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

1. Arterial endothelial cells and adventitial fibroblasts have a higher rate of renewal than medial myocytes. As has been shown for rabbit aortic endothelial cells, the decrease with age in the cell turnover os caused by both a lengthening of the cell cycle of the proliferating cells and a reduction of the growth fraction. The arterial wall cells exhibit a heterogeneous division potential which is dependent on their position within the vessel. 2. A dilation trauma caused by a balloon catheter as well as numerous exogenous (freezing, ionizing radiation, noradrenaline application) and endogenous (hypertension, hypoxia, endotoxin shock) influences bring about more or less pronounced endothelial alterations. Probably, the secondary development of fibrocellular intimal plaques is dependent on the extent of endothelial regeneration. There is a possibility that complete re-endothelialization provides some protection against the development of plaques. 3. Proliferation kinetic characteristics of intimal cells from atherosclerotic plaques tell against the development of such plaques from one cell clone. The question whether or not proliferating intimal cells are of a monoclonal or a polyclonal origin cells for further investigations. Monocytogenic and myogenic foam cells have a relatively high proliferative activity and the ability to emigrate from atherosclerotic plaques at certain stages of their development. The "response-to-injury" hypothesis of atherosclerosis put forward by Ross (1977), which corresponds to the view held by European authors that atherosclerosis is a modified form of wound healing, is supported by the proliferation kinetic behaviour of vascular wall cells.
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PMID:Proliferation, migration and cell renewal within the arterial wall. 640

To determine the time course of changes in arterial stiffness and corresponding morphology during atherosclerosis progression, we determined pulse wave velocity (PWV) in cynomolgus monkeys fed atherogenic (test) and control diets over an 18-month period. At 6-month intervals, thoracic and abdominal aortic PWVs were determined with a pressure transducer retracted down the aorta in 5 cm increments. Iliac artery PWV was determined from the abdominal aortic pressure to a noninvasive femoral pulse. Groups of individual cardiac cycles, triggered by the ECGs, were sampled on a computer and the velocities (PWV) of the pulse wave fronts were calculated. There was no significant difference between groups until 18 months when test animal PWVs in the thoracic (7.44 +/- 0.83 m X s-1) and abdominal (8.52 +/- 0.67 m X s-1) aorta were significantly greater than those of controls (5.02 +/- 0.51 and 6.24 +/- 0.53 m X s-1, respectively), indicating increased arterial stiffness. There was no change in iliac PWV, 10.96 +/- 0.74 m X s-1 for 18-month test compared with 9.44 +/- 0.89 m X s-1 for controls. Constant infusion of nitroprusside and noradrenaline lowered and raised blood pressure and PWV in all groups, and PWV changes due to drug-induced pressure changes were greater in atherosclerotic than in control arteries. Systolic pressure of 18-month test and pulse pressure of 12- and 18-month test groups were significantly greater than controls under all drug conditions, also indicating increased vessel stiffness. Morphometric evaluation of histological aortic cross sections revealed early, noncomplicated atherosclerosis showing gradual increases in the ratio of intimal to medial cross-sectional area in the thoracic (1.24 +/- 0.30 after 18 months) and abdominal (1.70 +/- 0.42 after 18 months) aortas, compared with control ratios of essentially zero. The fraction of the internal elastic lamina covered with atherosclerotic lesions, and maximal intimal thickness also showed significant increases during the test diet period. These data show that early atherosclerosis resulted in aortic but not iliac stiffening which was detected by increased PWV before development of significant stenotic lesions.
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PMID:Pulse wave velocity and morphological changes associated with early atherosclerosis progression in the aortas of cynomolgus monkeys. 669 37

A lot of over 60 atherosclerotics with clinical manifestations of senile depressive illness was studied comparatively with a lot of subjects of the same age with essential arterial hypertension (EAH). As concerns the behaviour of the catecholamine content in CSF and blood, the total catecholamines are approxiately equal in the two lots, but with a clear difference of the catecholamine fractions. The CSF catecholamines behaviour in old atherosclerotics is characterized by the presence of increased values of noradrenaline (NA) and of adrenaline (A), with increased statistical significance, but without modifications of the adrenaline percentage (A %) from the total catecholamines, comparatively to the values found in normal subjects. The serotonin (5-HT) content of the CSF in men with atherosclerotic senile depressive illness was lower even than in subjects with coronary atherosclerosis. In atherosclerosis protides modifications precede the histologic changes. In CSF, GLU, ALA, TYR increase in old subjects. In blood, GLU, ALA, TYR, HIS, LEU, SER increase in the same subjects. ARG decreases with age. THR is higher in men than in women. In the urine of all the men as well as of all the women of more than 60 years, GLN and ALA have increased values. LYS increases with age. GLN and ARG are higher in men than in women.
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PMID:Pattern of the cerebrospinal fluid (CSF) and blood biogenic amines and of the CSF, blood and urine amino acids as pathogenetic ground of the senile depressive illness. 677 91

The effects of noradrenaline (NA), sodium nitrite (NaNO2) and isosorbide dinitrate (ISDN) on the steady state distribution of 125I-labelled albumin in the wall of excised rabbit common carotid arteries were studied. The vessels were incubated in Tyrodes solution either at relaxed length and zero transmural pressure (non-pressurized) or at in vivo length and a transmural pressure of 70 mm Hg (pressurized). Label was applied in the same concentration at both the luminal and outer surfaces. The mean medial uptake in pressurized vessels was greater after treatment with 10(-7) M NA than after additional treatment with either 10(-3) M NaNO2 or 10(-3) M ISDN. The opposite was found for non-pressurized vessels. The medial uptake by NA-treated pressurized vessels was greater than that by NA-treated non-pressurized vessels, while the reverse was found for NaNO2- or ISDN-treated vessels. We conclude that the different patterns of uptake seen in these vessels results from the relative effects of externally applied stress (elongation and pressurization), smooth muscle tone and convection through the wall, on the properties of the interstitium, and possibly from the effects of the vasoactive agents on endothelial permeability.
Atherosclerosis 1983 Jan
PMID:Effect of noradrenaline, sodium nitrite and isosorbide dinitrate on albumin transport in the wall of the excised rabbit common carotid artery. 683 86

Experiments were undertaken on excised rabbit common carotid arteries to assess whether the distribution volume for radioactively labelled albumin is influenced by smooth muscle tone or externally applied stress. In arteries at relaxed length and zero transmural pressure, the distribution volume in the media was reduced by noradrenaline at concentrations exceeding 10(-9) M and increased by both sodium nitrite and isosorbide dinitrate at concentrations exceeding 10(-4) M. The distribution volume was lower in both the media and adventitia of segments at in vivo length pressurized with air to prevent convection through the wall, than in segments at relaxed length and zero transmural pressure. Noradrenaline decreased and sodium nitrite increased the medial distribution volume of the tracer in these air-pressurized segments. The vasoactive agents did not change the [51Cr]EDTA space in vessels at relaxed length and zero transmural pressure, although there were small alterations of medial water content. Transient conditions raise interpretative difficulties because of uncertainty about endothelial permeability and time-dependent changes of wall properties. The changes of the distribution volume for labelled albumin are thought to reflect changes in the properties of the interstitium.
Atherosclerosis 1983 Jan
PMID:Effect of vasoactive agents and applied stress on the albumin space of excised rabbit carotid arteries. 683 90

In order to explain whether the arterial smooth muscle exhibits altered contractile properties in atherosclerosis, normal and atherosclerotic rabbit aortic strips were exposed to noradrenaline (NA) and potassium chloride (KCl). The experiments were repeated with normal blood and the containing an excess of free fatty acids (FFA) added to the bath. Contraction induced by NA was markedly enhanced in the atherosclerotic trips. In contrast the response of atherosclerotic aorta strips to KCl was reduced. Excess FFA blood added to the bath with NA normalized the previously enhanced contractile response in atherosclerotic aortic strips. An opposite change in KCl induced contraction was observed under the some conditions namely increased response occurred. We conclude that the enhanced reaction of atherosclerotic aortic strips to NA depending on a specific mechanism might be reversed by elevation of FFA in blood.
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PMID:The contractile response of the normal and atherosclerotic aortic strips to noradrenaline, and potassium ions. 718 19

Norepinephrine (NE) accumulation, dose response to NE and NE content were studied in the aortas of White Carneau (WC) and Show Racer (SR) pigeons in order to determine if a correlation exists between the atherosclerosis susceptibility of WC and atherosclerosis resistance of SR with the degree of sympathetic nerve ending activity. In addition, the age factor was included by comparing results in 4-14 month-old and 5-year-old animals. NE accumulation by abdominal aorta samples from SR pigeons of both age groups and by thoracic segments from 5-year-old SR was significantly higher than that by WC pigeon samples. The difference in NE accumulation had lower P-values in older than in younger pigeons. Maximal contraction of SR abdominal aorta was significantly higher than that of WC samples. The ED50 to exogenous NE decreased with age in both strains but the decrease was statistically significant only in WC strain. Finally, NE content of abdominal aorta segments was significantly higher in SR than in WC pigeons. Ne content of thoracic aorta did not differ in the 2 strains. The results complement our previous work indicating that sympathetic nerve endings in the vessel wall may have a trophic influence which modulates the metabolic pattern of the arteries. Thus, atherosclerosis and perhaps age, are related degenerative vascular changes associated with reduced indices of sympathetic activity.
Atherosclerosis 1981 Apr
PMID:Genetic difference in the sympathetic nervous activity and susceptibility to atherosclerosis in pigeon. 724 88

The polyene fatty acid composition of cardiac phospholipids is modified by age, diet and stress in the rat. In the aging heart there is a progressive replacement of 18:2n6 by 20:4n6 in phosphatidylcholine (PC) and a replacement of 18:2n6 by 22:6n3 in phosphatidylethanolamine (PE). Norepinephrine stress accelerates aging of cardiac PC and PE. Dietary fish oil causes a replacement of 18:2n6 and 20:4n6 by 22:6n3 in cardiac PC and PE but not in cardiolipin. Studies on human cardiac autopsy samples suggest that: (a) polyene fatty acid composition changes with age; (b) stability of cardiac phospholipids is a function of the fatty acid composition, chain length and unsaturation; (c) coronary atherosclerosis is associated with a reduced content of 18:2n6 in phospholipids, an increased content of glycerides of abnormal composition and an unexpectedly low level of free fatty acids (FFA) in the heart muscle, and (d) many cases of sudden cardiac death in the absence of marked coronary artery stenosis or myocardial infarction may be associated with significant alterations in myocardial levels of FFA (increase) or PE (decrease).
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PMID:Pathophysiology of long-chain polyene fatty acids in heart muscle. 745 29

Normal aging is associated with different changes in the cardiovascular system that lead to an increase in pathological processes, such as hypertension, coronary artery disease, heart failure, and postural hypotension with enhancement of both morbidity and mortality. The vascular alterations consist of changes in the function and structure of the arteries, and increasing vascular stiffness, mainly when atherosclerosis is present, whose incidence is increased with age. The arteries accumulate lipids, collagen, and minerals. Cerebral perfusion may be reduced in the elderly, mainly regional cerebral blood flow, which leads to a deterioration of mental and physical functions. The degree of deterioration is increased when aging is associated with hypertension. Aging alters endothelial cells, which play an important role in vascular tone regulation. Such a process tends to reduce endothelium-dependent relaxations, and clearly reduces the vasodilation elicited by beta-adrenoceptor agonists. The contractions induced by different agents, such as 5-hydroxytryptamine, histamine, high potassium and angiotensin are barely affected with aging, whereas those elicited by noradrenaline or endothelin are usually reduced. However, plasma noradrenaline levels are increased with age, mainly due to a reduction in the sensitivity of presynaptic alpha 2-adrenoceptors and also of noradrenaline uptake. Sodium pump activity, that controls cellular ionic homeostasis, may be altered depending on animal species. Finally, vascular Ca2+ regulation appears to be altered and the extracellular Ca2+ dependence of contractile responses elicited by agonists is increased, which justifies the enhanced sensitivity to Ca2+ antagonists in senescence.
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PMID:Age-related changes in vascular responses: a review. 761 68

The pathogenesis of Raynaud's disease is unclear; an enhanced response to catecholamines has been hypothesised to contribute to this vasospastic disorder. Impaired endothelium-dependent dilation occurs in other diseases associated with vasospasm, such as coronary atherosclerosis. We investigated both endothelium-dependent and endothelium-independent venodilatory function in Raynaud's disease using the hand-vein compliance technique. Full dose-response curves to noradrenaline were constructed in 10 subjects with primary Raynaud's disease and 10 age and sex matched control subjects. The two groups did not have a different response to noradrenaline. Mean (SD) log values of ED50s (the dose producing half maximum response) were 1.00 (0.59) (geometric mean 10 ng/min) in Raynaud's disease compared with 1.29 (0.66) (20 ng/min) in control subjects (p = 0.16). The efficacy of noradrenaline as a venoconstrictor was similar in the two groups: mean maximum dilation (Emax) to noradrenaline was 81 (14)% in the Raynaud's group and 89 (8)% in the control group (p = 0.08). Full dose-response curves to the endothelium-dependent dilator bradykinin were constructed. Emax to bradykinin was significantly lower in the Raynaud's group than in the control group (65 [21] vs 91 [29%], p = 0.02). ED50 values (doses producing half maximum response) for bradykinin were similar in the two groups. Maximum dilation with nitroprusside, a direct releaser of the vasodilator nitric oxide, was not diminished in the Raynaud's group (94 [23] vs 102 [15]% in controls, p = 0.26). These results suggest that endothelium-dependent venodilation is impaired in peripheral vessels in Raynaud's disease, possibly due to diminished release of nitric oxide, and may contribute to the pathogenesis of the disorder.
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PMID:Venodilation in Raynaud's disease. 790 47


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