smooth muscle. Am J Physiol. 1986;250:H815-H821.
10. Harrison DG, Armstrong ML, Freiman PC, Heistad DD. Restoration of endothelium-dependent relaxation by dietary treatment of atherosclerosis. J Clin Invest. 1987;80:1808-1811.
11. Osborne JA, Lento PH, Siegfried MR, Stahl GL, Fusman B, Lefer AM. Cardiovascular effects of acute hypercholesterolemia in rabbits. J Clin Invest. 1989;83:465-473.
12. Leung WH, Pak LC, Wong CK. Beneficial effect of cholesterol-lowering therapy on coronary endothelium-dependent relaxation in hypercholesterolemic patients. Lancet. 1993;341:1496-1500. [Medline] [Order article via Infotrieve]
13. Cherry PD, Omar HA, Farrell KA, Stuart JS, Wolin MS. Superoxide anion inhibits cGMP-associated bovine pulmonary arterial relaxation. Am J Physiol. 1990;259(Heart Circ Physiol 28):H1056-H1062.
14.
Omar HA, Cherry PD, Mortelliti MP, Burke-Wolin T, Wolin
MS. Inhibition of coronary artery superoxide dismutase
attenuates endothelium-dependent and -independent
nitrovasodilator relaxation. Circ Res. 1991;69:601-608.
15. Tsukada T, Rosenfeld M, Ross R, Gown AM. Immunocytochemical analysis of cellular components in atherosclerotic lesions: use of monoclonal antibodies with the Watanabe and fat-fed rabbit. Arteriosclerosis. 1986;6:601-613. [Abstract]
16. Gyllenhammar H. Lucigenin chemiluminescence in the assessment of neutrophil superoxide production. J Immunol Methods. 1987;97:209-213. [Medline] [Order article via Infotrieve]
17.
Fridovich I. Quantitative aspects of the
production of superoxide anion radical by milk xanthine
oxidase. J Biol Chem. 1970;245:4053-4057.
18. Melinn M, McLaughlin H. Nitroblue tetrazolium reduction in lymphocytes. J Leukoc Biol. 1987;41:325-329. [Abstract]
19.
Beckman JS, Beckman TW, Chen J, Marshall PA, Freeman
BA. Apparent hydroxyl radical production by
peroxynitrite: implications for endothelial injury from
nitric oxide and superoxide. Proc Natl Acad Sci
U S A. 1990;87:1620-1624.
20. Radl R, Beckman JW, Bush KM, Freeman BA. Peroxynitrite induced membrane lipid peroxidation: the cytotoxic potential of superoxide and nitric oxide. Arch Biochem Biophys. 1991;288:481-487.[Medline] [Order article via Infotrieve]
21.
Liu S, Beckman JS, Ku DD. Peroxynitrite, a
product of superoxide and nitric oxide, produces coronary
vasorelaxation in dogs. J Pharmacol Exp
Ther. 1994;268:1114-1121.
22. Steinbrecher UP. Role of superoxide anion in endothelial-cell modification of low-density lipoprotein. Biochim Biophys Acta. 1988;929:20-30.
23.
Fong KL, McCay PB, Poyer JL. Evidence that
peroxidation of lysosomal membranes is initiated by hydroxyl free
radicals produced during flavin enzyme activity. J
Biol Chem. 1973;248:7792-7797.
24. Zimmerman BJ, Grisham MB, Granger DN. Role of oxidants in ischemia/reperfusion induced granulocyte infiltration. Am J Physiol (Gastrointestinal). 1990;258:G185-G190.
25.
Abate C, Patel L, Rauscher FI, Curran T. Redox
regulation of fos and jun DNA-binding activity in
vitro. Science. 1990;249:1157-1161.
26. Crawford D, Zbinden I, Amsted P, Cerutti P. Oxidant stress in duces the proto-oncogenes c-fos and c-myc in mouse epidermal cells. Oncogene. 1988;3:27-32.
27.
Storz G, Tartaglia LA, Ames BN. Transcriptional
regulator of oxidative stress-inducible genes: direct activation by
oxidation. Science. 1990;248:189-194.
28. Schreck R, Rieber P, Baeuerle PA. Reactive oxygen intermediates as apparently widely used messengers in the activation of the NF-KB transcription factor and HIV-1. EMBO J. 1991;10:2247-2258. [Medline] [Order article via Infotrieve]
29. Marui N, Offermann MK, Swerlick R, Kunsch C, Rosen CA, Ahmad M, Alexander RW, Medford RM. Vascular cell adhesion molecule-1 (VCAM-1) gene transcription and expression are regulated through an antioxidant-sensitive mechanism in human vascular endothelial cells. J Clin Invest. 1993;92:1866-1874.
30.
Rao GN, Berk BC. Active oxygen species stimulate
vascular smooth muscle cell growth and proto-oncogene
expression. Circ Res. 1992;70:593-599.
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N. Kalinina, A. Agrotis, E. Tararak, Y. Antropova, P. Kanellakis, O. Ilyinskaya, M. T. Quinn, V. Smirnov, and A. Bobik Cytochrome b558-Dependent NAD(P)H Oxidase-Phox Units in Smooth Muscle and Macrophages of Atherosclerotic Lesions Arterioscler Thromb Vasc Biol, December 1, 2002; 22(12): 2037 - 2043. [Abstract] [Full Text] [PDF]
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M. Aikawa, S. Sugiyama, C. C. Hill, S. J. Voglic, E. Rabkin, Y. Fukumoto, F. J. Schoen, J. L. Witztum, and P. Libby Lipid Lowering Reduces Oxidative Stress and Endothelial Cell Activation in Rabbit Atheroma Circulation, September 10, 2002; 106(11): 1390 - 1396. [Abstract] [Full Text] [PDF]
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 W. Palinski and S. Tsimikas Immunomodulatory Effects of Statins: Mechanisms and Potential Impact on Arteriosclerosis J. Am. Soc. Nephrol., June 1, 2002; 13(6): 1673 - 1681. [Abstract] [Full Text] [PDF]
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R. W. van Etten, E. J.P. de Koning, M. L. Honing, E. S. Stroes, C. A. Gaillard, and T. J. Rabelink Intensive Lipid Lowering by Statin Therapy Does Not Improve Vasoreactivity in Patients With Type 2 Diabetes Arterioscler Thromb Vasc Biol, May 1, 2002; 22(5): 799 - 804. [Abstract] [Full Text] [PDF]
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C. A. Hathaway, D. D. Heistad, D. J. Piegors, and F. J. Miller Jr Regression of Atherosclerosis in Monkeys Reduces Vascular Superoxide Levels Circ. Res., February 22, 2002; 90(3): 277 - 283. [Abstract] [Full Text] [PDF]
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 Y. K. Kim, M.-S. Lee, S. M. Son, I. J. Kim, W. S. Lee, B. Y. Rhim, K. W. Hong, and C. D. Kim Vascular NADH Oxidase Is Involved in Impaired Endothelium-Dependent Vasodilation in OLETF Rats, a Model of Type 2 Diabetes Diabetes, February 1, 2002; 51(2): 522 - 527. [Abstract] [Full Text] [PDF]
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Y.-M. Go, A.-L. Levonen, D. Moellering, A. Ramachandran, R. P. Patel, H. Jo, and V. M. Darley-Usmar Endothelial NOS-dependent activation of c-Jun NH2- terminal kinase by oxidized low-density lipoprotein Am J Physiol Heart Circ Physiol, December 1, 2001; 281(6): H2705 - H2713. [Abstract] [Full Text] [PDF]
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U. Landmesser and D. G. Harrison Oxidant Stress as a Marker for Cardiovascular Events: Ox Marks the Spot Circulation, November 27, 2001; 104(22): 2638 - 2640. [Full Text] [PDF]
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R. A. Beswick, A. M. Dorrance, R. Leite, and R. C. Webb NADH/NADPH Oxidase and Enhanced Superoxide Production in the Mineralocorticoid Hypertensive Rat Hypertension, November 1, 2001; 38(5): 1107 - 1111. [Abstract] [Full Text] [PDF]
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N. K. Thakur, T. Hayashi, D. Sumi, H. Kano, T. Tsunekawa, and A. Iguchi HMG-CoA reductase inhibitor stabilizes rabbit atheroma by increasing basal NO and decreasing superoxide Am J Physiol Heart Circ Physiol, July 1, 2001; 281(1): H75 - H83. [Abstract] [Full Text] [PDF]
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J. Martinez-Gonzalez, B. Raposo, C. Rodriguez, and L. Badimon 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase Inhibition Prevents Endothelial NO Synthase Downregulation by Atherogenic Levels of Native LDLs : Balance Between Transcriptional and Posttranscriptional Regulation Arterioscler Thromb Vasc Biol, May 1, 2001; 21(5): 804 - 809. [Abstract] [Full Text] [PDF]
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V. J. Dzau Tissue Angiotensin and Pathobiology of Vascular Disease : A Unifying Hypothesis Hypertension, April 1, 2001; 37(4): 1047 - 1052. [Abstract] [Full Text] [PDF]
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A. D. Dobrian, M. J. Davies, S. D. Schriver, T. J. Lauterio, and R. L. Prewitt Oxidative Stress in a Rat Model of Obesity-Induced Hypertension Hypertension, February 1, 2001; 37(2): 554 - 560. [Abstract] [Full Text] [PDF]
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M. Rodriguez-Porcel, J. D. Krier, A. Lerman, P. F. Sheedy II, J. C. Romero, C. Napoli, and L. O. Lerman Combination of Hypercholesterolemia and Hypertension Augments Renal Function Abnormalities Hypertension, February 1, 2001; 37(2): 774 - 780. [Abstract] [Full Text] [PDF]
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R. A. Beswick, H. Zhang, D. Marable, J. D. Catravas, W. D. Hill, and R. C. Webb Long-Term Antioxidant Administration Attenuates Mineralocorticoid Hypertension and Renal Inflammatory Response Hypertension, February 1, 2001; 37(2): 781 - 786. [Abstract] [Full Text] [PDF]
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 V. Schachinger, M.B. Britten, S. Dimmeler, and A.M. Zeiher NADH/NADPH oxidase p22 phox gene polymorphism is associated with improved coronary endothelial vasodilator function Eur. Heart J., January 1, 2001; 22(1): 96 - 101. [Abstract] [PDF]
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D Tousoulis, C Tentolouris, T Crake, G Goumas, C Stefanadis, P Toutouzas, and G Davies Complex stenosis morphology and vasomotor responses to inhibition of nitric oxide synthesis Heart, November 1, 2000; 84(5): 529 - 534. [Abstract] [Full Text]
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 S. H. Hohnloser Prevention of recurrent life-threatening arrhythmias: will lipid-lowering therapy make a difference? J. Am. Coll. Cardiol., September 1, 2000; 36(3): 773 - 775. [Full Text] [PDF]
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K. M. Channon, H. Qian, and S. E. George Nitric Oxide Synthase in Atherosclerosis and Vascular Injury : Insights From Experimental Gene Therapy Arterioscler Thromb Vasc Biol, August 1, 2000; 20(8): 1873 - 1881. [Abstract] [Full Text] [PDF]
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P. A. Kaufmann, T. Gnecchi-Ruscone, K. P. Schafers, T. F. Luscher, and P. G. Camici Low density lipoprotein cholesterol and coronary microvascular dysfunction in hypercholesterolemia J. Am. Coll. Cardiol., July 1, 2000; 36(1): 103 - 109. [Abstract] [Full Text] [PDF]
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E. S. G. Stroes, E. E. van Faassen, M. Yo, P. Martasek, P. Boer, R. Govers, and T. J. Rabelink Folic Acid Reverts Dysfunction of Endothelial Nitric Oxide Synthase Circ. Res., June 9, 2000; 86(11): 1129 - 1134. [Abstract] [Full Text] [PDF]
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M. J. Somers, K. Mavromatis, Z. S. Galis, and D. G. Harrison Vascular Superoxide Production and Vasomotor Function in Hypertension Induced by Deoxycorticosterone Acetate-Salt Circulation, April 11, 2000; 101(14): 1722 - 1728. [Abstract] [Full Text] [PDF]
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T. Tanaka, M. Kurabayashi, Y. Aihara, Y. Ohyama, and R. Nagai Inducible Expression of Manganese Superoxide Dismutase by Phorbol 12-Myristate 13-Acetate Is Mediated by Sp1 in Endothelial Cells Arterioscler Thromb Vasc Biol, February 1, 2000; 20(2): 392 - 401. [Abstract] [Full Text] [PDF]
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T. W. Hein, J. C. Liao, and L. Kuo oxLDL specifically impairs endothelium-dependent, NO-mediated dilation of coronary arterioles Am J Physiol Heart Circ Physiol, January 1, 2000; 278(1): H175 - H183. [Abstract] [Full Text] [PDF]
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T. J. Anderson Assessment and treatment of endothelial dysfunction in humans J. Am. Coll. Cardiol., September 1, 1999; 34(3): 631 - 638. [Full Text] [PDF]
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J. Y. Jeremy, D. Rowe, A. M. Emsley, and A. C. Newby Nitric oxide and the proliferation of vascular smooth muscle cells Cardiovasc Res, August 15, 1999; 43(3): 580 - 594. [Full Text] [PDF]
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M. M. Tarpey, C. R. White, E. Suarez, G. Richardson, R. Radi, and B. A. Freeman Chemiluminescent Detection of Oxidants in Vascular Tissue : Lucigenin But Not Coelenterazine Enhances Superoxide Formation Circ. Res., May 28, 1999; 84(10): 1203 - 1211. [Abstract] [Full Text] [PDF]
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R. Wever, P. Boer, M. Hijmering, E. Stroes, M. Verhaar, J. Kastelein, K. Versluis, F. Lagerwerf, H. van Rijn, H. Koomans, et al. Nitric Oxide Production Is Reduced in Patients With Chronic Renal Failure Arterioscler Thromb Vasc Biol, May 1, 1999; 19(5): 1168 - 1172. [Abstract] [Full Text] [PDF]
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C. M. Schmalfuss, L. Y. Chen, J. N. Bott, E. D. Staples, and J. L. Mehta Superoxide Anion Generation, Superoxide Dismutase Activity, and Nitric Oxide Release in Human Internal Mammary Artery and Saphenous Vein Segments Journal of Cardiovascular Pharmacology and Therapeutics, January 1, 1999; 4(4): 249 - 257. [Abstract] [PDF]
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I. Kurose, R. E. Wolf, M. B. Grisham, and D. N. Granger Hypercholesterolemia Enhances Oxidant Production in Mesenteric Venules Exposed to Ischemia/Reperfusion Arterioscler Thromb Vasc Biol, October 1, 1998; 18(10): 1583 - 1588. [Abstract] [Full Text] [PDF]
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T. W. Hein and L. Kuo LDLs Impair Vasomotor Function of the Coronary Microcirculation : Role of Superoxide Anions Circ. Res., August 24, 1998; 83(4): 404 - 414. [Abstract] [Full Text] [PDF]
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E. Van Belle, C. Bauters, T. Asahara, and J. M. Isner Endothelial regrowth after arterial injury: from vascular repair to therapeutics Cardiovasc Res, April 1, 1998; 38(1): 54 - 68. [Full Text] [PDF]
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A. Nitenberg, F. Paycha, S. Ledoux, R. Sachs, J.-R. Attali, and P. Valensi Coronary Artery Responses to Physiological Stimuli Are Improved by Deferoxamine but not by L-Arginine in Non–Insulin-Dependent Diabetic Patients With Angiographically Normal Coronary Arteries and No Other Risk Factors Circulation, March 3, 1998; 97(8): 736 - 743. [Abstract] [Full Text] [PDF]
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M. de Lorgeril Dietary arginine and the prevention of cardiovascular diseases Cardiovasc Res, March 1, 1998; 37(3): 560 - 563. [Full Text] [PDF]
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J. S. Luoma, P. Stralin, S. L. Marklund, T. P. Hiltunen, T. Sarkioja, and S. Yla-Herttuala Expression of Extracellular SOD and iNOS in Macrophages and Smooth Muscle Cells in Human and Rabbit Atherosclerotic Lesions : Colocalization With Epitopes Characteristic of Oxidized LDL and Peroxynitrite-Modified Proteins Arterioscler Thromb Vasc Biol, February 1, 1998; 18(2): 157 - 167. [Abstract] [Full Text] [PDF]
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 F. M. FARACI and D. D. HEISTAD Regulation of the Cerebral Circulation: Role of Endothelium and Potassium Channels Physiol Rev, January 1, 1998; 78(1): 53 - 97. [Abstract] [Full Text] [PDF]
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S. Hoshida, N. Yamashita, J. Igarashi, K. Aoki, T. Kuzuya, and M. Hori Long-term Probucol Treatment Reverses the Severity of Myocardial Injury in Watanabe Heritable Hyperlipidemic Rabbits Arterioscler Thromb Vasc Biol, November 1, 1997; 17(11): 2801 - 2807. [Abstract] [Full Text]
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R. H. Boger, S. M. Bode-Boger, R. P. Brandes, L. Phivthong-ngam, M. Bohme, R. Nafe, A. Mugge, and J. C. Frolich Dietary L-Arginine Reduces the Progression of Atherosclerosis in Cholesterol-Fed Rabbits : Comparison With Lovastatin Circulation, August 19, 1997; 96(4): 1282 - 1290. [Abstract] [Full Text]
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C. Cardillo, C. M. Kilcoyne, R. O. Cannon III, A. A. Quyyumi, and J. A. Panza Xanthine Oxidase Inhibition With Oxypurinol Improves Endothelial Vasodilator Function in Hypercholesterolemic but Not in Hypertensive Patients Hypertension, July 1, 1997; 30(1): 57 - 63. [Abstract] [Full Text]
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H. H. Ting, F. K. Timimi, E. A. Haley, M.-A. Roddy, P. Ganz, and M. A. Creager Vitamin C Improves Endothelium-Dependent Vasodilation in Forearm Resistance Vessels of Humans With Hypercholesterolemia Circulation, June 17, 1997; 95(12): 2617 - 2622. [Abstract] [Full Text]
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W. Aji, S. Ravalli, M. Szabolcs, X.-c. Jiang, R. R. Sciacca, R. E. Michler, and P. J. Cannon L-Arginine Prevents Xanthoma Development and Inhibits Atherosclerosis in LDL Receptor Knockout Mice Circulation, January 21, 1997; 95(2): 430 - 437. [Abstract] [Full Text]
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O. Tamai, H. Matsuoka, H. Itabe, Y. Wada, K. Kohno, and T. Imaizumi Single LDL Apheresis Improves Endothelium-Dependent Vasodilatation in Hypercholesterolemic Humans Circulation, January 7, 1997; 95(1): 76 - 82. [Abstract] [Full Text]
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N. Inoue, S. Ramasamy, T. Fukai, R. M. Nerem, and D. G. Harrison Shear Stress Modulates Expression of Cu/Zn Superoxide Dismutase in Human Aortic Endothelial Cells Circ. Res., July 1, 1996; 79(1): 32 - 37. [Abstract] [Full Text]
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C. A. Hathaway, D. D. Heistad, D. J. Piegors, and F. J. Miller Jr Regression of Atherosclerosis in Monkeys Reduces Vascular Superoxide Levels Circ. Res., February 22, 2002; 90(3): 277 - 283. [Abstract] [Full Text] [PDF]
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