Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of polyarteritis nodosa (PN) in childhood involving various organs such as the gastrointestinal tract, skin, CNS, kidneys and liver with hypogammaglobulinemia is reported. This 6 month old girl was admitted to our hospital with vomiting, diarrhea, bloody stools with mucous and weight loss. For the past 5 months she had these abdominal symptoms. She was diagnosed as having PN of the Kussmaul-Maier variety on the grounds of the biopsy of skin lesion where a necrotizing vasculitis was found. Prednisolone and methylprednisolone pulse treatment were not effective in suppressing the progress of the disease. At the age of 1 year 7 month a combination therapy of prednisolone and immunosuppressants (cyclophosphamide) was started and this was found to be effective. She was discharged when she was 2 year and 2 month. The dosage of prednisolone was tapered as the activity of the PN decreased and she did well with a maintainance dosage of 9.5 mg/day. At 3 year 6 month of age she suddenly developed hypertension (the plasma renin activity was found to be 16.6 ng/m/hr. and the aldosterone 220 ng/dl). CNS involvement such as spinal cord dysfunction, left sided convulsions, cerebral hemorrhage developed 5 months later. Methylprednisolone pulse therapy was performed 3 times and 2 mg/kg/day of prednisolone was administered. In spite of this therapy she passed away with a massive cerebral hemorrhage at the age of 4 year 8 month. Unfortunately an autopsy was not performed. Results of the immunological tests proved that the hypogammaglobulinemia was a common variable immunodeficiency (CVI). It has been reported that primary immuno-deficiency syndrome is often associated with collagen disease and auto-immune disease. This lack of the defense mechanism against the virus or extra antigen could be related to the onset of collagen and auto-immune disease. As the correlation between CVI and PN has not been clarified this case is of interest as concerns the cause of PN.
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PMID:[A case of hypogammaglobulinemia associated with polyarteritis nodosa presenting a variety of symptoms in childhood]. 197 16

The presence of left ventricular hypertrophy (LVH) is of poor prognosis in essential arterial hypertension, but it may regress under antihypertensive treatment. Angiotensin-converting enzyme inhibitors, calcium antagonists, centrally acting antihypertensive agents and beta-blockers with low intrinsic sympathomimetic activity constantly reduce the left ventricular mass. This stands in contrast with diuretics and vasodilators which induce stimulation of the sympathetic and/or renin-angiotensin systems and usually have no effect on LVH. Animal experiments have shown that regression of LHV has no adverse effect on the myocardial changes aimed at correcting the LVH-associated abnormalities (collagen content, changes in isomyosins, density of beta-adrenergic receptors, etc.) and that it improves the coronary haemodynamics disturbed by LVH. In clinical practice, reducing the ventricular mass does not modify the left ventricular systolic function, usually improves the diastolic function precociously altered by LVH and seems to reduce the LVH-induced ventricular hyperexcitability. The regression of LVH under antihypertensive treatment should result in a lesser cardiovascular risk in hypertensive patients.
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PMID:[Regression of left ventricular hypertrophy with antihypertensive treatment]. 197 67

The biochemical mechanisms by which hypertension accelerates atherosclerosis and increases the risk of aortic aneurysm rupture are poorly understood. This study evaluates the effects of hypertension on aortic trace element concentrations and antioxidant status in tissue removed from 26 normotensive (NT) and 20 hypertensive (HT) patients. Twenty-seven of 46 patients (59%) had aneurysmal (AA), and 19 of 46 (41%) had occlusive disease (OD). Aortic iron concentrations were markedly higher in both OD and AA tissue compared with controls. A similar trend was observed with copper concentrations, with the highest elevations observed in HT AA tissues. No significant differences were observed in zinc concentrations, except that HT AA aorta had significantly lower zinc levels than either OD or control tissue. Aortic ascorbic acid concentrations in diseased aorta were lower than those of controls, but independent of blood pressure. Copper-zinc-superoxide dismutase activity was similarly reduced, with the lowest activity observed in diseased aorta from HT patients. Only HT AA aorta had significantly higher manganese-superoxide dismutase activity than controls. The aortas of patients with AA had significantly lower amounts of elastin and greater elastase activity than either controls or those with OD. However, the differences were independent of blood pressure. Hypertensive patients with OD and AA had 31% more and 27% less aortic collagen, respectively, than their NT counterparts (P less than 0.05). These data suggest that the reduction in aortic collagen and elastin in HT patients with AA compared with their NT counterparts may explain the larger size of aneurysms and predispose to their eventual rupture. Furthermore, the diminished antioxidant status associated with HT predisposes to lipid peroxidation, which contributes to the acceleration of these processes. Our studies were conducted in patients with established aortic aneurysmal and occlusive disease. Whether these observations are pertinent to the pathogenesis of AA and OD remains unclear and merits further study.
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PMID:Effects of hypertension on aortic antioxidant status in human abdominal aneurysmal and occlusive disease. 199 4

Relative 125I-albumin concentration was measured in vivo in the aortic media of sham-operated (n = 10) and hypertensive (two-kidney, one clip) rats, untreated (n = 8) or treated (n = 10) by an angiotensin converting enzyme inhibitor (CEI, Trandolapril). Blood pressure was acutely lowered to a normal level at the time of the experiment in hypertensive rats (n = 7) to separate the direct effect of increased pressure from the effect of pressure-induced structural changes. Relative tissue concentration profiles of labeled albumin across the media were obtained using a serial frozen-sectioning technique. In hypertensive rats, the mean medial albumin concentration decreased by 35% in the ascending arch and 32% in the descending arch (p less than 0.01). When blood pressure was acutely lowered in hypertensive animals, this value decreased further by 56% in the ascending arch, 48% in the descending arch (p less than 0.01), and 22% in the thoracic aorta (p less than 0.05) as compared with controls. The medial thickness in hypertensive rats was significantly increased (more in the ascending arch than in the rest of the aorta). Four-week CEI treatment reversed hypertension and medial thickening, but the mean medial albumin concentration remained significantly lower in the arch (by 36% in the ascending part and 40% in the descending part, p less than 0.01). The collagen content in the thoracic aorta was significantly increased in hypertensive rats (by 40%, p less than 0.01) and remained increased (by 29%, p less than 0.01) after CEI treatment. These results suggested that the hypertension-induced structural changes might reduce the medial distribution volume for albumin, whereas elevated blood pressure per se tended to enhance albumin concentration within the media. However, the net result of chronic hypertension was a reduction of the mean medial albumin concentration. The aortic arch appeared to be more affected than the rest of the aorta. Fiber content, more than medial thickness, might be responsible for the observed differences in albumin concentration. Lowering of blood pressure seemed to be insufficient to restore normal albumin concentration profiles and perhaps those of other macromolecules. This finding may be relevant in evaluating some of the complications associated with hypertension.
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PMID:Reduction of transmural 125I-albumin concentration in rat aortic media by chronic hypertension. 199 51

Progressive myocardial fibrosis, including the accumulation of collagen within the adventitia of intramyocardial coronary arteries, is seen in the hypertrophied rat myocardium secondary to renovascular hypertension (RHT) and has been held responsible for alterations in myocardial diastolic stiffness. This study was undertaken to test the hypothesis that this presumptive angiotensin-aldosterone mediated fibrosis and its functional consequences could be favorably altered by an antihypertensive oral dose (50 mg/kg/day) of the angiotensin converting enzyme (ACE) inhibitor captopril. Three groups were studied: control; untreated RHT for 8 weeks; treated RHT, with captopril started 48 h before banding and continued for 8 weeks. Interstitial collagen volume fraction and perivascular collagen area (morphometry), the fibrillar nature of collagen (picrosirius polarization), and the end diastolic stress-strain relation of the intact left ventricle were examined in each group. In comparison to untreated animals with RHT, we found that captopril, begun prior to banding, attenuated interstitial and perivascular fibrosis and prevented hypertrophy and the rise in diastolic stiffness 8 weeks later. Thus, an adverse accumulation of collagen in the interstitium and around intramyocardial coronary arteries, and its functional consequences in the rat with RHT, can be prevented by captopril. Other ACE inhibitors may have similar salutary effects, but remain to be evaluated. The pathogenetic origin of myocardial fibrosis in RHT requires further investigation, but appears to be related to the angiotensin-aldosterone system.
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PMID:Coronary vascular remodeling and myocardial fibrosis in the rat with renovascular hypertension. Response to captopril. 200 97

Arterial compliance describes a change in the volume of arteries following a change in blood pressure. The physical basis of the compliance concept and experimental procedures in animals both indicate that the relation between arterial compliance and blood pressure pattern is often unclear. Compliance is pressure-dependent because of the biphasic elastin and collagen composition of arteries and, hence, decreases when blood pressure increases. Compliance also determines the pulsatile amplitude of the pressure wave by regulating the buffering function of an artery's face to the cardiac pump and, accordingly, its reduction induces a selective increase in systolic level. The questions are whether these theoretical and experimental phenomena can be extrapolated to human hypertension and whether they can be assessed from indirect measurement of arterial compliance by means of a time-domain analysis of arterial pressure and flow waves via various models of the arterial tree. Whatever the method and site of measurement, arterial compliance was found to be decreased in different forms of hypertension. This low compliance can be considered to have a causal role in elderly patients with isolated systolic hypertension. In contrast, in patients with systolo-diastolic hypertension physiologic and pharmacologic arguments exist against the fact that low arterial compliance may be the pure consequence of mean blood pressure elevation. Moreover, it is suggested that aging acts in concurrence with pressure elevation to decrease arterial compliance, and that in certain hypertensive patients additional factors, perhaps atherosclerotic in nature, contribute to impair the elastic properties of arteries.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Use of arterial compliance for evaluation of hypertension. 200 4

ION typically affects the older population with a sudden decrease in vision, altitudinal visual field loss, and a swollen optic nervehead. Systemic hypertension and diabetes mellitus are the most commonly associated medical problems. Occlusion of the posterior ciliary arterial blood supply to the retrolaminar optic nerve leads to axoplasmic stasis and further compromise of vessels in the nerve substance, which causes the typical funduscopic appearance. Although there is no recognized medical treatment that can reverse the visual loss, a recent report suggests optic nerve sheath decompression for a select group of patients with a gradual decline in vision due to ION may be beneficial. When ION occurs in persons less than 50 years of age, such etiologies as juvenile diabetes mellitus, antiphospholipid antibody-associated clotting disorders, collagen-vascular disease, and migraines should be considered. Rarely, complications of intraocular surgery or acute blood loss may cause an ischemic event in the optic nerve.
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PMID:Ischemic optic neuropathy. 201 Nov 5

In chronic models of hypertension such as the spontaneously hypertensive rat (SHR), thickening of the media of large arteries occurs mainly through smooth muscle cell (SMC) hypertrophy accompanied by DNA replication resulting in large polyploid cells. In resistance vessels of SHR, medial hypertrophy occurs through a hyperplastic response. It has been suggested that this hyperplasia is due to mitogens such as platelet-derived growth factor (PDGF), while the hypertrophied polyploid cells occur from stimulation by angiotensin II from within the vessel wall. Angiotensin II activates many of the same cellular pathways as PDGF, including stimulation of phospholipase C, mobilization of intracellular calcium and activation of Na+/H+ exchange. Both induce transient increases in the proto-oncogenes c-fos and c-myc. However, a possible explanation for the difference in SMC response may be involvement of an intracellular pathway stimulated by PDGF (but not by angiotensin II), such as stimulation of JE (a cytokine-like molecule), which may activate transcriptional events necessary for mitogenesis. In atherosclerosis vascular hypertrophy occurs in the form of focal intimal thickening and results from hyperplasia of diploid SMC and their greatly increased production of extracellular matrix, (particularly collagen) and the accumulation of intra- and extracellular lipid. The SMC involved in atherogenesis are phenotypically modified compared with the SMC of undiseased regions, and amongst other features have a lower volume fraction of myofilaments (Vvmyo). Associated with modulation to a low Vvmyo are increases in SMC expression of mRNA for collagens type I (alpha 1 and alpha 2) and type III (alpha 1), elastin, fibronectin, as well as massive increases in collagen protein (26- to 45-fold), glycosaminoglycans (5-fold), and lipid accumulation (7-fold).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Molecular biology of vascular hypertrophy. 203 94

Three nonelderly patients without hypertension whose clinical and radiologic features otherwise resembled Binswanger's subcortical arteriosclerotic encephalopathy underwent biopsy of the hyperintense periventricular lesions seen on magnetic resonance imaging. The pathologic findings of the periventricular lesions consisted of gliosis with mild rarefaction and edema of the white matter. All patients had a sclerosing vasculopathy of unknown cause, which involved numerous small vessels within the periventricular lesions. The vessels stained negatively for amyloid, amyloid precursors, desmin, vimentin, keratin, immunoglobulin, and complement. On electron microscopy, small arteries, arterioles, venules, and capillaries were characterized by swollen astrocytic foot processes surrounding the vessels; dense, perivascular collagen packing; crystalline arrays of filaments within basement membrane; giant lipid-laden lysosomes within perivascular cells; and narrowing of the vascular lumina. Similar changes were not seen in a control group of 19 patients. The pathologic features of the vessels in these cases are distinct from the vasculopathy associated with Binswanger's subcortical arteriosclerotic encephalopathy. We suggest that a spectrum of vasculopathies may be associated with dementia and periventricular hyperintense lesions on magnetic resonance imaging.
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PMID:Sclerosing vasculopathy of the central nervous system in nonelderly demented patients. 203 86

Vision is often threatened by a number of systemic diseases. The author details the effects of diabetes, hypertension, atheroma and collagen diseases on the eye.
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PMID:An eye on systemic disease. 203 97


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