Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0033687 (proteinuria)
 24,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To explore the role of systemic hematocrit in the vascular adaptations which characterize desoxycorticosterone-salt hypertension, studies were performed in three groups of rats with uninephrectomy, desoxycorticosterone administration, and 1% saline in the drinking water. One group received recombinant human erythropoietin to increase hematocrit, and another group was subjected to phlebotomy and fed a low-iron diet to induce anemia. Control rats exhibited systemic and glomerular capillary hypertension, proteinuria, and substantial glomerular sclerosis at 8 wk. Erythropoietin modestly increased hematocrit and blood pressure and substantially aggravated glomerular capillary pressure, proteinuria, and glomerular sclerosis. In contrast, reduction of hematocrit with a low-iron diet significantly attenuated systemic and glomerular hypertension, proteinuria, and sclerosis. It was concluded that the pace of progression of glomerular injury can be limited by chronic reduction in hematocrit, which effectively ameliorates both systemic and glomerular hypertension in this model of salt-sensitive hypertensive renal disease.
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PMID:Anemia ameliorates progressive renal injury in experimental DOCA-salt hypertension. 176 13

In this study, the effect of the antihypertensive agents nifedipine (4.5 mg/day) and hydralazine (50-200 mg/l of drinking water) on the progression of chronic renal failure and scarring was evaluated in rats submitted to subtotal (5/6) nephrectomy (SNx). The effect of blood pressure reduction was studied in groups of rats fed either a medium-protein diet (24%) or high-protein diet (50%). SNx rats fed a high-protein diet had significantly higher levels of proteinuria and severer renal scarring at sacrifice (120 days after SNx). Nifedipine reduced proteinuria in SNx rats fed a high-protein diet. Both drugs significantly reduced systemic hypertension in SNx rats. Hydralazine and nifedipine also reduced hypertriglyceridaemia but had no effect on blood cholesterol levels. However, in spite of adequate control of systemic hypertension with the agents studied, the severity of renal scarring (glomerular sclerosis or tubulo-interstitial scarring) was not affected by treatment. We confirm that the control of systemic hypertension is not sufficient to prevent renal scarring in rats submitted to extensive renal ablation.
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PMID:Effect of antihypertensive therapy in experimental chronic renal failure. 182 85

To establish if the benefit of angiotensin converting enzyme inhibitor therapy in retarding progressive diabetic renal injury is due to a specific intrarenal effect of the systemic hypotensive effect, we studied the effect of long-term ramipril treatment on blood pressure, glomerular filtration rate, and urinary protein excretion in streptozotocin-diabetic spontaneously hypertensive rats. The hypotensive effect of ramipril was prevented by a high salt diet, which did not alter the degree of renal angiotensin converting enzyme inhibition. Three weeks after uninephrectomy and induction of diabetes, rats were allocated to three groups. Groups 1 and 2 were given 1% NaCl, whereas group 3 was given water as drinking solution. One week later, groups 2 and 3 received 0.4 mg/kg/day ramipril in their drinking solution, which was continued over a 2-month period. Ramipril produced a blood pressure fall only in water-drinking rats (group 3) despite a similar reduction in plasma and renal angiotensin converting enzyme activity in groups 2 and 3. Salt-loaded rats had a progressive increase in urinary protein excretion over the duration of study. Ramipril treatment prevented an increase in protein excretion only in animals given water and with a reduced systolic blood pressure. Glomerular filtration rate was similar in all three groups. Ramipril treatment improved animal survival independently of a reduction in blood pressure or an effect on proteinuria. Although it is possible that angiotensin converting enzyme inhibitors have specific intrarenal effects reducing progression of diabetic proteinuria, concomitant control of systemic blood pressure appears to be necessary to demonstrate a benefit.
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PMID:Salt blocks the renal benefits of ramipril in diabetic hypertensive rats. 182 92

Plasma values of atrial natriuretic factor (ANF) were evaluated in 31 women with pregnancy-induced hypertension (PIH) and 31 normal pregnant women at the same age of gestation. In 27 women with PIH and 27 normal pregnant women forearm venous tone (FVT) was evaluated by Strain Gauge Plethysmography. Forearm vascular resistance (FVR) was measured as the ratio of mean blood pressure (MBP) to forearm blood flow. In addition Cardiac Index (CI) by means of transthoracic electrical bioimpedance and total peripheral vascular resistance (TPR) (with the Frank Equation) were also measured. In comparison with the normal pregnant women, the women with PIH had similar values of hematocrit (as an index of plasma volume) and significantly higher levels of FVR and TPR, while ANF plasma values did not differ significantly. Subdividing the women with PIH in relation to the presence of proteinuria (greater than or equal to 0.3 g/l), those with proteinuria, in addition to significantly higher levels of FVR and TPR, had significantly higher levels of FVT than normal pregnant women, while ANF plasma values were higher even though the difference was only near the level of significance. Hypertensive women with proteinuria also had higher values of FVT than hypertensive women without proteinuria. By means of multiple regression ANF did not show any significant correlations with hematocrit or sodium excretion. Hypertension with proteinuria seems to represent a more severe form of the disease in which, in addition to the probable influence of other factors such as the renin-angiotensin and prostaglandin systems, a greater increase in peripheral sympathetic tone than in hypertension alone appears to be present, causing a reduction in venous compliance in addition to the elevation in FVR and TPR, with increase in central blood volume and atrial stretch. This may explain the higher ANF plasma levels in these patients in comparison with normal pregnant women, even though the absence of a significant correlation of ANF with hematocrit and the fact that ANF increase was only near the level of significance may suggest a change in the relation between ANF secretion and atrial volume receptors in pregnancy either normal or complicated by hypertension. ANF does not seem to play an important role in water and sodium excretion in PIH probably because of the presence of very high plasma levels of hormones such as aldosterone, progesterone and oestriol which, together with renal prostaglandins, seem to be involved in diuresis and natriuresis in pregnancy.
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PMID:Plasma concentrations of atrial natriuretic factor and hemodynamics in pregnancy-induced hypertension. 183 84

We present a radiometric assay for the determination of urinary angiotensin-converting enzyme activity, using benzoyl-[1-14C]glycyl-L-histidyl-L-leucine as the substrate. An optimal pH of 8.3, an optimal chloride concentration of 0.375 mol/l and complete inhibition by EDTA-Na2, captopril and enalaprilat confirm the specificity of the assay. Comparison of dialysis and ultrafiltration for concentration of urine showed the existence of angiotensin-converting enzyme inhibitors in human urine. Dialysis against water was the more effective method for avoiding enzyme inhibition. After dialysis of urine, the assay was linear with time and with enzyme concentration; it was highly sensitive (60 mU/l) and showed good reproducibility. Under our technical conditions, we found angiotensin-converting enzyme activity in urine samples with quantitatively abnormal protein contents, but not in normal urine. Urinary angiotensin-converting enzyme did not correlate with proteinuria nor with water-salt parameters or creatinine. We confirm the kidney tubular epithelial origin of the enzyme, and propose the use of our assay to study urinary angiotensin-converting enzyme as a marker of renal tubular damage.
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PMID:A reliable radiometric assay for the determination of angiotensin I-converting enzyme activity in urine. 196 95

Because experimental studies of kidney aging are frequently complicated by the presence of renal disease, we set out to define a model minimizing renal pathology and thus revealing basic aging phenomena. Male and female Wistar/Lou rats were conceived, born, and bred to 42 months in a specific pathogen-free husbandry. They had free access to water and to a protein diet containing 2% fish and 15% vegetable proteins. The mean survival ages of this colony were 39 months for females and 35 months for males. Body weight, 24-hour food and water intake, urinary volume, and solute excretion were measured every 6 months in a group of 12 males and 12 females. Throughout the study, the mean body weight remained close to 180 gm in females and 320 gm in males. Despite this size difference, absolute daily food intake was similar in the two sexes and almost constant over the studied period. Age-related changes in proteinuria and phosphate excretion were greater in males than in females. Decreased urine osmolality and increased urinary volume, on the other hand, were more pronounced in old females than in males. Renal loss of calcium was noticed in both sexes and glucosuria remained discrete. Kidneys examined at 12, 24, and 36 months in both sexes and also at 42 months in females were free of major pathology such as pronounced glomerulosclerosis, tubular nephrosis, tubular cast, or hydronephrosis. In the oldest animals a few foci of interstitial inflammation occasionally were seen. The sole significant morphologic change was a regular but moderate thickening of the glomerular basement membrane, which roughly doubled its size from 12 to 36 months. Morphometric studies failed to demonstrate an increase in mesangial matrix or mesangial cellularity. No changes in foot processes, slit diaphragms, or endothelial fenestrae were seen with increasing age. These observations indicate that basic age-related changes in kidney structure and function of rats fed ad libitum can be reduced to a few parameters provided that adequate strains, diet, and husbandry conditions are selected for experimentation.
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PMID:Longitudinal study of solute excretion and glomerular ultrastructure in an experimental model of aging rats free of kidney disease. 200 55

Angiotensin converting enzyme (ACE) inhibitors, particularly enalapril and captopril, have been shown to decrease proteinuria in diabetic animals and human subjects. Since heparan sulfate proteoglycan confers a negative charge on the glomerular basement membrane, and either decreased synthesis or loss of this charge causes albuminuria in diabetic animals, we examined the possibility that enalapril prevents albuminuria through glomerular preservation of heparan sulfate in long-term diabetic rats. A total of 22 male Wistar rats were used in the study. Diabetes was induced in 15 rats by a single intraperitoneal injection of streptozotocin (60 mg/kg). The remaining 7 rats received buffer. One week following induction of diabetes, 8 diabetic rats were allowed to drink tap water containing enalapril at a concentration of 50 mg/liter; the remaining 7 diabetic and 7 nondiabetic rats were given only tap water. The drug treatment was continued for 20 weeks. Systolic blood pressure and 24-hr urinary excretion of albumin were measured at 2, 8, 16, and 20 weeks. At the end of 20 weeks, all rats were killed, kidneys were removed, and glomeruli were isolated by differential sieving technique. Total glycosaminoglycan and heparan sulfate synthesis was determined by incubating glomeruli in the presence of [35S]sulfate. Characterization of heparan sulfate was performed by ion-exchange chromatography. Systolic blood pressures were significantly lower in enalapril-treated diabetic rats compared to untreated diabetic rats. Diabetic glomeruli synthesized less heparan sulfate than glomeruli from nondiabetic rats. Also, glomerular heparan sulfate content of diabetics was significantly lower than that of nondiabetics. Further characterization of heparan sulfate showed that the fraction eluted with 1 M NaCl was significantly lower and the fraction eluted with 1.25 M NaCl significantly higher in diabetic than in normal rats. Enalapril treatment normalized not only glomerular synthesis and content but also various fractions of heparan sulfate in diabetic rats. Diabetic rats excreted increased quantities of heparan sulfate and albumin than nondiabetic rats. Enalapril therapy prevented both these increases in diabetic rats. These data suggest that enalapril treatment improves albuminuria through preservation of glomerular heparan sulfate and prevention of its urinary loss in diabetic rats.
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PMID:Enalapril improves albuminuria by preventing glomerular loss of heparan sulfate in diabetic rats. 201 5

We studied the effects of difluoromethylornithine (DFMO), an experimental drug that inhibits the biosynthesis of natural polyamines, on anti-DNA antibody production, immunoglobulin synthesis, proteinuria, and blood urea nitrogen (BUN) in lupus-prone female NZB/W mice. Administration of 1% of the drug in drinking water reduced anti-DNA antibody levels by about 80% of that of untreated mice of the same strain. There was a reduction of IgG and IgA levels in older DFMO treated mice, whereas IgM level was not affected. Proteinuria and BUN were also significantly reduced in treated mice. Moreover, DFMO treatment reduced the concentration of putrescine and spermidine in spleen cells. Our results suggest that polyamine biosynthesis inhibition by DFMO may provide a new approach to the treatment of lupus.
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PMID:Difluoromethylornithine therapy of female NZB/W mice. 202 14

The relationship between tubulointerstitial nephritis and proteinuria was characterized in experimental nephrosis in rats. In one group, proteinuria induced by aminonucleoside of puromycin (PAN) was reduced by using an 8% protein diet and adding the angiotensin I-converting enzyme (ACE) inhibitor enalapril to the drinking water. Two control groups were injected with saline and PAN, respectively, and fed a 27% protein diet. The first group had significantly reduced albuminuria and a definite attenuation of tubular cell injury. There was a strong positive correlation between the number of interstitial macrophages and albuminuria. The beneficial effect was reproduced by dietary-protein restriction alone, whereas ACE inhibition alone had an insignificant effect on the degree of proteinuria. Depletion of circulating T lymphocytes in one group of nephrotic rats eliminated interstitial lymphocytes but did not affect interstitial macrophage influx. Inhibition of the in situ proliferation of resident interstitial macrophages by unilateral kidney irradiation failed to change the intensity of the macrophage infiltration. Treatment of rats with sodium maleate produced proximal tubular cell toxicity but interstitial inflammation did not develop, suggesting that the latter is not a nonspecific response to tubular injury. These studies demonstrate a strong relationship between tubulointerstitial nephritis and the severity of proteinuria in experimental nephrosis.
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PMID:A relationship between proteinuria and acute tubulointerstitial disease in rats with experimental nephrotic syndrome. 202 4

N,N'-Dimethylaminopropionitrile (DMAPN), a major component of the NIAX catalyst ESN, is known to cause urinary bladder dysfunction in exposed workers. In order to investigate the mechanism of DMAPN toxicity, we carried out time-course (0-72 h) and dose-response (175-700 mg/kg) studies on the effects of DMAPN in rats and mice. Treated animals exhibited several signs of toxicity including loss of body weight, reduced water consumption, and bladder urine retention, as well as bladder injury. DMAPN-induced bladder injury was characterized by distended bladders with marked diffuse submucosal and subserosal edema, petechial hemorrhage, and multifocal perivascular inflammatory infiltrates. The qualitative and quantitative analysis of urine indicated hypoosmolality, aciduria, hematuria, proteinuria, and oliguria. Elevated levels of creatinine and urea levels in plasma were indicative of renal dysfunction. Within hours following DMAPN administration, the animals exhibited a significant increase in urinary retention that resolved between 60 and 72 h. Rats excreted about 44% of the administered DMAPN dose unchanged in the urine, while mice excreted only about 6% of the dose. Commercially available DMAPN metabolites, administered by gavage, produced toxic effects less adverse than DMAPN. The biochemical effects of DMAPN included depletion of glutathione and increased lipid peroxidation in target organs, including urinary bladder and kidney. These studies indicate that there are species differences in DMAPN toxicity. The differences may be due to differences in the formation of reactive metabolic intermediates of DMAPN.
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PMID:Studies on the mechanism of urotoxic effects of N,N'-dimethylaminopropionitrile in rats and mice. 1. Biochemical and morphologic characterization of the injury and its relationship to metabolism. 203 40


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