Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004153 (atherosclerosis)
77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Nilvadipine (FK 235, FR 34235) suppressed ischemia (20 min)-reflow (20 min)-induced paw edema of mice (ED30:0.4 mg/kg i.v. and 2 mg/kg p.o.). Other calcium entry blockers of dihydropyridine-type also suppressed the edema, but 30-fold higher doses were required. 2. Oral dosing of nilvadipine suppressed carrageenan-induced paw edema (ED30:15 mg/kg in rats and 20 mg/kg in mice) at a potency corresponding to that of an anti-inflammatory drug, ibuprofen. Nifedipine, nicardipine and nimodipine resulted in a suppression of 30% only with 100 mg/kg oral dosing in rats. Nitrendipine, diltiazem and verapamil were without effect. 3. Nilvadipine inhibited superoxide radical (O-2production from xanthine oxidase (XOD) both with lactate dehydrogenase + NADH method and cytochrome c method (IC50:90 and 100 micrograms/ml, respectively). Nifedipine and nicardipine showed some inhibition, but the other calcium entry blockers failed to inhibit significantly even at 320 micrograms/ml. As uric acid formation was not reduced by the tested drugs, the inhibitory action might be due to their O-2scavenging effects. 4. Superoxide production of neutrophils from casein-induced peritoneal fluid in rats was most strongly inhibited by nilvadipine when the cells were stimulated by a calcium ionophore, A23187 (IC50:4 micrograms/ml). Inhibition by this drug when stimulated by f-methonyl-leucyl-phenylalanine and phorbol myristate acetate was less effective (IC50:20 and 30 micrograms/ml, respectively). Nifedipine and nicardipine inhibited neutrophil O-2production at higher concentrations (30-200 micrograms/ml) with all stimulants. Inhibitory actions by other drugs were weak. 5. Triggering of atherosclerosis depends largely on the oxidative stress on blood vessels after recently established concept.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Inhibition by nilvadipine of ischemic and carrageenan paw edema as well as of superoxide radical production from neutrophils and xanthine oxidase. 165 7

Activation of leukocytes in vivo produces marked constriction of large arteries in atherosclerotic, but not in normal, monkeys. We tested the hypotheses that vasoconstrictor responses to activated leukocytes in vivo may be abnormal during hypercholesterolemia before the development of atherosclerotic lesions and that responses may return to normal after the regression of atherosclerosis. Leukocytes were activated by injection of the chemotactic peptide formyl-methionine-leucine-phenylalanine (fMLP) into the blood-perfused hind limb of four groups of cynomolgus monkeys: monkeys fed a normal diet (normal group, n = 18), monkeys fed an atherogenic diet for 3-4 months (hypercholesterolemic group, n = 6), monkeys fed an atherogenic diet for 20 months (atherosclerotic group, n = 19), and monkeys fed an atherogenic diet for 18 months, followed by a normal diet for 20 months (regression group, n = 14). Baseline resistance of large arteries was 1.5 +/- 0.2 (mean +/- SEM), 2.0 +/- 0.6, 3.5 +/- 0.4 (p less than 0.05 versus normal), and 1.7 +/- 0.2 mm Hg/ml/min per 100 g tissue for the normal, hypercholesterolemic, atherosclerotic, and regression groups, respectively. Injection of fMLP did not change resistance of large arteries in normal or hypercholesterolemic monkeys. Injection of fMLP increased resistance of large arteries by 3.0 +/- 0.7 mm Hg/ml/min per 100 g tissue in atherosclerotic monkeys and by 1.3 +/- 0.4 mm Hg/ml/min per 100 g tissue in regression monkeys (p less than 0.05 versus atherosclerotic and normal). Thus, abnormal vasoconstriction in response to activation of leukocytes persists, but to a lesser extent, after regression. In contrast, vasoconstrictor responses to serotonin, which were potentiated in atherosclerotic monkeys, were normal after regression.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Vascular responses to activated leukocytes after regression of atherosclerosis. 173 39

Peripheral blood monocytes are involved during atherogenesis in adhering to endothelium, migrating into the subendothelial space and taking-up lipoproteins to become macrophage/foam cells. We have assessed whether peripheral blood monocyte characteristics are altered in human hyperlipidaemia in age/sex/smoking status matched pairs of patients and controls. Monocytes from the hypercholesterolaemic patients, as opposed to the controls, were more sensitive to stimulation by the agonist, N-formyl-methionyl-leucyl-phenylalanine, with respect to chemokinesis (stimulation index 1.48 +/- 0.17 vs. 1.10 +/- 0.14), chemotaxis (4.05 +/- 0.55 vs. 2.72 +/- 0.24) and adhesion to porcine aortic endothelial monolayers (1.26 +/- 0.05 vs. 1.17 +/- 0.06). The patients' monocyte total surface expression of the adhesion glycoprotein CD11b/CD18 (37.5 +/- 7.1 vs. 36.0 +/- 7.1), but not CD11c/CD18 (31.6 +/- 7.2 vs. 31.4 +/- 6.8), was increased; however, the monocytes in hyperlipidaemia were larger (9.15 +/- 0.11 microns vs. 8.98 +/- 0.11 microns) such that the surface density of CD11b/CD18 was not altered (0.144 +/- 0.029 vs. 0.142 +/- 0.029). The data suggest that circulating monocytes are functionally different in hypercholesterolaemia. This may explain the increased involvement by monocytes in hypercholesterolaemia-related atherogenesis.
Atherosclerosis 1991 Oct
PMID:Human monocyte characteristics are altered in hypercholesterolaemia. 175 87

The plasma concentration of lipoprotein (a) [Lp(a)] is correlated with the risk of atherosclerosis. It is a lipoprotein particle consisting of apoprotein (a) [Lp(a)] is correlated with the risk of atherosclerosis. It is a lipoprotein particle consisting of apoprotein (a) [apo(a)], a protein showing considerable amino acid sequence identity with plasminogen. bound to low-density lipoprotein. The apo(a) portion of Lp(a) was recently shown to have serine-proteinase-type amidolytic activity and to be able to degrade the adhesive glycoprotein fibronectin. To characterize this enzyme activity further, we used chromogenic peptide substrates and inhibitors. Of the substrates tested, those with arginine at the scissile bond [N-alpha-benzoyl-L-Arg p-nitroanilide (pNA), N-alpha-benzoyl-Ile-Glu-Gly-Arg-pNA, N-alpha-benzyloxycarbonyl-Arg-Gly-Arg-pNA] gave the highest hydrolysis rates. Synthetic substrates with plasmin specificity (Val-Leu-L-Lys-pNA and Val-Phe-L-Lys-pNA) were not hydrolysed by Lp(a). Neither tissue plasminogen activator nor urokinase had any effect on the enzyme activity. The addition of antibodies to these plasminogen activators did not inhibit the enzyme activity of Lp(a). Inhibition experiments with phenylmethanesulphonyl fluoride, carbodi-imide, dichloroisocoumarin and competitive peptide inhibitors demonstrated that Lp(a) has enzyme activity that closely resembles that of serine proteinases. Whether this serine-proteinase activity of Lp(a) plays any role in the genesis of atherosclerosis remains to be established.
...
PMID:Characterization of the enzyme activity of human plasma lipoprotein (a) using synthetic peptide substrates. 182 80

We aggregated human platelets in vitro and examined vascular responses to injection of the supernatant in atherosclerotic primates. Platelets were washed, suspended, and aggregated with thrombin. Thrombin was then inactivated with D-Phe-Pro-ArgCH2Cl, and the suspension was centrifuged. The supernatant was injected intra-arterially into the perfused hindlimb within 30 s after aggregation of platelets. We studied normal cynomolgus monkeys, atherosclerotic monkeys that were fed atherogenic diet for 18 mo, and regression monkeys that were fed an atherogenic diet for 18 mo followed by a normal diet for 20 mo. Products of activated human platelets produced vasodilation in normal monkeys, as effects of platelet-derived vasodilators (presumably adenine nucleotides) may override platelet vasoconstrictor products. Vasodilator responses to platelet products were impaired in atherosclerotic monkeys, probably as a result of endothelial dysfunction. Regression of atherosclerosis restored vasodilator responses to platelet products toward normal. These data suggest that the predominant response to human platelet products is vasodilatation. Atherosclerosis impairs vasodilator responses to human platelet products, and regression of atherosclerosis restores responses toward normal.
...
PMID:Effects of atherosclerosis and regression on vascular responses to products of activated platelets in primates. 201 10

The goal of this study was to test the hypothesis that atherosclerosis alters responses of cerebral arteries and the ocular circulation to the activation in vivo of leukocytes and platelets. We measured blood flow to the brain and eye using microspheres and pressure in the cerebral microvessels of normal and atherosclerotic monkeys. The intracarotid injection of 10(-7) M N-formyl-L-methionyl-L-leucyl-L-phenylalanine to activate leukocytes did not alter cerebral blood flow in 11 normal or 10 atherosclerotic monkeys but increased the resistance of large cerebral arteries by 46 +/- 11% (mean +/- SEM) in the atherosclerotic animals. The injection of N-formyl-L-methionyl-L-leucyl-L-phenylalanine did not alter blood flow to the eye in 10 normal monkeys but decreased blood flow to the choroid by 38 +/- 9% in 11 atherosclerotic monkeys. The intracarotid injection of 3 x 10(-9) M prostaglandin E2, a leukocyte product, produced an increase in the resistance of large cerebral arteries in five atherosclerotic but not in six normal monkeys. Prostaglandin E2 reduced blood flow to the retina and choroid in the atherosclerotic monkeys by 62 +/- 22% and 65 +/- 17%, respectively. The intracarotid infusion of 25 micrograms/min collagen to activate platelets increased cerebral blood flow by 21 +/- 5% in 10 normal monkeys but did not alter it in 11 atherosclerotic monkeys. Collagen did not alter blood flow to the choroid in 10 normal monkeys but decreased it by 29 +/- 8% in 11 atherosclerotic monkeys.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Effect of atherosclerosis on cerebral vascular responses to activation of leukocytes and platelets in monkeys. 205 80

Epidemiological evidence suggests a reduced rate of chronic inflammatory diseases and ischaemic heart disease in populations with a high consumption of fish. This has been ascribed to the high content in sea food of polyunsaturated fatty acids (PUFAs), belonging to the n - 3 family. We have studied neutrophil and monocyte chemotaxis in 12 healthy males before and after 6 weeks supplementation with cod liver oil, corresponding to 5.3 g n - 3 PUFAs daily. Neutrophil and monocyte chemotaxis were investigated using the under agarose technique with N-formyl-methionyl-leucyl-phenylalanine (N-FMLP) and autologous serum as chemoattractants. Neutrophil chemotaxis towards both chemoattractants and monocyte chemotaxis towards N-FMLP were significantly reduced after supplementation with cod liver oil.
Atherosclerosis 1989 May
PMID:Cod liver oil inhibits neutrophil and monocyte chemotaxis in healthy males. 271 62

Formula diets containing lard or lard and egg yolks were fed to six normolipidemic volunteers to investigate subsequent changes in the composition of lipoproteins of d less than 1.006 g/ml and in their ability to bind and be taken up by receptors on mouse macrophages. Both formulas induced the formation of d less than 1.006 lipoproteins that were approximately 3.5-fold more active than fasting very low density lipoproteins (VLDL) in binding to the receptor for beta-VLDL on macrophages. Subfractionation of postprandial d less than 1.006 lipoproteins by agarose chromatography yielded two subfractions, fraction I (chylomicron remnants) and fraction II (hepatic VLDL remnants), which bound to receptors on macrophages. However, fraction I lipoproteins induced a 4.6-fold greater increase in macrophage triglyceride content than fraction II lipoproteins or fasting VLDL. Fraction I lipoproteins were enriched in apolipoproteins (apo) B48, E, and [a]. Fraction II lipoproteins lacked apo[a] but possessed apo B100 and apo E. The apo[a] was absent in normal fasting VLDL, but was present in the d less than 1.006 lipoproteins (beta-VLDL) of fasting individuals with type III hyperlipoproteinemia. The apo[a] from postprandial d less than 1.006 lipoproteins was larger than either of two apo[a] subspecies obtained from lipoprotein (a) [Lp(a)] isolated at d = 1.05-1.09. However, all three apo[a] subspecies were immunochemically identical and had similar amino acid compositions: all were enriched in proline and contained relatively little lysine, phenylalanine, isoleucine, or leucine. The association of apo[a] with dietary fat-induced fraction I lipoproteins suggests that the previously observed correlation between plasma Lp(a) concentrations and premature atherosclerosis may be mediated, in part, by the effect of apo[a] on chylomicron remnant metabolism.
...
PMID:Fat feeding in humans induces lipoproteins of density less than 1.006 that are enriched in apolipoprotein [a] and that cause lipid accumulation in macrophages. 293 60

Optimization of a combination of balloon catheter-induced aortic de-endothelialization with provision of a palatable atherogenic diet to rabbits leads to hyperbetalipoproteinaemia and atherosclerosis rather than to the cholesterol-storage disease which characterized earlier models. Administration of BRL 26314 [N-(4-chlorobenzyl)-L-phenylalanine] during the induction of atherosclerosis specifically raised high-density lipoprotein (HDL) and decreased the arterial content of cholesterol and collagen in association with reduction in severity of thoracic sudanophilic lesions and intimal-thickening. This anti-atherosclerotic activity was superior to that observed for various standard compounds, and the present studies, using BRL 26314 as a pharmacological tool, provide evidence in vivo for an association between the elevation of HDL and reduction of arterial disease.
...
PMID:Hyperalphalipoproteinaemic activity of BRL 26314--II. Inhibition of atherosclerosis in rabbits. 654 92

We investigated the effects of mono-hydroxyeicosatetraenoic acids (HETEs) and N-formyl-methionyl-leucyl-phenylalanine (F-Met-Leu-Phe) on rat aortic smooth muscle cell migration in modified Boyden chambers. 12-HETE showed the most potent stimulatory effect on smooth muscle cell migration among the mono-HETEs tested. The optimal concentrations for cell migration were 3 X 10(-15) and 3 X 10(-13) g/ml for 12-HETE and 10(-8) g/ml for 15-HETE, 5-HETE and F-Met-Leu-Phe were inactive with these cells. As 12-HETE is biosynthesized from arachidonic acid by the 12-lipoxygenase pathway in platelets and macrophages, and 15-HETE by the 15-lipoxygenase pathway in granulocytes, the present results indicate an important role for such cells in the early phase of atherosclerosis.
Atherosclerosis 1982 Sep
PMID:Comparative effect of lipoxygenase products of arachidonic acid on rat aortic smooth muscle cell migration. 681 52


1 2 3 4 5 6 7 8 9 Next >>