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

Fifty-six patients with acute glomerulonephritis were studied prospectively during 1984. Their ages ranged from 10 months to 14 years old with the peak age range between 5 to 9 years. Most of them had edema, hypertension, hematuria with or without proteinuria and had low serum complement. Azotemia was found in 45 per cent of the cases. Serologic evidence for streptococcal infection was positive in 68 per cent and only 6 per cent had positive culture. Edema and hypertension were all resolved within 2 weeks. All patients that were followed up had normal serum complement by the 6th week, normal BUN, Scr by one year. The hematuria disappeared by 6 months and proteinuria by 2 months in 50 per cent of the cases. By the 4th year only one patient had microscopic hematuria and mild proteinuria with normal serum creatinine, normotension and no edema. In conclusion, in Thailand AGN is still a common kidney disease in children but with prompt and proper treatment its prognosis is still very good.
 ...
PMID:Acute glomerulonephritis in children: a prospective study. 273 44

In normotensive rats, stimulation of renal mechanoreceptors by an increase in ureteral pressure results in a contralateral inhibitory renorenal reflex response with contralateral natriuresis. Similar effects are produced by stimulation of renal chemoreceptors by renal pelvic perfusion with 0.9 M NaCl. However, in spontaneously hypertensive rats the renorenal reflex responses to renal mechanoreceptor and chemoreceptor stimulation are impaired. The present study was performed to examine whether the renorenal reflexes were altered in two-kidney, one clip hypertensive rats, a model of hypertension in which it has been suggested that the afferent renal nerves contribute to the enhanced peripheral sympathetic nervous activity. A 0.2 mm silver clip was placed around one renal artery 4 weeks before the study. At the time of study, mean arterial pressure was 156 +/- 4 mm Hg. Renal mechanoreceptor and chemoreceptor stimulation of either the nonclipped or clipped kidney failed to affect ipsilateral afferent renal nerve activity, contralateral efferent renal nerve activity, and contralateral urine flow rate and urinary sodium excretion. Renal denervation of the nonclipped kidney increased ipsilateral urinary sodium excretion from 0.65 +/- 0.13 to 1.50 +/- 0.42 mumol/min/g and decreased contralateral urinary sodium excretion from 0.18 +/- 0.03 to 0.13 +/- 0.03 mumol/min/g (p less than 0.05). Thus, denervation of the nonclipped kidney resulted in a similar contralateral excitatory renorenal reflex response as in normotensive rats. However, denervation of the clipped kidney increased both ipsilateral and contralateral urinary sodium excretion, from 0.14 +/- 0.04 to 0.27 +/- 0.5 mumol/min/g and from 1.29 +/- 0.33 to 2.09 +/- 0.59 mumol/min/g (p less than 0.01), respectively. Taken together these data suggest that the lack of inhibitory renorenal reflexes from the clipped kidney may enhance efferent sympathetic nervous activity and thereby contribute to the hypertension in two-kidney, one clip hypertensive rats.
Hypertension 1989 Oct
PMID:Impaired renorenal reflexes in two-kidney, one clip hypertensive rats. 279 17

A comparative study of the myocyte nucleolar organizer activity (NOA) was performed on silver-stained myocardium from 6 patients who had died from the hypertension disease and 7 others patients with secondary renal hypertension non-complicated by severe coronary atherosclerosis and heart failure. In the first group, positive correlations between NOA of cardiac cells and the level of maximal diastolic pressure (r = 0.8, p less than 0.028), wall thickness of the left ventricle (r = 0.8, p less than 0.028) as well as myocardial weight (r = 1.0, p less than 0.001) were found. In the second group, on the contrary, there was a pronounced negative correlation between NOA of the myocytes and myocardial weight (r = -0.86, p less than 0.005) which may be explained partially by a primary metabolic myocardial deficiency in such patients.
 ...
PMID:[Activity of the nucleolar organizers in cardiomyocytes of patients with arterial hypertension of varying genesis]. 280 43

Arteriolar vasoconstriction, structural reductions in dilated diameter, and rarefaction have been observed in vascular beds with chronic renal hypertension. To determine their pressure or flow dependence, these functional and structural parameters were studied in the developing and chronic stages of coarctation hypertension in the cremaster muscle, a normotensive skeletal muscle bed that is protected from the effects of elevated microvascular pressures. Hypertension was produced in rats by placing a silver clip around the abdominal aorta above the branches of the renal arteries. In hypertensive rats, resting diameters were reduced in second-order arterioles after 4 and 8 wk, in third-order arterioles after 2, 4, and 8 wk, and in fourth-order arterioles after 4 and 8 wk, vs. controls. Vascular tone was elevated in second-order arterioles after 2, 4, and 8 wk and in third- and fourth-order arterioles after 8 wk in hypertensive rats. No increases in medial-intimal area were found at any stage of hypertension in any arteriolar order. The density of small arterioles (3rd-5th orders) was reduced by 20% in hypertensive rats at 8 wk but was unchanged at the other time periods. These arteriolar alterations, especially the absence of structural reductions in diameter, are attenuated compared with those observed in one-kidney, one-clip hypertension and suggest that most of the arteriolar alterations that occur in renal hypertension are pressure or flow dependent.
 ...
PMID:Attenuated microvascular alterations in coarctation hypertension. 291 85

Previous studies have shown that the spontaneously hypertensive rat (SHR) has a preference for 0.9% NaCl solution over water as a drinking fluid. This preference was decreased by chronic treatment of SHR with intracerebroventricular captopril (an angiotensin converting enzyme inhibitor). Although other strains of rats were compared to SHR, no studies, that we are aware of, have been reported in renal hypertensive rats. Wistar-Kyoto rats were sham operated or had a silver clip (i.d., 0.20 mm) placed on the left renal artery to produce renovascular hypertension. Three weeks later the rats were operated upon again to implant osmotic minipumps to deliver captopril or saline either into the right lateral brain ventricle (i.c.v.) or into the peritoneal cavity (i.p.). The rats had a choice of 0.9% NaCl or tap water during the study. Blood pressures were measured by a tail plysmographic method in the conscious rats. The rats that became hypertensive showed a marked preference for saline. Treatment with captopril i.p. (24 mumol/kg/day) stimulated preference for saline but i.c.v. treatment (24 mumol/kg/day) decreased the preference for saline despite reductions in blood pressure in both groups of renal hypertensive rats. These changes were not seen in renal hypertensive rats infused with saline. The results suggest that captopril's antihypertensive effect in this model of renal hypertension may be independent of the effects of the drug on preference to drink saline.
 ...
PMID:Central angiotensin converting enzyme blockade and salt preference in renovascular hypertensive rats. 298 3

Neural and angiotensin-mediated influences that alter hemodynamic and excretory behavior of the nonclipped kidney of two-kidney, one clip hypertensive rats were assessed by sequential acute surgical denervation of the nonclipped kidney and intravenous infusion of converting enzyme inhibitor (SQ 20881), 3 mg/kg X hr. Normal and two-kidney, one clip hypertensive rats (0.2-mm silver clip on the right renal artery 3-4 weeks before study) were prepared to allow study of each kidney. Mean arterial blood pressure of two-kidney, one clip hypertensive rats fell significantly from control values of 149 +/- 6 to 135 +/- 6 mm Hg after denervation of the nonclipped kidney. Despite this decrease in arterial pressure, the nonclipped kidney exhibited significant increases in glomerular filtration rate (from 1.00 +/- 0.08 to 1.24 +/- 0.08 ml/min), sodium excretion (from 88 +/- 39 to 777 +/- 207 nEq/min), fractional sodium excretion (from 0.06 +/- 0.02 to 0.54 +/- 0.14%), and urine flow rate (from 3.7 +/- 0.5 to 8.2 +/- 1.1 microliter/min). A significant decrease in glomerular filtration rate (from 1.12 +/- 0.07 to 0.85 +/- 0.08 ml/min) with no change in excretory function was observed for the clipped kidney following denervation of the nonclipped kidney. Intravenous addition of converting enzyme inhibitor significantly increased renal blood flow (from 7.0 +/- 1.3 to 10.6 +/- 1.5 ml/min) and sodium excretion (from 777 +/- 207 to 1384 +/- 425 nEq/min) for the nonclipped kidney; blood pressure decreased from 135 +/- 6 to 123 +/- 4 mm Hg, and renal vascular resistance decreased significantly (from 22 +/- 3 to 13 +/- 2 mm Hg X min/ml).(ABSTRACT TRUNCATED AT 250 WORDS)
Hypertension 1986 Dec
PMID:Effects of angiotensin inhibition and renal denervation in two-kidney, one clip hypertensive rats. 302 89

Although it is well known that hypertension is often associated with primary hyperparathyroidism and that parathyroidectomy reverses or reduces this abnormality, the etiology of elevated blood pressure in hyperparathyroidism is still conjectural. We have analyzed serum calcium, blood pressure, and metabolites of adrenal cortical hormones before and after surgical therapy for hyperparathyroidism in 10 normotensive and six hypertensive patients with primary hyperparathyroidism. Successful parathyroidectomy lowered serum calcium (P less than 0.01) and diastolic blood pressure (P less than 0.05) in all subjects. Mean urinary aldosterone and Porter-Silber chromagens were within normal limits preoperatively in normotensive as well as hypertensive subjects. After parathyroidectomy, aldosterone levels as well as Porter-Silber chromagens decreased significantly in all patients (P less than 0.01). However, when normotensive and hypertensive subjects were analyzed separately, the decrease in aldosterone levels was significant only in the normotensive group (P less than 0.05) whereas the decrease in Porter-Silber chromagens reached significancy only in the hypertensive group (P less than 0.01). The results indicate that surgical therapy for hyperparathyroidism lowers serum calcium and blood pressure and is associated with a decrease in the excretion of adrenal steroid metabolites. It is suggested that the temporal relationship which exists between ionized calcium and steroidogenesis in hyperparathyroid patients contributes at least in part to the generalized decrease in blood pressure observed after successful parathyroidectomy.
 ...
PMID:Adrenal responses to subtotal parathyroidectomy for primary hyperparathyroidism. 311 38

Regional variations in the size and shape of isolated myocytes were studied using the two-kidney, one clip (2K1C) renal model of hypertension. Weanling male Sprague-Dawley rats (50 to 75 g) were anesthetized by ketamine (100 mg/kg) during renal artery clipping (0.2 mm internal diameter silver clip) and were then allowed to grow for 6 to 8 weeks, when the blood pressure had stabilized at 180 mmHg. Hearts were removed, weighed and then were perfused with a calcium-free Joklik medium containing collagenase. Isolated myocytes were collected from five regions and fixed in isoosmolar glutaraldehyde: right ventricular free wall (RVFW), right and left halves of the interventricular septum (RIVS, LIVS), and epicardial and endocardial halves of the left ventricular free wall (LEPI, LENDO). Myocyte volume was measured by Coulter Counter. Myocyte length was measured by sonic digitizer. Cross-sectional area was calculated from myocyte volume and length. Tailcuff systolic pressure and heart weight were significantly increased in 2K1C rats as compared to control. Body weights were not different. Cell volume was significantly increased in RIVS, LIVS, LEPI, and LENDO, but not in RVFW. Cell length was not significantly increased in any region. Thus, the 2K1C model showed a predominant left ventricular hypertrophy in which the right half of the septum acted in concert with the left ventricle. The shape of the hypertrophied myocytes, having an increase in volume due to an increase in cross-sectional area but not length, was most consistent with a pressure-induced form of cardiac hypertrophy.
 ...
PMID:Regional myocyte size in two-kidney, one clip renal hypertension. 323 84

In Goldblatt hypertension in rats produced by implanting a silver clip on the left renal artery, captopril induces a greater difference in the 1-min uptake of diethylenetriaminepentaacetic acid (DTPA) between the two kidneys than in baseline uptakes, similar to the experiences in unilateral renovascular hypertension in man. The combination of captopril and furosemide induces an even greater difference in renal uptakes than with captopril alone in this rat model. In paired experiments, DTPA complexes were used as a standard to compare the differences in renal uptake between the two kidneys after captopril-furosemide with other existing and potential renal radiodiagnostic agents. No statistically significant difference was found between DTPA, glucoheptonate, dimercaptosuccinic acid, aminated dextran, or lysozyme. However, the differences in renal uptake were significantly less with hippuran than with DTPA. Furosemide and captopril caused delayed renal retention of hippuran after one minute. This response appeared to be due to non-specific volume depletion because it occurred in both clipped and unclipped kidneys.
 ...
PMID:Comparison of different radioactive agents for the detection of renovascular hypertension with captopril in a rat model. 328 Jul 51

A model of experimental hypertension has been developed in which the features of the two kidney-one clip and renal ablation models are combined in a single rat. It has been designated the clip-ablation model. It is produced by the placement of a silver clip with an opening of 0.13 mm on a branch of the left renal artery supplying one-third of that kidney, followed by right nephrectomy. In this way the effects of renin-dependent hypertension may be studied in glomeruli which are undergoing compensatory changes in response to reduction in renal mass. Clip-ablation rats were compared to rats with 1 1/3 reduction of renal mass at various intervals up to 28 days after operation. Systolic blood pressure rose with increasing time after operation in both groups with the increase being greater in the clip-ablation rats (177 +/- 10 mm Hg) as compared to the ablation rats (153 +/- 6 mm Hg) at 28 days. Plasma renin activity was increased slightly at 3 days in the ablation rats but had returned to normal levels by 28 days. By contrast, the plasma renin activity rose throughout the experimental period in the clip-ablation rats and attained a level of 32.3 +/- 8.0 ng/ml/hour by 28 days. Urine protein was significantly higher than normal only in the 28-day clip ablation rats (71.2 +/- 23.9 mg/24 hour). Glomerular damage index (GDI), a measure of glomerular injury, increased with longer intervals from operation in both experimental groups, paralleling the rise in systolic blood pressure. Beginning on day 14 and onward the GDI was always numerically higher in the clip-ablation rats than in the ablation rats. Stepwise multiple regression analysis indicated that the strongest predictor of GDI was the change in blood pressure. Plasma renin activity had an additional independent effect on GDI in the clip-ablation rats. The finding of more glomerular damage in the clip-ablation rats than in those with simple removal of comparable amounts of renal tissue is in contrast to the lesser amount of damage found in the two kidney-one clip model when compared with the model of removal of renal substance. It is likely that the compensatory hemodynamic changes in response to reduction in renal mass in the glomeruli of clip-ablation rats make them more vulnerable to injury when exposed to a renin-angiotensin induced hypertension.
 ...
PMID:Clip-ablation. A model of experimental hypertension in the rat. 330 50


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