Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0920646 (renal ischemia)
 2,515 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 persisting incidence of acute renal failure has been observed after operative treatment of thoracoabdominal aortic aneurysm, ruptured abdominal aortic aneurysm and renal artery occlusive disease in patients with preoperative impairment of renal function. Because preservation of kidney function can play an important role in the outcome of these patients, the effects of prostaglandin E1 (PGE1) to prevent ischaemic renal failure were studied in an experimental model. Twenty dogs were exposed to 3 h warm ischaemia by clamping of the supra- and infrarenal aorta and both renal arteries. In 10 dogs PGE1 was given intravenously (100 ng/kg/min) for 15 min before clamping. Ten dogs treated with normal saline served as controls. Glomerular filtration rate, renal plasma flow, plasma creatinine, blood urea nitrogen, urine volume, free water clearance and renovascular resistance were calculated before and after renal ischaemia for both groups. The dogs were followed-up for 2 weeks and radionuclide studies with Tc-99m-MAG3, I-131-OIH and In-113m-DTPA were performed on the third postoperative day to calculate global and split renal clearance, tracer extraction fraction and mean transport time. After renal ischemia 9 dogs of the control group and 3 dogs of the PGE1-group developed acute renal failure (P less than 0.05 due to Fisher's exact text). PGE1 infusion significantly attenuated the postischaemic fall in glomerular filtration rate and renal concentrating ability as well as the postischaemic increase of plasma creatinine and blood urea nitrogen induced by 3 h warm renal ischaemia (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Winner of the ESVS Prize 1988. Effects of prostaglandin E1 (PGE1) on experimental renal ischaemia. 265 70

Radionuclide scintigraphy of the renal transplant has assumed an important role in disclosing the complications that beset this life-prolonging procedure. Renal ischemia, whether caused by mechanical obstruction of the blood vessels or ureter or immunological rejection, can be detected by qualitative and quantitative perfusion studies using 99mTc-complexes such as pertechnetate, glucoheptonate and DTPA. Similarly, parenchymal agents such as radiohippurate and 99mTc-DTPA can be quantitated for uptake and their drainage patterns monitored to reveal possible underlying obstructive uropathy and urine extravasation. The literature is replete with mathematical strategems for quantitating perfusion and parenchymal transit of the tracers, but none are truly specific enough to be diagnostic of a given cause of renal ischemia. Serial quantitative radionuclide studies should be obtained during the first 2-3 wk after transplantation with the view of noting an improvement or deterioration of the quantitation parameters as a guage of progress. A deterioration may anticipate biochemical manifestations by 24-48 hr, but it is not specific and must be interpreted in light of the clinical circumstances or necessitate invasive procedures for a definitive diagnosis.
 ...
PMID:Renal transplant evaluation. 676 Apr 1

The potential of using fast magnetic resonance (MR) imaging in conjunction with apnea-induced blood deoxygenation for the noninvasive monitoring of relative perfusion in the rat abdomen has been studied with two experimental models: glycerol-induced focal renal ischemia and transplanted liver tumor. Gradient-echo echo-planar imaging (GRE-EPI) (TE of 20 msec at 2T) of liver and kidney was performed before, during, and after a 60-second apnea episode and then was followed in the same rat by contrast-enhanced (a) GRE-EPI and (b) T1-weighted spin-echo imaging (TR msec/TE msec = 200/6) with polylysine-(gadolinium-DTPA [diethylenetriaminepentaacetic acid]). The results indicate that a noninvasive vascular challenge due to apnea can be used for the detection of focal tissue perfusion abnormalities in rat kidney and liver tumor.
 ...
PMID:MR imaging of blood oxygenation-dependent changes in focal renal ischemia and transplanted liver tumor in rat. 832 7

Based on the previous demonstration of a renoprotective effect of arginine-glycine-aspartic acid (RGD) peptides in acute renal failure, experiments were designed to test the distribution and renal accumulation of the peptide. To accomplish this goal, in this study, RGD peptide was radiolabeled and its biodistribution and renal accumulation was determined in rats with ischemic acute renal failure (ARF). 99mTc-RGD with or without 111In-DTPA were injected intravenously in control and ARF rats. Various organs were dissected at different times after injection and subjected to gamma-scintillation counting and autoradiography (ARG). Blood clearance of 99mTc-RGD was rapid, with t1/2 < 10 min, and unchanged in ARF compared with control rats. Kidneys retained the largest portion of the injected dose in both control and ARF rats, as detected using scintillation counting and whole-body ARG (10.56 +/- 1.05% and 10.12 +/- 3.16% injected dose/g wet weight, respectively). Renal ARG revealed a significant increase in binding to the cortex in ARF kidneys, compared with that of control kidneys. Given the differences in renal blood flow and GFR in control and postischemic kidneys, the next series of experiments was performed with two radiopharmaceuticals, 99mTc-RGD and 111In-DTPA. The ratio of 99mTc-RGD:111In-DTPA was increased more than three-fold in ARF kidneys compared with control kidneys (2.7 +/- 0.15 versus 0.8 +/- 0.19, respectively). The results indicate that (1) RGD peptide undergoes a rapid clearance predominantly via the renal route; (2) despite a significant reduction in the renal perfusion, 99mTc-RGD peptide accumulates in the postischemic kidney; (3) this is consistent with the hypothesis on the involvement of RGD-recognizing integrins in the development of tubular obstruction in renal ischemia.
 ...
PMID:Biodistribution and clearance of 99mTc-labeled Arg-Gly-Asp (RGD) peptide in rats with ischemic acute renal failure. 898 49

Midaortic syndrome (MAS) is a well-recognized but rare cause of renovascular hypertension (RVH). Several techniques have been described to treat RVH caused by MAS. The authors recently treated two children with MAS and RVH. In both patients the right kidney had two renal arteries. A 13-year-old boy presented with severe headaches, pain in his lower extremities with exertion, and marked hypertension (blood pressure, 170/110). An aortogram demonstrated 70% narrowing of his abdominal aorta from the suprarenal region to 5 cm above the iliac bifurcation. There was significant stenosis of the celiac axis, superior mesenteric artery, and left renal artery. The right kidney had two renal arteries, and the upper pole artery was stenotic at its origin. A 10-year-old girl, known to have hypertension for several years had an aortogram that demonstrated 70% narrowing of the abdominal aorta from the suprarenal region to 3 cm above the iliac bifurcation. There was involvement of the left renal artery at its orifice. She also had two renal arteries to the right kidney with the right upper pole artery being stenotic at its origin and in the mid-portion of the vessel. Aortic reconstruction was accomplished with a polytetrafluoroehtylene (PTFE) bypass graft in each case. The first case also involved patch angioplasty of the celiac axis. In both cases, the right kidney was autotransplanted. It was removed intraoperatively, cold perfused, and the two renal arteries reconstructed followed by transplantation to the right iliac vessels. In both cases the left renal artery was reimplanted into the PTFE graft. Both patients had uncomplicated postoperative courses. The 13-year-old boy had evidence of renal ischemia in a portion of the lower pole of the autotransplanted kidney by DTPA scan. He has mild hypertension controlled with antihypertensive medication. The 10-year-old girl has a normal DTPA scan and is normotensive. MAS is a rare and challenging congenital vascular anomaly that causes RVH. In the presence of double renal arteries the technique of autotransplantation with cold perfusion and "bench" vascular reconstruction reduces the warm ischemia time and should produce satisfactory results.
 ...
PMID:Renal autotransplantation for renovascular hypertension caused by midaortic syndrome. 904 31

In 370 patients (pts) with hypertension(HT) in years 1986-1998 (168F + 202M, mean age 46 yrs) screening value of the following tests was evaluated: standard initial angioscintigraphy DTPA 99mTc(SA) in all pts(1-st screening group), significance of clinical suspicion on renovascular hypertension (RVHT) in the group of 74 pts (II-nd screening group). Captopril tests: renin captopril test(RCT) and isotopic captopril test (ICT) were performed in all 370 pts. Classical renal angiography as a reference test for renal artery stenosis (RAS) was performed in all pts suspected for RVHT on the basis of clinical anamnesis and or positive results of captopril tests. Results were as follows. Initial SA being abnormal in the whole group, appeared to be more significant for RAS only in the case of profound one side renal ischemia (GFR lower than 30% of total GFR). Resistance to three antihypertensive drugs, diastolic blood pressure > 120 mmHg and sudden onset of Ht, found in all 74 pts from the II-nd group, were the most significant clinical symptoms of RVHT, because critical RAS was found in 41, that is 55% of pts from the II-nd group. At least one positive CT was found in 37 from 42 pts with critical RAS in angiography with RTC being more sensitive and ICT more specific for hemodynamically significant RAS. The following screening protocol for RVHT was presented and discussed: precise clinical anamnesis followed by angiography or captopril tests according to the severity of clinical symptoms, aim of the study as well as accessibility and laboratory reproducibility of the captopril tests.
 ...
PMID:[Screening for renovascular hypertension in own material (1986-1998)]. 1010 95

This study was designed to determine the possible protective effect of mibefradil on renal ischemia/reperfusion (I/R) injury. Unilaterally nephrectomized Sprague-Dawley rats were subjected to 60 min of left renal ischemia followed by 45 min of reperfusion. Group 1 were sham-operated animals; group 2, I/R/untreated animals; and group III, I/R/mibefradil-treated animals. A 99mTc-DTPA scan was taken to measure kidney perfusion, glomerular filtration rate (GFR) and the time elapsed from isotope injection to the maximum of the curve. Serum creatinine, blood urea nitrogen (BUN), kidney malondialdehyde (MDA) level were determined as well as examining the kidneys histologically. Treatment of rats with mibefradil produced a significant reduction in the serum levels of creatinine and urea nitrogen. T-max-sec (renal perfusion) was significantly lower in group 2 than in groups 1 and 3. The GFR was markedly greater in group 3 than in the group 2. The Tmax-min was significantly greater in group 2 than in group 3. Mibefradil treatment significantly decreased the MDA levels. The histopathologic score was significantly less in the group 3 rats compared with group 2 rats. Kidneys of group 2 rats showed tubular cell swelling, cellular vacuolization, pyknotic nuclei, medullary congestion, and moderate to severe necrosis. Treatment with mibefradil preserved the normal morphology of the kidney and shows normal glomeruli and slight edema of the tubular cells. These findings suggest that mibefradil reduces the renal dysfunction associated with I/R of the kidney.
 ...
PMID:The effects of mibefradil, a T-type Ca2+ channels blocker, on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney. 1635 Aug 33