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

The effect of transient renal ischemia on renal concentration and distribution of 99mTc-HEDP, 99mTc-DMSA, and 99mTc-DTPA was compared in rabbits with acute tubular necrosis. Scintigrams were obtained after injection in normal rabbits or ones with unilateral or bilateral ischemia. 99mTc-HEDP concentration in ischemic tissue was 8 to 18 times normal 1--4 hours after injection, and the resulting images delineated the morphological changes in the ischemic kidneys more accurately than those obtained with DMSA or DTPA. Calcium concentration in the ischemic kidneys increased sixfold. 99mTc-HEDP may be useful in evaluation of renal failure secondary to tubular injury.
 ...
PMID:Renal hyperconcentration of 99mTc-HEDP in experimental acute tubular necrosis. 22 Jun 70

A 42-year-old male was hemodialyzed for 2 years with excellent control of calcium-phosphate metabolism. He received a cadaveric renal transplant but experienced a prolonged episode of acute tubular necrosis during which he could not tolerate phosphate-binding antacids. His calcium X phosphate product became markedly elevated for 20 days. Following a brief period of function, the homograft was removed on the 45th post-transplant day after severe rejection and subsequent infection. Chest X-ray was normal. Six days after graft nephrectomy, he became acutely dyspneic and markedly hypoxemic. Diffuse, flocculent pulmonary infiltrates appeared on the chest film. The patient expired 1 day later. At postmortem examination, there was severe, diffuse pulmonary alveolar calcification demonstrated by chemical and histologic examination. Although unlikely, the prolonged post-transplant period characterized by elevated calcium X phosphate product may have played a pathogenetic role. Calciphylaxis may have occurred, with hyperparathyroidism as the sensitizing agent and any of several drugs acting as challenger.
 ...
PMID:Sudden fatal pulmonary calcification following renal transplantation. 33 63

Cadaver renal transplantation was performed in a 14-year-old girl with primary hyperoxaluria. Acute tubular necrosis was present initially, and a moderate rejection crisis occurred at 6 weeks. Renal biopsy performed at 4 months showed considerable deposition of calcium oxalate. Urinary excretion of oxalate varied between 315-371 mg/24 hr per 1.73 m2 (normal less than 50 mg). Despite these unfavourable factors, renal function has remained stable for the last 2 1/2 years; the serum creatinine is 1.5 mg/100 ml at 3 years. This is the longest surviving graft reported so far in documented primary hyperoxaluria. Graft failures in previous reports could in part be explained by additional complicating factors. It is concluded that renal transplantation is not necessarily contraindicated in primary hyperoxaluria.
 ...
PMID:Prolonged survival after renal transplantation in primary hyperoxaluria of childhood. 34 53

Tetraethyl orthosilicate (Si(OC2H5)4, or TEOS) is a silicon-containing compound which has widespread industrial applications and which has been documented as biohazardous. The histopathological features and mechanism of TEOS toxicity in the kidney of ICR mice were investigated in a light and electron microscopy study, which included energy dispersive X-ray microanalysis. TEOS was given to mice as intraperitoneal injection of approximately 1,670 mg/kg body weight in experiments based on a 24 h time-scale. Tissues were examined after sampling either immediately on death if this occurred within 24 h or, in the case of surviving animals, after sacrifice at 24 h. Renal injury was considered to be the most probable cause of death, on the basis of the following main findings: 1) acute tubular necrosis (glomerular lesions were absent); 2) a dense deposit of silicon over the microvilli of dead tubular epithelial cells; 3) an abundant aggregation of hydroxyapatite crystals containing calcium in the cytoplasm and mitochondria of the dead tubular epithelial cells; and 4) abundant myelinosomes and some hydroxyapatite crystals in the cytoplasm of viable proximal convoluted tubule epithelial cells. It was speculated that silicon compounds may bind to the plasma membranes of the proximal convoluted tubule epithelial cell microvilli and damage or interfere with membrane calcium channels. The resulting calcium ion imbalance may play a role in the subsequent progression of acute tubular necrosis by TEOS.
 ...
PMID:Acute renal injury by tetraethyl orthosilicate in mice: ultrastructure, histochemistry and X-ray microanalysis. 160 May 16

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.
 ...
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.
 ...
PMID:The protective effect of calcium inhibitors and of captopril on the renal microcirculation during reperfusion. 309 41

Calcium channel blockade has been shown to prevent warm renal ischemic damage. The ability of verapamil to decrease the severity of acute tubular necrosis (ATN) after 24-hr cold storage and autotransplantation was studied in a randomized paired study of 12 dogs. Experimental animals pretreated with intraarterial verapamil and flushing of the harvested kidney with cold intracellular solution containing verapamil demonstrated significantly (P less than .05) greater renal function preservation over their matched controls. A subsequent nonpaired study of 6 dogs treated only with flushing of the harvested kidney with perfusate containing verapamil demonstrated no significant preservation advantage over controls. We conclude that verapamil, administered prior to the ischemic event, can enhance the protective effect of hypothermia and decrease the severity of ATN in ischemically injured kidneys.
 ...
PMID:The effect of verapamil in reducing the severity of acute tubular necrosis in canine renal autotransplants. 330 60

In a prospective randomized trial we evaluated the influence of the calcium antagonist diltiazem (Dil) on the development of acute tubular necrosis (ATN) in cadaveric kidney transplantation. Dil was added to Eurocollin's solution (20 mg/l) at donor nephrectomy. The graft recipient received a preoperative bolus injection of Dil (0.28 mg/kg) which was followed by an infusion of Dil (0.0022 mg/min/kg) for 2 days. Thereafter, Dil was applied orally. Immunosuppressive therapy consisted of ciclosporin (CS) and low-dose steroids. There were no significant differences between the groups with respect to donor characteristics, HLA matching and ischemic periods. In the control group (n = 22), 9 patients (41%) developed ATN compared to 2 patients (10%) in the Dil group (p less than 0.05). In the control group, 3.5 +/- 0.4 HD per patient were necessary compared to 0.6 +/- 0.2 in the Dil group (p less than 0.05). Although CS blood levels were significantly higher in the Dil group (1st week 1,150 vs. 728 ng/ml; p less than 0.01), the GFR of grafts with primary function was significantly higher in the Dil group (day 7:39 vs. 24 ml/min; p less than 0.05). A significant reduction of the CS dose by 30% (p less than 0.01) led to comparable CS levels. In the Dil group, significantly fewer rejection episodes occurred during the first month. Our data indicate that the application of the calcium antagonist Dil lowered the incidence of posttransplant ATN. In addition, there is a possibility that Dil not only ameliorates ischemic damage in the kidney, but also reduces CS nephrotoxicity.
 ...
PMID:Prevention of posttransplant acute tubular necrosis by the calcium antagonist diltiazem: a prospective randomized study. 331 61

Diuretics have found wide application in critical care medicine. The use of mannitol and loop diuretics in a variety of life-threatening disorders is reviewed. The combined venodilatory and natriuretic effects of bumetanide, furosemide and ethacrynic acid relieve congestive symptoms in pulmonary edema. Although commonly administered to prevent development of acute tubular necrosis or in varying stages of evolving disease, few data are available to demonstrate the efficacy of mannitol or loop diuretics. An approach to the oliguric patient with acute tubular necrosis is described. The dangers of hyponatremia are reviewed, and the rational use of loop diuretics and hypertonic saline is outlined. The 3 loop-active agents inhibit calcium reabsorption in the thick ascending limb of Henle's loop and therefore have proved useful in treating hypercalcemia. A practical approach to the diuretic-saline treatment of severe hypercalcemia is outlined. The kaliuretic effect of loop diuretics can be used to advantage in patients with acute or chronic hyperkalemia. A guide to such therapy is described.
 ...
PMID:Diuretic use in critical care. 351 55

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.
 ...
PMID:Renal response to shock. 377 12


1 2 3 4 5 Next >>