Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022672 (acute tubular necrosis)
 2,175 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The actions of L-channel calcium antagonists on the kidney are the result of direct and indirect effects. The direct effects are characterized by vasodilation, especially when the renal vascular resistance was enhanced beforehand. The increase in glomerular filtration rate is small and transient in most of the clinical trials with chronic administration. An important direct effect of calcium channel antagonists on renal function is the increase of sodium and water excretion by a tubular action that occurs in the absence of hemodynamic changes. The mechanism of the tubular effects of calcium channel antagonists is not understood at present. An indirect effect of calcium channel antagonists on the kidney is the inhibition of the aldosterone secretion by the adrenals. A sodium and water loss due to inhibition of tubular reabsorption leads to an increase in renin activity and aldosterone concentration in the plasma as seen typically with diuretics. The dissociation of renin- and aldosterone increase by calcium channel antagonists is a new finding and contributes favorably to the anti-hypertensive efficacy of calcium channel antagonists. In experimental acute renal failure mainly diltiazem and verapamil improved recovery of kidney function. In kidney transplantation, diltiazem reduced posttransplant acute tubular necrosis and improved primary graft function. It remains to be seen whether other calcium channel antagonists have a similar beneficial therapeutic effect in pathological states of renal function.
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PMID:Renal actions of calcium channel antagonists. 207 37

Reperfusion injury is increasingly recognized as a key factor in the development of posttransplant acute tubular necrosis. Previous studies have shown that addition of the calmodulin inhibitor trifluoperazine (TFP) to Collins' flush solution protected the cortical microcirculatory integrity and dramatically improved renal viability after transplantation. The present report describes the protective effect(s) of TFP in the course of reperfusion injury. Twenty mongrel dogs underwent bilateral nephrectomy; in each instance, the left kidney was flushed immediately with 250 ml of cold Collins' solution, and the right kidney was flushed with the same solution containing TFP, 5 mg/L. After 48 and 72 hr of preservation, each kidney was connected through silastic shunts to the femoral vessels of another dog. The mean renal blood flow (RBF) immediately after reperfusion was 2.2 ml/g/min and 1.7 ml/g/min in the left and right kidneys, respectively, and was similar to mean RBF measurements prior to nephrectomy. After 15 min of reperfusion, there was a sharp decrease in mean RBF in the Collins' flushed kidneys, which persisted after 60 min of reperfusion (0.37 ml/g/min). In contrast, there was only a mild decrease in mean RBF in the TFP-flushed kidneys (1.27 ml/g/min). A partial explanation for the favorable effect of TFP may be related to the inability of the ischemic cell to handle the increased calcium load associated with reperfusion (calcium paradox). In a test of this possibility, 0.5 mg/kg of verapamil, a calcium channel blocker, was infused during reperfusion. No beneficial effects of this drug were noted in either Collins' or TFP-flushed kidneys (n = 10). However, when 1.25 mg/kg of captopril, an angiotensin-converting enzyme inhibitor, was infused at the time of reperfusion, a dramatic amelioration of the reperfusion injury occurred in the Collins' flushed kidneys (1.2 ml/g/min) (n = 10). Taken together, these data suggest that the damage to cold-preserved kidneys flushed with Collins' solution alone may occur at the time of actual reperfusion. Such reperfusion damage is ameliorated by TFP and captopril. The known relationship between calcium and the effect of angiotensin on the vascular smooth muscle cell may explain in part the protective role of calcium inhibitors placed in preserved kidneys prior to reperfusion.
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PMID:The protective effect of calcium inhibitors and of captopril on the renal microcirculation during reperfusion. 309 41

Renal hypoperfusion such as occurs in shock creates an environment in which cellular injury and organ dysfunction can occur during the episode of shock as well as during reoxygenation and reperfusion. A severe decrement in oxygen delivery compromises energy (adenosine triphosphate) production, leading to various degrees of cell injury ranging from cell swelling to acute cortical necrosis. These different responses of the kidney to shock explain the multiple clinical presentations varying from an isolated loss of concentrating ability to prolonged anuria. Many cellular events contribute to renal cell injury, including cellular ATP depletion, cellular and mitochondrial calcium overload, and activation of phospholipases and oxygen radical formation. Recent clinical and experimental studies suggest that ATP-MgCl2, free radical scavengers, diuretics, vasodilators, and calcium channel blockers appear to be beneficial in preventing acute tubular necrosis after anoxic or severe hypoxic insults. Thus these agents may be helpful in altering the course of acute renal failure in shock patients and may decrease their morbidity and mortality.
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PMID:Renal response to shock. 377 12

Nifedipine caused acute, reversible deterioration in renal function in four patients with chronic renal insufficiency. The absence of hypotension, clinical course, benign urinary sediments, and normal results of renal ultrasound examinations excluded acute tubular necrosis, pyelonephritis, interstitial nephritis, obstructive uropathy, and acute glomerulonephritis. It is postulated that this slow calcium channel blocker produced deleterious intrarenal hemodynamic alterations in the setting of moderate to severe renal functional impairment. Nifedipine may alter renal function by blocking calcium entry into renal vascular smooth muscle, thereby reducing the efficacy of vasoconstrictor hormones in regulation of renal blood flow and glomerular filtration rate. An alternative explanation is that nifedipine may inhibit the compensatory synthesis of vasodilatory prostaglandin E2 analogous to the clinical observation of acute deterioration in renal function by nonsteroidal anti-inflammatory drugs in patients with pre-existing renal insufficiency. These observations suggest that clinicians should monitor renal function closely and exercise caution when administering nifedipine to patients with underlying renal insufficiency.
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PMID:Nifedipine-induced renal dysfunction. Alterations in renal hemodynamics. 649 46

In 212 cyclosporine-treated renal transplant recipients with stable graft function at 1 year and with potential follow-up of 5 years the prevalence of arterial hypertension was 81.6% at 1 year and 81.2% at 5 years. The logistic regression analysis showed that the presence of hypertension before transplantation (P = 0.0001; odds ratio 3.5), a plasma creatinine level higher than 2 mg/dL at 1 year (P = 0.0001; odds ratio 3.8), and a maintenance therapy with corticosteroids (P = 0.008; odds ratio 3.3) were positively associated with hypertension at 1 year after transplantation. The mean number of graft failures between 1 and 5 years was significantly higher and the mean reciprocal of plasma creatinine was significantly worse at 1 and 5 years in patients with noncontrolled hypertension than in normotensive patients or in patients with hypertension well controlled by drugs. We also investigated the potential protective role of nifedipine. The episodes of acute tubular necrosis (four versus three), of acute rejections (28 versus 29), the mean arterial pressure at 1 year (105 +/- 9 versus 104 +/- 9 mm Hg) and 5 years (105 +/- 10 versus 108 +/- 12 mm Hg), and the mean plasma creatinine level at 1 year (1.4 +/- 0.4 versus 1.6 +/- 0.4 mg/dL) and 5 years (1.8 +/- 1 versus 1.9 +/- 1 mg/dL) were similar in 52 patients who were given nifedipine for at least 4 years and 58 hypertensive patients who never took calcium channel blockers.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hypertension after renal transplantation. 849 23

Due to a shortage of suitable kidneys for transplantation there has been an increase in the use of kidneys taken from old and marginal donors, which has led to a high incidence of acute tubular necrosis. Several reports suggest that the administration of calcium channel blockers improves the initial function after renal transplantation. We conducted a randomized, double-blind placebo-controlled trial to study the effect of the calcium channel blocker gallopamil on the incidence and course of acute tubular necrosis following cadaveric renal transplantation. A trend developed showing a decrease in episodes of acute tubular necrosis in gallopamil versus placebo, and became statistically significant when the outcome of kidneys from donors older than 50 years was analyzed separately [gallopamil 6/14 (42%) vs. placebo 10/11 (91%), P <0.01 corrected chi2]. We conclude that pre-transplantation renal graft perfusion and post-transplantation recipient treatment with gallopamil reduces the incidence of post-transplantation acute tubular necrosis, particularly in kidney taken from older donors.
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PMID:Gallopamil reduces the post-transplantation acute tubular necrosis in kidneys from aged donors. 900 65

This review evaluates the various causes and management of acute renal failure (ARF) in children. ARF is defined as an abrupt decline in the renal regulation of water, electrolytes and acid-base balance, and continues to be an important factor contributing to the morbidity and mortality of critically ill infants and children. The common causes of ARF in children include acute tubular necrosis secondary to various causes (including congestive heart failure and sepsis), haemolytic uremic syndrome, and glomerulonephritis and urinary tract obstruction. Ischaemia, toxins (including drugs) as well as primary parenchymal disease, have to be considered and ARF can also be a complication of systemic disease. The basic principles of management are avoidance of life-threatening complications, maintenance of fluid and electrolyte balance, and nutritional support. Only a few patients require specific management of the underlying disorder, although it is important to diagnose these conditions. Knowledge about the use of drugs for the prevention of ARF is scarce. Mannitol, low-dose dopamine, calcium channel antagonists, atrial natriuretic peptide and albumin have been evaluated and, where possible, meta-analyses are cited. Mannitol treatment appears to be warranted prophylactically after paediatric renal transplantation. Albumin infusion can reverse prerenal ARF in children with nephritic syndrome. For treatment of the complications of hyperkalaemia and volume overload, salbutamol, insulin and glucose infusion and diuretics such as furosemide and sodium bicarbonate, are discussed. All of the major dialysis modalities (peritoneal dialysis, haemodialysis and continuous haemofiltration) can be used to provide equivalent solute clearance and ultrafiltration. The indication for, and the choice of the modality depend on the patient requirements and on local resources, and should involve the care of a paediatric nephrologist. Peritoneal dialysis requires minimal equipment and infrastructure, is easy to perform and remains the favoured modality of renal replacement therapy in children. However, continuous haemofiltration is an excellent alternative to peritoneal dialysis in patients with ARF and severe fluid overload. Dialysis remains the most important tool to bridge the time needed for recovery of renal function. There is increasing evidence that more intense use of dialysis may improve the overall prognosis.
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PMID:Acute renal failure in children: aetiology and management. 1173 64

Nephrotic syndrome (NS) is frequent in renal transplant recipients and may be related to a large variety of glomerular lesions. In some of these cases, the transplant biopsy showed no significant glomerular changes and the NS was reversible, but the primary renal disease was not minimal change disease (MCD), suggesting that MCD may develop de novo in renal transplant setting. Knowledge of this entity, however, is limited. Among 67 cases of post-transplant NS encountered in a 12-yr period, five were found to be associated with de novo MCD. A critical review of the literature revealed nine additional cases of de novo MCD. The data from these 14 cases show that patients with de novo MCD had a large variety of primary renal diseases but MCD or focal segmental glomerulosclerosis was not among them. Eight of the 14 transplanted kidneys (60%) were from living related donors, suggesting this as a risk factor. Nephrotic range proteinuria (3-76 g/d) developed immediately or shortly after transplantation (within 4 months for all reported cases, except for one at 24 months). The serum creatinine when NS was first diagnosed was normal or mildly elevated, but acute renal failure occurred in three patients. On biopsy, the glomeruli were normal or, more frequently, displayed mild, focal segmental mesangial sclerosis, hypercellularity, deposition of IgM/C3, or accumulation of mononuclear inflammatory cells in some glomerular capillaries. The tubulointerstitial compartment was normal in cases with normal renal function; displayed mild acute and/or chronic rejection that correlated with a mildly elevated serum creatinine; or showed acute changes including acute rejection, acute tubular necrosis, or acute cyclosporin A toxicity, which accounted for both acute renal failure at presentation and its subsequent reversibility. Under various treatments, including increased steroids, angiotensin converting enzyme inhibitors, calcium channel blockers and angiotensin receptor blockers, sustained remission of NS was achieved in 13 cases, within a year (0.5-12 months) in 10 and later (24, 34 and 98 months, respectively) in three. In the remaining case, the patient died of septic shock 2 months after transplantation. After remission of the NS, the grafts functioned well without or with minimal proteinuria for several years. De novo MCD has characteristic clinical and pathologic features. It represents an important but hitherto underemphasized cause of post-transplant NS, which is potentially reversible and does not adversely affect the renal transplants.
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PMID:De novo minimal change disease associated with reversible post-transplant nephrotic syndrome. A report of five cases and review of literature. 1222 32

Many antihypertensive agents have been demonstrated to assist in preservation of kidney function, among them those that modulate calcium channels. Calcium channel blockers may also be of value in protecting hemodialysis patients from complications of sepsis. In diabetic recipients of kidney transplant allografts treated with cyclosporine, calcium channel blockade has been retrospectively linked to improved graft preservation and to fewer episodes of sepsis. This brief review outlines clinical and experimental publications on potential protection from sepsis by addition of calcium channel blockers to standard antibiotic therapy in individuals who may or may not have normal kidney function, or in the presence or absence of immunosuppression. Such mechanisms include blockade of antibiotic cytosolic extrusion in the cases of Pneumococci, Mycobacterium tuberculosis, Plasmodium falciparum malaria, or Schistosoma mansoni; blockade of the calcineurin/calmodulin pathway (in immunosuppressed patients allowing for lower dosage of cyclosporine); stabilization of calcium movement at the level of sarcoplasmic reticulum by which shock (vasopressor instability) is prevented; or of cytosolic calcium influx and cell death (in the case of allograft acute tubular necrosis). Given the high cost of development of new antibiotics, a role for generic calcium channel blockade in sepsis prevention should be pursued by additional studies to investigate potential links between blockade of calcium channels and expression of sepsis in at-risk populations.
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PMID:Does calcium channel blockade have a role in prevention of expression of sepsis in renal transplant recipients? 2792 May 69