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)

This study was carried out to determine the evolution of atherosclerotic lesions during a therapeutic period during which regression might be appreciated. We produced aortic and coronary atherosclerosis in 27 young adult stumptail macaques (Macaca arctoides) by feeding a diet supplemented with 2% cholesterol and 25% fat. Hypertension was produced by bilateral or unilateral narrowing of the renal artery. After six months of this regimen, four monkeys were killed (group 1) and 23 monkeys were divided into three groups: group 2 received unsupplemented diet; group 3 received the same diet as group 2 and drug treatment for hypertension; group 4 was continued on the atherogenic diet and received antihypertensive drug treatment. The results indicate that deleting the atherogenic diet leads to a decrease in the lipid content of the lesions and a transformation of the lipid laden atherosclerotic plaques into lipid-poor, fibro-collagenous lesions, with a decrease in the amount of coronary luminal narrowing. Partial control of systolic hypertension by antihypertensive drugs did not accelerate the involution of the atherosclerotic lesions over the relatively short period of this study. No statistically significant correlation by regression analysis was observed between the level of blood pressure elevation, the plasma renin activity, or the degree of the drug response, and the severity and extent of the atherosclerotic lesions. Furthermore, severe arterial hypertension without an atherogenic diet (group 5) produced arteriosclerosis of the aorta, and intensified branch cushions in the coronary arteries, without inducing lipid deposition in either vascular bed.
Atherosclerosis 1978 Apr
PMID:Diet-induced atherosclerosis and experimental hypertension in stumptail macaques (Macaca arctoides). Effects of antihypertensive drugs and a non-atherogenic diet in the evolution of lesions. 9 44

Prostaglandins (PG) are highly unsaturated, cyclic fatty acids with 20 carbon atoms which are biosynthesized from dihomo-gamma-linolenic, arachidonic and eicosapentaenoic acids. These fatty acids are either ingested or are biosynthesized from linoleic and linolenic acids, respectively. The PG-precursor fatty acids are liberated from membrane phospholipids by phospholipase A and are converted to prostaglandins by the multienzyme complex PG-synthetase. The activity of the PG-system is influenced by extracellular hormonal, neural and mechanical stimuli and by intracellular factors such as ion-concentration and activity of the enzymes adenyl- and guanylcyclase. Prostaglandins are tissue hormones or autacoids which act on their receptors near their site of synthesis and degradation. The prostaglandin family constitutes a group of more than 10 natural occurring compounds showing a variety of biological actions. In arteries and veins the different PG:s have vasodilating as well as vasoconstricting effects. In addition, they are involved in the regulation of vascular smooth muscle proliferation. Within the kidney PG:s have vascular and tubular actions. They antagonize the effect of ADH, mediate renin secretion and are involved in the control of electrolyte balance. In the regulation of platelet aggregation and platelet adhesion PG:s have opposite functions: Prostacyclin which is synthesized in the vascular wall antagonizes the aggregating action of Thromboxane A2 which is formed in the platelets. A defect or an imbalance in the production of PG:s in the vascular wall, in platelets or in the kidney is assumed to play a pathogenetic role in a variety of cardiovascular and renal diseases such as in hypertension, atherosclerosis, persistent ductus arteriosus and Bartter's syndrome.
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PMID:[Prostaglandins in cardiovascular and renal function. Biochemical, physiological and clinical findings (author's transl)]. 10 97

In the present study the effect of surgery on blood pressure was investigated in 35 patients with renovascular hypertension: 17 patients with fibromuscular hyperplasia (FMD) and 18 with atherosclerosis (ASS) of the renal artery. Patients with FMD were younger (31,8 years), showed a shorter duration of hypertension (1.8 years) and were prevalently female (82%), whereas patients with ASS were markedly older (48.2 years), showed a longer duration of hypertension (2.6 years) and were most often male (78%). In both groups of patients the intravenous urogram was positive in a comparable high percentage (FMD=64%, ASS=61%). Following surgical intervention 47%(n=8) of the 17 patients with FMD were cured, 47% (n=8) were improved and only 6% (n=1) showed insufficient reduction of blood pressure values. In ASS the respective values were 28, 55 and 17%. Consequently a good effect of surgery (cured and improved) was observed in 88.5% of all patients. Patients with ASS who failed to respond to surgery (n=3) showed a remarkable long duration of hypertension (7.0 plus or minus 1.4 years). Plasma renin activity (PRA) was determined preoperatively in both renal veins in all 35 patients. From these values the PRA-ratio (PRA affected/unaffected side) was calculated. In 27 patients PRA determinations were repeated following (15 and 30 min) intravenous injection of 40 mg furosemide. PRA-ratios of larger than or equal to 1.5 were considered to be significant. In 31 patients with unilateral renovascular hypertension PRA-ratios were correlated to the postoperative blood pressure reduction. No significant differences in mean PRA-ratios were observed between cured and improved patients. Furthermore, for the total group of 31 patients no significant correlations were obtained between PRA-ratios and postoperative blood pressure reduction. Our results do not support the widespread opinion that PRA determinations in both renal veins are useful to predict the effect of surgery in patients with unilateral renovascular disease. Therefore, from our experience this method should not be recommended as obligatory in the diagnostic work-up of renovascular hypertension.
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PMID:[Renovascular hypertension. Prognostic value of renal venous renin determinations (author's transl)]. 50 54

The activity of the pituitary hormones (ACTH, STH, TTH, FSH, LH), the adrenal hormones (cortisol, aldosterone), the kidney hormone (renin), and the thyroid hormones (thyroxine tri-iodthyronine), the thyroxine binding capacity of blood proteins and the activity of the hormones of the pancreas (insulin) and the sex glands (testosterone, estradiol) were studied in 26 males suffering from ischemic heart disease verified by means of selective coronarography and in 20 healthy males with no atherosclerosis of the coronary arteries of the heart. Patients with ischemic heart disease were found to be marked by increased activity in the blood of ACTH, TTH, cortisol, aldosterone, insulin, and estradiol and reduced concentration of STH, thyroxine, and testosterone. These shifts in the activity of the hypothalamo-hypophyseal system and in its subordinate hormonal systems play an important role in the origin of the atherosclerotic process and assosiated ischemic heart disease.
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PMID:[Hormones in ischemic heart disease with the presence of coronary atherosclerosis]. 73 79

In summary, renovascular surgery has evolved during the past 20 years to become a highly efficacious therapeutic modality provided proper patient selection is practiced. Surgical techniques are now well established, and with the advent of ex vivo techniques practically any extraparenchymal renal artery lesion may be repaired. At present, much investigative work is in progress in an attempt to develop better means of selecting patients who will benefit from renovascular surgery. The newer modifications of renal vein renin assays may permit better patient selection. Many factors must be weighted when considering medical versus surgical management of hypertension. Paramount among these must be the quality of life of the patient. The inconstancy of pressure control and the frequency of undesirable side effects in the more extreme medical regimens are the primary disadvantages of nonsurgial management. An aggressive surgical approach appears to be warranted in selected patients with atherosclerosis and in almost all patients with fibromuscular dysplasia.
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PMID:Renovascular hypertension. 73 40

Fifty patients who underwent renal angiography and bilateral renal venous determinations had reconstructive or ablative surgery. The importance of stimulating renin release was underlined in 11 patients who attained a renal venous ratio greater than 1.5 to 1 only after being in an upright posture and in 5 who were studied with and without salt depletion. A protocol designed to suppress or stimulate peripheral plasma renin activity was followed in 19 patients. Stimulated peripheral plasma renin activity was not useful in identifying hypertension of renovascular origin but 10 of 12 patients whose plasma renin activity was not suppressed normally were improved by an operation. Satisfactory surgical responses were obtained in 81 per cent of the patients with unilateral and 91 per cent with bilateral atherosclerosis, and 88 per cent with unilateral and 60 per cent with bilateral fibromuscular hyperplasia. Our observations indicate that renal artery stenosis can be identified consistently only by angiography. A stimulated renal venous renin rate of 1.5 to 1 appears to have the best predictive value in surgical control of renovascular hypertension.
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PMID:Improved diagnostic accuracy of renal venous renin ratios with stimulation of renin release. 83 54

Hypertension is associated with an increased incidence of generalized vascular disease. Antihypertensive drug therapy, while decreasing overall mortality due to cerebral hemorrhage, myocardial hypertrophy or renal failure, paradoxically does not appear to reduce the incidence of coronary atherosclerosis. This study investigates whether the drugs, as a possible side effect, may have an adverse influence on the development of atherosclerotic plaques. Groups of rabbits were fed an atherogenic diet containing 1% cholesterol for 12 weeks. Two commonly used antihypertensive agents (methyldopa and chlorthalidone) were added to the diet of some groups at levels of 100 mg and 10 mg per day respectively. No significant increase in total atherosclerotic plaque area was produced by either of the drugs tested singly or in combination. Plasma renin levels were only mildly elevated and in this experimental system there was no correlation between renin activity and atherosclerotic plaque intensity. There is thus no evidence from this study that antihypertensive drugs have any adverse effects on atherosclerotic plaque formation. While the ineffectiveness of these drugs against coronary atherosclerosis may indicate that normalization of pressure cannot arrest changes already initiated, it also supports the possibility that association of atherosclerosis with hypertension may be symptomatic of a common underlying defect not correlated by normalizing blood pressure.
Atherosclerosis 1977 Jan
PMID:Anti-inflammatory agents in experimental atherosclerosis. Part 2. Failure of antihypertensive drugs to exacerbate atherosclerotic plaque formation. 83 50

Plasma renin activity (PRA) stimulated by upright posture was measured, in 300 men aged 45-64 years, by a radio-immunoassay of angiotensin I. The subjucts examined were divided into six groups, comparable in mean age, each containing 50 subjects: group 1, normotensives without manifest atherosclerosis; group 2, normotensives with angina pectoris definite; group 3, normotensives with a history of a transmural myocardial infarction; groups 4 to 6, patients with benign essential hypertension, without manifest atherosclerosis in group 4, with angina pectoris in group 5 and with a history of myocardial infarction in group 6. Significant differences in mean PRA were found between corresponding groups of hypertensives and normotensives, the values in hypertensives being lower. The precentage of low renin values was higher in hypertensives with ischaemic heart disease than in other groups. An analysis of 3-year cardiovascular mortality revealed no significant difference in mortality due to ischaemic heart disease between high-renin and low renin sub-groups.
Atherosclerosis 1977 May
PMID:Plasma renin activity in men with relation to the presence of ischaemic heart disease. 85 14

Plasma renin activity (PRA) stimulated by upright posture was measured in 300 men aged 45-64 years using a radioimmunoassay of angiotensin-I. The examined subjects were normotensive or patients with benign essential hypertension and were divided into 6 groups according to the absence of manifest atherosclerosis, the presence of definite angina pectoris or a history of myocardial infarction. Each group contained 50 unselected subjects, with a comparable mean age. Significant differences in mean PRA were found between corresponding groups of hypertensives and normotensives, the values in hypertensives being lower. The percentage of low renin values was higher in hypertensives with ischaemic heart disease than in other groups. It is suggested that this finding might be explained by functional disturbances in the kidneys in hypertensives with ischaemic heart disease.
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PMID:Plasma renin activity in patients with ischaemic heart disease. 87 44

The examination was conducted in 142 patients with coronary atherosclerosis, aged 33 to 74 years, and in 40 normal persons, aged 25 to 48 years. The pain form of the disease was observed in 96 patients, the arrhythmic one--in 38, the painless one--in 8 patients. The arterial pressure was within the normal limits in the examined patients. In 67.6% of the patients hypercholesterolemia was diagnosed, in 47.3%--hypertriglyceridemia. Type II hyperlipoproteinemia was found in 67.6% of the cases, types III and IV--in 5.3 and 9.1%, respectively, type V--in 0.5% of the patients; the type of hyperlipoproteinemia could not be identified in 10.6%, and in 6.9% of the cases the blood level of lipoproteins did not differ from the normal. The plasma renin activity examined by the radioimmunoassay in normals comprised 1.26 +/- 0.21 ng/ml/hour; in patients with the pain form of coronary atherosclerosis--6.67 +/- 0.72 ng/ml/hour; in those with arrhythmias--6.89 +/- 1.20 ng/ml/hour; in those with the painless form--2.39 +/- 1.02 ng/ml/hour. The highest renin activity was revealed in types IIa, IIb and III hyperlipoproteinemia, as well as in paroxysmal arrhythmia and cardiac fibrillation.
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PMID:[Plasma renin activity in patients with coronary arteriosclerosis with different types of hyperlipoproteinemia]. 96 46


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