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)

Hypercholesterolaemia is thought to foster atherosclerosis and impotence through its effects on vascular endothelium. In this study, we investigated the pharmacological changes in rabbit corpus cavernosum (CC) secondary to incubation with lysolecithin and hypercholesterolaemia. A daily egg yolk dietary supplement induced gross hypercholesterolaemia in our rabbits. Group A of test animals (n-12) was fed with the yolk content of single egg and group B (n-6), that from two eggs for eight weeks. Serum level estimation revealed a progressive elevation of cholesterol to 15 and 30 times respectively, in the two treated groups as compared to values in the control group (n-6). Early histological manifestations of atherosclerosis were perceived as fat cell lesions in the cavernosum of treated animals. In vitro pharmacological studies on CC strips from both groups of test animals demonstrated a profound accentuation of the contractile responses to noradrenaline and histamine and attenuation of relaxant response to acetylcholine. However, in contrast to single-egg treated group, which demonstrated a reduction in the relaxant response to electrical field stimulation (EFS), there was a marked and statistically significant potentiation of this nitrergic transmission, in the two-eggs group. Prior incubation of CC strips of normolipidaemic rabbits (n-7) with lysolecithin, reproduced similar exaggerated response to EFS. Therefore, from the results of our study, it is concluded that oxidised LDL or its major amphiphile lysolecithin, at some critical level or beyond, may be capable of reverting at least some of the adverse effects of hypercholesterolaemia on erectile function, through its mediating effect on nitrergic transmission.
...
PMID:Elevated low-density lipoprotein cholesterol (LDL-C) enhances pro-erectile neurotransmission in the corpus cavernosum. 1040 85

We have studied the relationship between free and sulfoconjugated catecholamines (CAs) in the plasma of patients with various cardiovascular diseases and have described the physiological significance of sulfoconjugated CAs in plasma. In the present study, we measured free and sulfoconjugated dopamine (DA) and noradrenaline (NA) in the plasma of patients with atherosclerosis (AS). Results showed that the plasma levels of free DA and NA in patients with atherosclerosis were higher than those in control subjects. Moreover, it was also observed that the plasma levels of conjugated DA and NA in patients had a tendency to be higher than the levels in control subjects. These results suggest the involvement of free CAs in atherosclerosis and that elevated free CAs may be converted to sulfoconjugated forms in patients with atherosclerosis.
...
PMID:Plasma levels of free and sulfoconjugated catecholamines in patients with atherosclerosis. 1040 44

The effects were determined in rats of single injections of reserpine at increasing doses (0.5, 1.58, and 5.0 mg/kg) on low-density lipoprotein (LDL) and cholesterol in aortic wall, heart, liver, kidney, and adrenal gland. Catecholamine levels in plasma, heart, and liver, arterial blood pressure, and heart rate were also monitored. Reserpine was injected intraperitoneally, followed immediately by the administration of [3H]cholesterol by gavage. Twelve hours later, homologous 125I-tyramine cellobiose-labeled LDL (125I-TC-LDL) was injected intravenously. Twenty-four hours later, the rats were killed, and the radioactivities of aortic walls, heart, liver, kidney, and adrenal glands were determined. The results showed that after reserpine treatment the accumulation of both the 125I-TC label derived from LDL and total [3H]cholesterol was significantly reduced in aortic wall and heart, increased in liver, and unchanged in the kidney and adrenal gland. At higher doses (1.58 and 5.0 mg/kg), reserpine significantly accelerated the plasma clearance of radiolabelled LDL. Plasma noradrenaline in reserpine-treated animals decreased maximally (86%) by 12 h and by 61-71% at 36 h compared with the control. Plasma adrenaline increased transiently after injection of reserpine and then returned to the basal levels. Reserpine greatly decreased noradrenaline and adrenaline levels in heart and liver. Arterial blood pressure was decreased significantly (0.001 < p < 0.05) at 12 h by the two lower doses of reserpine and then returned to normal values over the next 24 h. The results indicate that reserpine decreases LDL cholesterol in artery wall and heart and increases it in liver. These findings suggest that reserpine could find a new use as a cholesterol-lowering drug for the prevention of atherosclerosis.
...
PMID:Effect of reserpine treatment on low-density lipoproteins in arterial wall and internal organs of rats. 1081 68

Viscum album L. has been used in the indigenous system of medicine for treatment of various diseases such as atherosclerosis and hypertension. In the literature, phenylpropan and flavonoid derivatives were suggested to play a role in the inhibition of cyclic adenosine monophosphate (cAMP)-phosphodiesterase (PDE) and a correlation was proposed between the in vitro inhibition of PDE and in vivo pharmacological activity. The vascular effects of the phenolic compounds and subfractions isolated from n-butanolic fraction of V. album ssp. album were studied on noradrenaline-contracted rat aortic rings. Isolated phenolic compounds (Syringin (VA-1), Coniferin (VA-9), 5, 7-dimethoxy-flavanone-4'-O-[beta-D-apiofuranosyl(1-->2)]-beta-D-gl uco pyranoside (VA-4)) produced concentration-dependent contractions in rat aortic rings. Only one compound (Kalopanaxin D (VA-15)) displayed very slight relaxant response. The weak concentration-dependent relaxing effect of the subfractions gave the idea that vasodilator activity were observed in the less polar subfractions. In addition, there was no clear correlation between the weak relaxant effects of subfractions and an inhibitory effect on cAMP-PDE.
...
PMID:Studies on the vascular effects of the fractions and phenolic compounds isolated from Viscum album ssp. album. 1096 90

Vatanidipine is a novel dihydropyridine (DHP)-type calcium channel blocker with slow-onset pharmacological actions, which are probably due to both its slow uptake into vascular tissues and resistance in its approach to the calcium channel binding site. Vatanidipine once incorporated into vascular tissues is not easily released, even by repeated washing, thus resulting in a long-lasting action of the agent. A slow-onset and long-lasting hypotensive action was observed in various experimental hypertensive models. Clinical trials using human subjects with essential hypertension indicated that vatanidipine exerts an antihypertensive effect with a slow onset and long duration. In spite of its potent hypotensive effect, the incidence of adverse effects by vatanidipine administration has been reported to be lower than that in cases of nitrendipine. In addition to its vasodilatory effects, vatanidipine efficiently suppressed noradrenaline release from sympathetic nerve endings, thus suggesting this agent exhibits a beneficial effect in the treatment of hypertensive patients, in which the reflex activation of peripheral sympathetic nerves is unfavourable to antihypertensive therapy. In a double-blind study, vatanidipine did not show reflex tachycardia, despite producing a potent and long-lasting hypotensive effect, in contrast to the administration of nitrendipine. In an animal study, vatanidipine exhibited a protective effect against cerebrovascular lesions, through a mechanism independent of its hypotensive effect. In addition, a renoprotective effect was also observed in experimental hypertensive models. In cholesterol-fed rabbits, vatanidipine exerted an anti-atherosclerotic action, which is probably attributable to the inhibitory action of the agent on low-density lipoprotein oxidation. In essential hypertensive patients, the plasma levels of cholesterol and triglyceride decreased after vatanidipine treatment, thus suggesting that this agent may have a therapeutic potential in preventing such vascular diseases as atherosclerosis. Taken together, vatanidipine appears to be a novel and useful antihypertensive agent, which can both prevent target-organ damage and reduce cardiovascular morbidity and mortality.
...
PMID:Vatanidipine hydrochloride: a new long-lasting antihypertensive agent. 1111 87

Garlic is known for its pharmacologic and nutritional properties. In previous studies, garlic elicited a reduction in plasma levels of lipids by inhibiting hepatic cholesterol synthesis. The aim of this study was to investigate in an in vivo model the effects of garlic extract and some fractions on cholesterol levels and vascular reactivity in cholesterol-fed rats. Rats were fed a cholesterol-enriched diet for 16 wk and were divided into 10 groups as follows: control and hypercholesterolemic diet groups, 4 groups fed frozen garlic fractions and 4 groups fed raw garlic fractions with different doses. Blood samples were obtained to analyze HDL and LDL cholesterol levels. After treatment, rats were killed. The heart, liver and kidneys were weighed; the aorta was isolated, mounted in organ chambers and vascular reactivity was tested. Plasma concentration of cholesterol was 58 mg/dL (100%) at the beginning of the study and increased to 102 mg/dL (153%; hypercholesterolemic group) at the end of the treatment. Plasma total cholesterol decreased in all groups treated with garlic; moreover, this effect was higher in rats fed raw garlic fractions and extracts. LDL decreased significantly with respect to the hypercholesterolemic group in all groups treated with garlic fractions and extracts (P: < 0.01); however, an increase in HDL was found in those treated with frozen fractions and extracts. The liver:body weight ratio decreased in all treated groups. The relaxing effect of acetylcholine (ACh) was enhanced in arteries contracted with noradrenaline (NE). These data suggest that garlic fractions could prevent diet-induced hypercholesterolemia and vascular alterations in the endothelium-dependent relaxation associated with atherosclerosis.
...
PMID:Study of garlic extracts and fractions on cholesterol plasma levels and vascular reactivity in cholesterol-fed rats. 1123 4

Regional sympathetic activity can be studied in humans using electrophysiological methods measuring sympathetic nerve firing rates and neurochemical techniques providing quantification of noradrenaline spillover to plasma from sympathetic nerves in individual organs. Essential hypertension: Such measurements in patients with essential hypertension disclose activation of the sympathetic outflows to skeletal muscle blood vessels, the heart and kidneys, particularly in younger patients. This sympathetic activation, in addition to underpinning the blood pressure elevation, most likely also contributes to left ventricular hypertrophy, and to the commonly associated metabolic abnormalities of insulin resistance and hyperlipidaemia. Antihypertensive drugs, such as moxonidine, which act primarily by inhibiting the sympathetic nervous system, should have additional clinical benefits beyond those attributable to blood pressure reduction, in protecting against hypertensive complications. Obesity-related hypertension: Understanding the neural pathophysiology of hypertension in the obese has been difficult. In normotensive obesity, renal sympathetic tone is doubled, but cardiac noradrenaline spillover (a measure of sympathetic activity in the heart) is only 50% of normal. In obesity-related hypertension, there is a comparable elevation of renal noradrenaline spillover, but without suppression of cardiac sympathetics (cardiac sympathetic activity being more than double that of normotensive obese and 25% higher than in healthy volunteers). Increased renal sympathetic activity in obesity may be a 'necessary' cause for the development of hypertension (and predisposes to hypertension development), but apparently is not a 'sufficient' cause. The discriminating feature of the obese who develop hypertension is the absence of the adaptive suppression of cardiac sympathetic tone seen in the normotensive obese. Heart failure: In cardiac failure, the sympathetic nerves of the heart are preferentially stimulated. Noradrenaline release from the failing heart at rest in untreated patients is increased as much as 50-fold, similar to the level seen in the healthy heart during near-maximal exercise. Activation of the cardiac sympathetic outflow provides adrenergic support to the failing myocardium, but at a cost of arrhythmia development and progressive myocardial deterioration. Psychosomatic heart disease: No more than 50% of clinical coronary heart disease is explicable in terms of classical cardiac risk factors. There is gathering evidence that psychological abnormalities, particularly depressive illness, anxiety states, including panic disorder and mental stress, are involved here, 'triggering' clinical cardiovascular events, and possibly also contributing to atherosclerosis development. The mechanisms of increased cardiac risk attributable to mental stress and psychiatric illness are not entirely clear, but activation of the sympathetic nervous system seems to be of prime importance.
...
PMID:Sympathetic nervous system activation in essential hypertension, cardiac failure and psychosomatic heart disease. 1134 14

Several cardiovascular disorders, including atherosclerosis, are associated with endothelial dysfunction and enhanced expression of endothelin-1 (ET-1). The role of ET-1 in the development of endothelial dysfunction in vivo remains unclear. The objective of the present study was to investigate the effect of elevated circulating levels of ET-1 on endothelium-dependent vasodilatation (EDV), and to test the hypothesis that ET(A) receptor antagonism improves EDV in patients with atherosclerosis. EDV and endothelium-independent vasodilatation were determined by brachial artery infusion of acetylcholine and sodium nitroprusside respectively during measurement of forearm blood flow (FBF) with venous occlusion plethysmography. A 60 min intra-arterial infusion of ET-1 (n=10) significantly blunted EDV in young healthy males (33 +/- 13% compared with 271 +/- 74% increase in FBF induced by 10 mug/min acetylcholine; P<0.01). Noradrenaline, which evoked a similar degree of vasoconstriction, did not attenuate EDV. In a separate set of experiments, a 60 min intra-arterial infusion of the selective ET(A) receptor antagonist BQ123 evoked a significant increase in EDV in patients with atherosclerosis (n=10; 109 +/- 45% compared with 255 +/- 101% increase in FBF induced by 10 microg/min acetylcholine; P<0.01), whereas no significant change was observed in healthy age-matched controls (n=9). Endothelium-independent vasodilatation was not affected by ET-1 or BQ123. These observations demonstrate that elevated levels of ET-1 impair EDV in healthy control subjects. Furthermore, ET(A) receptor blockade improves EDV in patients with atherosclerosis, indicating that ET-1 attenuates EDV via an ET(A)-receptor-mediated mechanism.
...
PMID:Endothelin-1 inhibits endothelium-dependent vasodilatation in the human forearm: reversal by ETA receptor blockade in patients with atherosclerosis. 1186 73

Obesity induced by long-term consumption of a fat-rich diet causes marked endothelial dysfunction. In this study we aimed to determine whether endothelial impairment is due to obesity or the diet per se. Wistar rats were fed either standard laboratory chow throughout (controls), or given a highly palatable diet (diet-fed) for 3 days, or fed the diet for 3 days and then returned to chow for 3 further days before sacrifice (diet-to-chow). Body weight, fat and gastrocnemius muscle mass, and plasma levels of glucose, insulin and leptin were all comparable between the three groups. Diet-fed rats had significantly raised plasma non-esterified fatty acids (NEFA; P=0.0005) and triglyceride levels (P=0.00001). The diet-to-chow group had intermediate plasma NEFA and triglyceride levels (significantly higher than in controls, P=0.019 and P=0.0035 for NEFA and triglycerides, respectively). There were no changes in noradrenaline and KCl responses in mesenteric arteries, whereas vasorelaxation to both carbamylcholine and sodium nitroprusside were significantly attenuated in the diet-fed group (by up to 18%; P=0.00001). Both these responses remained largely impaired in the diet-to-chow group. By contrast, histamine-induced vasorelaxation was comparable between all three groups. Thus, short-term feeding with a palatable diet induces marked endothelium-dependent and -independent arterial dysfunction. These effects occurred in the absence of obesity and largely persisted after removal of the palatable diet. Diet per se can have important detrimental effects on arterial function, which may be mediated by raised NEFA and/or triglyceride levels.
Atherosclerosis 2003 Feb
PMID:Prolonged endothelial-dependent and -independent arterial dysfunction induced in the rat by short-term feeding with a high-fat, high-sucrose diet. 1253 37

Little is known about the mechanisms converting psychosocial stress into cellular dysfunction. Various genes, up-regulated in atherosclerosis but also by psychosocial stress, are controlled by the transcription factor nuclear factor kappaB (NF-kappaB). Therefore, NF-kappaB is a good candidate to convert psychosocial stress into cellular activation. Volunteers were subjected to a brief laboratory stress test and NF-kappaB activity was determined in peripheral blood mononuclear cells (PBMC), as a window into the body and because PBMC play a role in diseases such as atherosclerosis. In 17 of 19 volunteers, NF-kappaB was rapidly induced during stress exposure, in parallel with elevated levels of catecholamines and cortisol, and returned to basal levels within 60 min. To model this response, mice transgenic for a strictly NF-kappaB-controlled beta-globin transgene were stressed by immobilization. Immobilization resulted in increased beta-globin expression, which could be reduced in the presence of the alpha1-adrenergic inhibitor prazosin. To define the role of adrenergic stimulation in the up-regulation of NF-kappaB, THP-1 cells were induced with physiological amounts of catecholamines for 10 min. Only noradrenaline resulted in a dose- and time-dependent induction of NF-kappaB and NF-kappaB-dependent gene expression, which depended on pertussis-toxin-sensitive G protein-mediated phosphophatidylinositol 3-kinase, Ras/Raf, and mitogen-activated protein kinase activation. Induction was reduced by alpha(1)- and beta-adrenergic inhibitors. Thus, noradrenaline-dependent adrenergic stimulation results in activation of NF-kappaB in vitro and in vivo. Activation of NF-kappaB represents a downstream effector for the neuroendocrine response to stressful psychosocial events and links changes in the activity of the neuroendocrine axis to the cellular response.
...
PMID:A mechanism converting psychosocial stress into mononuclear cell activation. 1257 63


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>