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)

Hypertension is an important cardiovascular risk factor. High blood pressure per se is not a disease but a hemodynamic alteration associated with vascular disease. Two classes of drugs are especially effective in lowering blood pressure and preventing cardiovascular complications, angiotensin converting enzyme (ACE) inhibitors and calcium antagonists. The hemodynamic effects of ACE inhibitors and calcium antagonists are complementary. While ACE inhibitors inhibit the renin-angiotensin system and reduce sympathetic outflow, calcium antagonists dilate large conduit and resistance arteries. Certain calcium antagonists, such as verapamil, lower heart rate. In the blood vessel wall, the local vascular effects of ACE inhibitors and calcium antagonists are also complementary. While ACE inhibitors inhibit activation of angiotensin I into angiotensin II and prevent the breakdown of bradykinin (which stimulates nitric oxide and prostacyclin formation), calcium antagonists inhibit the effects of vasoconstrictor hormones such as angiotensin II at the level of vascular smooth muscle by reducing calcium inflow and facilitating the vasodilator effects of nitric oxide. Calcium antagonists reduce smooth muscle cell proliferation and atherosclerosis. In hypertensive animals, verapamil and trandolapril normalize endothelial dysfunction. In large angiographic trials, nifedipine and nicardipine reduced the development of new atherosclerotic plaques. After myocardial infarction, verapamil reduces mortality and cardiac events in patients without heart failure. In contrast, ACE inhibitors are effective after myocardial infarction in patients with impaired left ventricular function. Urinary albumin excretion rate decreases during ACE inhibitor therapy or with a calcium antagonist such as verapamil; combination of the two drugs has an additive effect. In resistance arteries, hypertension is associated with an increased media/lumen ratio. ACE inhibitors, but not beta-blockers, markedly improve these structural changes. In summary, ACE inhibitors and calcium antagonists have a complementary profile, both in their hemodynamic and local vascular action. Hence, combination therapy with these two classes of drugs appears particularly useful in patients with hypertension, not only to lower blood pressure, but hopefully to achieve improved cardiovascular protection.
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PMID:Vascular protective effects of ACE inhibitors and calcium antagonists: theoretical basis for a combination therapy in hypertension and other cardiovascular diseases. 856 68

The mechanisms through which hypertension contributes to the occurrence of myocardial infarction should be discussed from two points of view: (1) common risk factors for the two diseases, such as genetic risk, insulin resistance, sympathetic hyperactivity, and vasoactive substances such as angiotensin K, and (2) linking factors that are induced by hypertension and contribute to the development of atherosclerosis and myocardial infarction, such as atherosclerosis and left ventricular hypertrophy. Mechanical stress on blood vessels because of high blood pressure is an especially important factor in endothelial dysfunction, the progression of atherosclerosis, and plaque rupture. This article concentrates on these factors from the perspective of their relationship with the renin-angiotensin system, because recent multicenter trials have demonstrated that angiotensin-converting enzyme inhibitors are effective for preventing recurrence of myocardial infarction.
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PMID:Links between hypertension and myocardial infarction. 867 59

Angiotensin formed in the renin-angiotensin system is involved in the genesis and development of atherosclerosis and coronary heart disease. It has a negative impact on the process of ischaemization/reperfusion. The renin-angiotensin system is activated during a new myocardial infarction and has an impact on the process of remodelling of the left ventricle after myocardial infarction which causes its dysfunction and heart failure. ACE inhibitors are one of the important means which influence the formation of angiotensin II and thus prevent its action on heart and vessels. They prevent the development of atherosclerosis, reduce the extent of necroses during myocardial infarction and reduce the extent of left ventricular dysfunction. They diminish also stunning of the heart muscle during ischaemia/reperfusion and significantly prolong the patients life after infarction. They do not influence the development of restenosis after percutaneous transluminal angioplasty. ACE inhibitors have a positive effect on heart failure, they reduce the rate of reinfarctions and the mortality rate.
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PMID:[Angiotensin converting enzyme inhibitors in ischemic heart disease]. 901 29

Understanding the pathophysiology, diagnosis, and management of renovascular hypertension (RVH) is of paramount importance due to the severity of hypertension (HT) and renal insufficiency (RI). Moreover, adequate treatment by surgery and/or endovascular intervention can improve HT and revert RI. The comprehension of the pathophysiology of RVH had its origin on the experiments of Goldblatt which led to the recognition of the renin dependent, volume dependent, and mixed types. A continuum seems to exist, from an acute phase, supported by the endocrine renin angiotensin aldosterone system, evolving towards a chronic phase sustained by the local renin angiotensin system. The involved vasoconstrictor and mitogenic mechanisms may contribute to the arterial remodeling. The most common forms of pathology, i.e. atherosclerosis, fibromuscular dysplasia (FD), and Takayasu's arteritis, and their natural history, are described. The prevalence of RVH, ranging from 0.2% to more than 25%, depending on the clinical situation, is evidenced. Clinical symptoms and signs and the most important diagnostic tests are pointed out: functional tests (captopril test, postcaptopril renography, scintigraphy, and renin determinations) and anatomical tests (intravenous digital angiography and intrarterial angiography). New imaging techniques are also referred. A diagnostic work-up based on the index of clinical suspicion is described. The therapeutic goal is the resolution of the two main problems of RVH: hypertension and ischemic nephropathy. Revascularization is becoming mandatory either by percutaneous transluminal angioplasty mostly for FD and atheromatous non-ostial stenoses, or by surgery, which is preferred for patients with ostial or peripheral stenoses, aneuryms, occlusions and concomitant aortic disease. A better knowledge of RVH allows, not only diagnosis and treatment of one of the most frequent types of secondary hypertension, but also the control of the resulting ischemic nephropathy.
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PMID:[Renovascular arterial hypertension. From physiopathology to therapy]. 870 4

The activation of the renin-angiotensin system has been proposed as a very important step in the pathogenesis of atherosclerosis. Accordingly, ACE-inhibitors and angiotensin II receptors antagonists showed their ability to reduce the atherosclerotic process in animals. Inhibition of renin-angiotensin system reduces the development of atherosclerotic lesion either in cholesterol-fed animals and in animals after vascular injury. The precise mechanism for this action may depend on the inhibition of other than hypertensive property of angiotensin II.
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PMID:[Anti-atherosclerotic action of ACE inhibitors. I. Inactivation of the renin-angiotensin system]. 884 24

Genetic variations in the renin-angiotensin and kallikrein-kinin systems could prove to be significant pathophysiological mechanisms affecting coronary heart disease (CHD), particularly given the powerful vasoactivity of products such as angiotensin II and bradykinin. Indeed, studies show that angiotensin converting enzyme (ACE) gene polymorphism is associated with an increased risk of myocardial infarction and death, even in otherwise low-risk subjects. Genetic differences do not appear to be a risk factor for atherosclerosis or hypertension, however. Because ACE polymorphism modulates local production of angiotensin II, a powerful coronary vasoconstrictor, it may influence left ventricular mass in general as well as in coexisting disease states such as hypertension and cardiomyopathy. However, further study is needed to clarify the implications of ACE polymorphism in patients with left ventricular hypertrophy. Interactions between ACE and angiotensin II type-1 receptors may have clinical implications for preventing and managing CHD. Screening for genetic risk, as evidenced by certain variants in receptor coding sequence, may prove worthwhile if detrimental effects can be countered by drugs such as ACE inhibitors and angiotensin II receptor blockers. Given the important roles of angiotensin II and bradykinin as modulators of cellular growth and of vasoactivity, deleterious and beneficial effect at different stages of the atherosclerotic process and during acute events leading to myocardial infarction or sudden death can be suspected.
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PMID:Angiotensin I converting enzyme gene polymorphism and coronary heart disease. 886 31

A minimum level of blood pressure is necessary for atherosclerosis to develop, even in the presence of hypercholesterolemia. Experimentally and clinically we have both examples of atherosclerosis in which hypercholesterolemia is the dominant pathogenetic factor and others in which hypertension prevails (BBWT). The pathogenetic role of hypertension may be direct (wall stress) or mediated through humoral factors which characterize the different types of hypertension (renin, angiotensin, cathecholamines, endothelin, aldosterone). Probably, different forms of atherosclerosis will be identified in the future, with a different prognosis and therapeutical approach.
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PMID:Hypertension and atherosclerosis. 887 35

Most patients with hypertension in the United States have essential (primary) hypertension (95%), the cause of which is unknown. The remaining 5% of adults with hypertension have the secondary form of hypertension, the cause and pathophysiologic process of which are known. Internists and other primary care physicians refer to this as treatable or curable hypertension, because the hypertension can be managed or even controlled with medications. Similarly, the condition is called surgical hypertension by surgeons in the belief that once the cause is determined and identified, surgical intervention will result in cure of hypertension. Secondary causes of hypertension include renal parenchymal disease, renovascular diseases, coarctation of the aorta, Cushing's syndrome, primary hyperaldosteronism, pheochromocytoma, hyperthyroidism, and hyperparathyroidism. Occasionally included in this category are alcohol- and oral contraceptive-induced hypertension and hypothyroidism, but these conditions are not discussed herein. The evaluation of secondary hypertension is of interest and can bring together different facets of anatomy, physiology, pharmacology, and radiology in the medical and surgical treatment of these disorders. Despite enthusiasm that can be generated in the evaluation of these conditions, evaluation can be expensive and should not be conducted for all patients with hypertension. Features that aid in the diagnosis of secondary hypertension include the following: 1. Onset of hypertension before the age of 20 or after the age of 50 years. The presence of hypertension at a young age may suggest coarctation of the aorta, fibromuscular dysplasia, or an endocrine disorder. Hypertension found for the first time after the age of 50 years may suggest the presence of renovascular hypertension caused by atherosclerosis. 2. Markedly elevated blood pressure or hypertension with severe end-organ damage, as in grade III or IV retinopathy. These findings suggest the presence of renovascular hypertension or pheochromocytoma. 3. Specific body habitus and ancillary physical findings. For example, truncal obesity and purple striae occur with hypercortisolism, and exophthalmos is associated with hyperthyroidism. 4. Resistant or refractory hypertension (poor response to medical therapy usually necessitating use of more than three antihypertensive medications from three different classes). 5. Specific biochemical test that suggest the existence of certain disorders, such as hypercalcemia in hyperparathyroidism, hyperglycemia in Cushing's syndrome and pheochromocytoma, and unprovoked hypokalemia with renin-producing tumors, primary hyperaldosteronism, or renin-mediated renovascular hypertension. 6. Other characteristics that may suggest secondary hypertension such as abdominal diastolic bruits (renovascular hypertension), decreased femoral pulses (coarctation of the aorta), or bitemporal hemianopias (Cushing's disease). A combination of a good history and physical examination, astute observation, and accurate interpretation of available data usually are helpful in the diagnosis of a specific causation.
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PMID:Secondary hypertension: evaluation and treatment. 894 19

It is recognized that heart failure in patients with atherosclerotic lesion is the result of ischemia. However, there may also be cardiac cell dysfunction independent of ischemia, as factors advancing both of atherosclerosis and heart failure are discovered. The renin-angiotensin system is one of factor and angiotensin-converting enzyme inhibitor (ACEi) prevents progression of atherosclerotic lesion and heart failure. To elucidate the association of atherosclerosis and cardiac cell dysfunction, we investigated the effects of ACEi on cultured cardiac myocytes. Captopril increased beta-receptor density of myocytes and augmented the response to isoproterenol. CV-3480, a ACEi, also up-regulated beta-receptors but angiotensin I, angiotensin II and angiotensin type I receptor antagonist did not. Bradykinin B2 receptor blocker, HOE140, suppressed the effect of captopril on cultured cells. The results suggest that ACEi up-regulated beta-receptors and augmented the response to beta-receptor agonist through BK potentiation.
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PMID:[Association of atherosclerosis and cardiac cell dysfunction]. 895 33

The delineation of the molecular mechanisms of cardiovascular disease is an important initial step in developing improved methods of screening and therapy. Recently, progress has been made in characterizing the molecular basis of several inherited cardiovascular diseases, particularly as to the diseases caused by defects in single gene. When the disease under study has a complex etiology with multiple genetic and environmental components, it becomes much more difficult to dissect out the genetic factors and to distinguish between causation and correlation. Gene targeting in mice provides a means to test the effect of a precise genetic change completely free from the effects of differences in any other genes. Models of several human genetic diseases have been produced by gene targeting and the resulting "knockout" mice have often confirmed that the disease is the consequence of the defect of a gene of interest. The review will focus on the how molecular genetic approach is useful to understand the basic mechanism of complex genetic diseases, including essential hypertension, atherosclerosis, congenital heart disease. Particular emphasis will be given to the renin angiotensin system because a large body of evidence indicates its greater role in the pathogenesis of many complex cardiovascular diseases than has been recognized.
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PMID:Molecular genetic approach to the pathophysiology of cardiovascular disease. 897 74


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