Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Nephrectomy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,567 records · Page 87Linked to original sources
PubMed1990

Effects of a Japanese medicinal plant on the rat subtotal nephrectomy model: evaluation of its effect by microvascular casts.

Effects of a Japanese medicinal plant named Sairei-To, were examined in a rat experimental renal disease. Thirteen weeks after subtotal nephrectomy, the blood pressures in rats given Sairei-To (Sairei-To rats) were lower than those without Sairei-To. The urinary protein excretions and glomerular sclerosis were markedly decreased in the Sairei-To treated rats. Arteriolar diameters were measured using microvascular casts. The afferent and efferent arterioles were both significantly dilatated. The efferent arterioles in Sairei-To rats were dilated to a greater extent than that of the afferent. These results indicated that Sairei-To lessened renal damages in the rat subtotal nephrectomy model, possibly through the blood pressure reduction and the efferent arteriolar dilatation.

Animals↗
PubMed1979

Computed tomography of the retroperitoneum following nephrectomy.

Twenty-five patients were examined by computed tomography (CT) after nephrectomy. CT was useful in the detection of postoperative complications and local recurrence of tumor. Ultrasound was difficult because of rib artifacts or bowel gas, and a fluid-filled bowel often simulated tumor: oral contrast material was useful during CT. Local recurrence was demonstrated by CT in 8 patients in whom it was clinically suspected. Recurrent tumor was simulated by scarring in 3 cases and by an accessory or residual spleen in 2. Operative complications included one hematoma and one retroperitoneal abscess. CT could be useful in following up selected patients after nephrectomy.

Adult↗
PubMedDate not supplied

Role of CT angiography in the preoperative evaluation for laparoscopic nephrectomy.

Laparoscopic nephrectomy (LN) was recently introduced as a minimally invasive alternative to open nephrectomy in living related renal donation. Because of the limited field of view available with laparoscopic techniques, the role of preoperative radiologic evaluation in LN has expanded to include anatomic definition of the renal arteries, collecting system, renal parenchyma, and renal venous anatomy. Computed tomographic (CT) angiography has proved to be a minimally invasive alternative to conventional angiography in the preoperative evaluation of living related renal donors. CT angiography has been shown to have an accuracy comparable to that of conventional angiography in predicting renal arterial anatomy. In addition, CT angiography provides comprehensive definition of the renal vascular anatomy including the location, size, and length of the renal, adrenal, gonadal, and lumbar veins. Dual-phase spiral CT combined with three-dimensional CT angiography constitute a single, minimally invasive procedure that can provide a complete preoperative evaluation of potential living related renal donors prior to LN. Comprehensive anatomic depiction of the renal arterial and venous supplies aids in surgical planning and helps avoid potential complications.

Adult↗
PubMedDate not supplied

Multi-detector row CT evaluation of living renal donors prior to laparoscopic nephrectomy.

Since its introduction in 1995, laparoscopic nephrectomy has become the preferred technique at many medical centers for the harvesting of kidneys from living donors for transplantation. Because the field of view at laparoscopic surgery is limited, preoperative radiologic evaluation of the donor's anatomy---the renal veins and arteries, collecting system, and parenchyma--is critical. Spiral computed tomographic (CT) angiography is a fast, safe, minimally invasive, and generally accepted method for preoperative evaluation of the renal vessels. Multi-detector row CT scanners offer shorter image acquisition time, narrower collimation, better spatial resolution, and less tube heating than do single-detector row CT scanners. Multi-row scanners also provide more complete anatomic coverage, increased contrast enhancement of the arteries, and greater longitudinal spatial resolution--all of which are important both for accurate imaging of the renal vasculature and for three-dimensional postprocessing of image data. Dual-phase multi-detector row CT angiography combined with three-dimensional postprocessing enables minimally invasive and highly accurate depiction of the preoperative donor anatomy. To make the most effective use of this method, radiologists must be familiar with its technical aspects, advantages, and potential pitfalls. They also must be able to identify variations in vasculature and in renal and extrarenal anatomy that are important for laparoscopic donor nephrectomy.

Equipment Design↗
PubMed1999

Unilateral nephrectomy in the rat as a teaching model of renal function.

The white rat offers a valuable teaching model to demonstrate the in situ anatomy, homeostatic control, and function of the mammalian renal system. Students in the upper-level physiology class at Dickinson College are responsible for formulating a set of testable hypotheses as to the possible compensatory mechanisms that will result from a unilateral nephrectomy in the rat. To test their hypotheses, each group of students is made responsible for induction and maintenance of anesthesia, removal of the left kidney, closure, and recovery of the animal in their experiment. Before and 1 wk after nephrectomy, blood samples are collected via tail section for measurement of hematocrit and plasma creatinine concentrations. Pooling data across all student groups (n = 6) for pre- and postnephrectomy hematocrit and creatinine values allows students to run statistical comparisons testing their hypotheses. This laboratory experience in integrative physiology is a successful exercise in introducing fundamentals of experimental design and, most importantly, provides students with an appreciation for the process of humane use of animals in research and teaching.

Animals↗
PubMed1982

Hemodynamic and renal functional changes after acute unilateral nephrectomy in the dog: role of carotid sinus baroreceptors.

We examined the role of the carotid sinus baroreceptors in the hemodynamic and renal functional changes initiated by acute unilateral nephrectomy (AUN). In 15 anesthetized dogs, AUN caused increases in sodium (UNaV) and potassium excretion (UKV) without significant changes in GFR, renal blood flow, or mean arterial pressure. Cardiac output (CO) was measured in five of these animals and decreased from 2.5 +/- 0.2 to 1.9 +/- 0.3 liter/min as total peripheral resistance (TPR) increased. In 11 dogs with bilateral acute surgical carotid sinus denervation, AUN failed to cause any change in renal hemodynamics, UNaV, or UKV that could be distinguished from sham-operated time controls. CO was measured in seven of these dogs and also did not change. AUN caused an immediate, transient elevation in blood pressure that returned to control levels 15 min after nephrectomy. When bilateral carotid occlusion (BCO) was carried out prior to AUN in animals with intact carotid sinus baroreceptors, AUN again caused an immediate increase in blood pressure but no changes in CO or electrolyte excretion. In separate studies, AUN increased UNaV and UKV significantly; when BCO was then carried out after AUN, cation excretion remained elevated. In seven dogs undergoing continuous perfusion of the carotid circulation bilaterally at constant pressure, AUN again failed to increase cation excretion despite a 30 mmHg rise in arterial blood pressure. These studies demonstrate that AUN fails to initiate hemodynamic or compensatory renal functional changes in dogs with bilateral carotid sinus denervation or in animals in which intact baroreceptors are shielded from the systemic circulation by BCO or perfusion at constant pressure, indicating the importance of these baroreceptors in the early changes after AUN.

Afferent Pathways↗
PubMed1992

Cellular morphology in outer medullary collecting duct: effect of 75% nephrectomy and K+ depletion.

The present study was designed to determine, in rats, whether 75% nephrectomy and potassium depletion affect the principal and intercalated cells in the outer medullary collecting duct in the same manner as they affect the principal and intercalated cells in the cortical collecting duct. Ten days after a 75% reduction of renal mass, whole animal glomerular filtration rate decreased and the fractional excretion of potassium increased in rats. However, no morphological changes occurred in either the principal or intercalated cells of the outer medullary collecting duct after the reduction of renal mass. When 75% nephrectomized rats were placed on a diet deficient in potassium, the concentration of potassium in plasma and the absolute and fractional excretion of potassium decreased significantly. In addition, marked hypertrophy occurred in both the principal and intercalated cells in the outer medullary collecting duct. Previous findings from the same animals used in the present study show that 75% nephrectomy caused hypertrophic changes in principal cells of the cortical collecting duct, which could be inhibited by potassium depletion induced by the dietary restriction of potassium. The findings also show that the intercalated cells of the cortical collecting duct in 75% nephrectomized rats were unaffected by potassium depletion. On the basis of our findings, it appears there is an absence of hypertrophy in either the principal or intercalated cells in the outer medullary collecting duct of the rat after renal mass in the animal is reduced significantly.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Early increase in pulsatile growth hormone release after unilateral nephrectomy in adult rats.

Removal of one kidney results, within days, in accelerated growth of the remaining kidney. However, the mechanisms that underlie this compensatory renal hypertrophic response, particularly in the early time period following nephrectomy, are not understood. In this study we tested the hypothesis that removal of one kidney leads to a change in the pulsatile release of growth hormone (GH), which facilitates compensatory renal growth. Adult Wistar rats were implanted with Silastic cannulas in jugular veins and underwent either unilateral nephrectomy (UNX) or sham operation. Plasma levels of GH were determined 24 and 48 h after sham operation or UNX. Blood samples were taken every 20 min over a 6-h period from conscious, unrestrained animals. Pulsatile GH release was markedly elevated 24 h after UNX in both the amplitude of the surges as well as in the duration of release. Peak GH levels after 24 h were three- to fourfold higher in UNX rats compared with sham controls (417 +/- 75 vs. 119 +/- 23 ng/ml, P < 0.05). However, this enhanced release of GH appeared to be of short duration and began declining by 48 h post-UNX (peak level of 227 +/- 37 ng/ml, P < 0.05 vs. both 24 h UNX and sham controls). To examine whether this rise in GH release post-UNX contributed to the compensatory renal growth, rats underwent UNX and were immediately treated with an antagonist to GH-releasing factor (GRF-AN; i.e., [N-Ac-Tyr1,D-Arg2]GRF-(1-29) amide, 200 micrograms/kg twice daily), and the effects on GH release and renal growth were determined. Administration of GRF-AN significantly suppressed the increase in GH release post-UNX and was associated with a significant attenuation in renal growth 48 h post-UNX in GRF-AN-treated rats (8.7 +/- 2.6% vs. 22.7 +/- 3.0% in UNX controls, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed1995

Subtotal but not unilateral nephrectomy induces hyperplasia and protooncogene expression.

It is generally accepted that renal compensatory growth after unilateral nephrectomy (Uni) is due to prominent hypertrophy with no involvement of protooncogenes. Neither the balance between hypertrophy and hyperplasia nor the expression of the early-growth-related genes has been studied after subtotal nephrectomy (Nx). The occurrence of cystic tubular dilatations after Nx may suggest an excessive cell proliferation in this model. We measured DNA, RNA, and protein content, number of nuclei per tubular section, as well as c-fos, c-jun, c-myc, c-H-ras, c-sis, and c-erb-B2 protooncogene expression in kidneys taken at time of surgery and 2, 7, and 14 days after sham operation (control rats), Uni, or Nx. After Uni, hyperplasia was greater than expected (+79% for DNA at day 14) and was associated with moderate hypertrophy (+11% for protein/DNA ratio). After Nx, compensatory growth was due only to hyperplasia (+117% for DNA at day 14), with unchanged protein/DNA ratio (vs. Uni, P < 0.02). The greater hyperplasia after Nx was confirmed by nuclei counting. The protooncogene mRNA expression was constantly absent in control and Uni rats, whereas that of c-fos and c-jun genes was detected in Nx rats at day 14 with a 2- to 12-fold increment. The c-fos and c-jun protein levels were also increased at that time in Nx rats. This suggests the following: 1) the cellular events following Uni and Nx are not the same, and 2) the late protooncogene expression in Nx exclusively could favor a particular type of cell proliferation possibly more related with cystic formation than with actual compensatory growth.

Adaptation, Physiological↗
PubMed1996

Na-K-ATPase along rat nephron after subtotal nephrectomy: effect of enalapril.

Tubular overwork is thought to be a promoter of the tubular hypertrophy and renal failure that occur in response to renal mass reduction. Because Na-K-adenosinetriphosphatase (Na-K-ATPase) is an index of tubular work, we evaluated the effects of subtotal nephrectomy and of enalapril therapy, which delays the evolution of renal lesions, on tubular hypertrophy and Na-K-ATPase activity along the rat nephron. Within 6 wk, 70% reduction of renal mass engendered hypertrophy of the proximal convoluted tubule (PCT), thick ascending limb (TAL), and collecting duct (CD), as well as parallel increments in Na-K-ATPase activity per millimeter tubule length (Na-K-ATPase activity per unit surface area was not modified by subtotal nephrectomy). Chronic enalapril therapy prevented part of the hypertrophy (but not Na-K-ATPase stimulation) of the PCT and the whole stimulation of Na-K-ATPase (but not hypertrophy) in the CD, whereas it had no effect on the TAL. Enalapril effect on Na-K-ATPase in CD might result from reduced bradykinin metabolism, as the reduction in urinary excretion of bradykinin observed in subtotally nephrectomized rats was prevented by enalapril therapy.

Aldosterone↗
PubMed2005

Ozone therapy on rats submitted to subtotal nephrectomy: role of antioxidant system.

Chronic renal failure (CRF) represents a world health problem. Ozone increases the endogenous antioxidant defense system, preserving the cell redox state. The aim of this study is to evaluate the effect of ozone/oxygen mixture in the renal function, morphology, and biochemical parameters, in an experimental model of CRF (subtotal nephrectomy). Ozone/oxygen mixture was applied daily, by rectal insufflation (0.5 mg/kg) for 15 sessions after the nephrectomy. Renal function was evaluated, as well as different biochemical parameters, at the beginning and at the end of the study (10 weeks). Renal plasmatic flow (RPF), glomerular filtration rate (GFR), the urine excretion index, and the sodium and potassium excretions (as a measurement of tubular function) in the ozone group were similar to those in Sham group. Nevertheless, nephrectomized rats without ozone (positive control group) showed the lowest RPF, GFR, and urine excretion figures, as well as tubular function. Animals treated with ozone showed systolic arterial pressure (SAP) figures lower than those in the positive control group, but higher values compared to Sham group. Serum creatinine values and protein excretion in 24 hours in the ozone group were decreased compared with nephrectomized rats, but were still higher than normal values. Histological study demonstrated that animals treated with ozone showed less number of lesions in comparison with nephrectomized rats. Thiobarbituric acid reactive substances were significantly increased in nephrectomized and ozone-treated nephrectomized rats in comparison with Sham group. In the positive control group, superoxide dismutase (SOD) and catalase (CAT) showed the lowest figures in comparison with the other groups. However, ozone/oxygen mixture induced a significant stimulation in the enzymatic activity of CAT, SOD, and glutathione peroxidase, as well as reduced glutathione in relation with Sham and positive control groups. In this animal model of CRF, ozone rectal administrations produced a delay in the advance of the disease, protecting the kidneys against vascular, hemorheological, and oxidative mechanisms. This behavior suggests ozone therapy has a protective effect on renal tissue by downregulation of the oxidative stress shown in CRF.

Animals↗
PubMed2000

Paramedian extraperitoneal approach for combined nephrectomy and augmentation ureterocystoplasty in children with neurovesical dysfunction.

OBJECTIVES: We describe and evaluate our approach to combined nephrectomy and augmentation ureterocystoplasty using a single paramedian extraperitoneal incision. PATIENTS AND METHODS: Three patients with neurogenic bladders (2 posterior urethral valves and 1 myelodysplasia) underwent nephrectomy and augmentation ureterocystoplasty. The mean age of the patients was 4.6+/-1.5 years. The indications for the procedure included control of urinary incontinence or preservation and stabilization of renal function. RESULTS: The integrity of the peritoneal cavity was easily preserved throughout the procedure using a paramedian incision. No complications were encountered in these patients. Early postoperative resumption of normal diet and activity was noted in all patients. CONCLUSION: The paramedian extraperitoneal approach through a single incision provides the advantages seen with other extraperitoneal techniques combining two incisions. The single paramedian incision has the potential to save on operative time and obviates the need to change the patient's position on the operating table while under anesthesia. Furthermore, the paramedian extraperitoneal approach provides the reconstructive surgeon with the chance to convert the procedure into a transperitoneal technique to incorporate bowel segments in order to complement ureterocystoplasty.

Child↗
PubMedDate not supplied

Beneficial effect of the long-term treatment with the combination of an ACE inhibitor and a calcium channel blocker on renal injury in rats with 5/6 nephrectomy.

The effects of the addition of a calcium channel blocker, verapamil (20 mg/kg/day) to an ACE inhibitor, trandolapril (0.7 mg/kg/day) in a 6-month treatment on renal insufficiency development in rats with 5/6th nephrectomy, were studied. Every month we measured heart rate and arterial pressure by the tail-cuff method. Renal function studies were performed in metabolic cages. At the end of the study, renal tissue was prepared for light microscope analysis. Renal lesions were assessed by semiquantitative scores in a blind fashion. Corpuscular section area, intraglomerular and tubulointerstitial fibrosis were determined by digital image analysis with a specific software (Fibrosis HR) on syrium red-stained renal sections. Trandolapril markedly increased the survival ratio that after 6 months reached 87% in comparison with 61% in untreated rats. No mortality was observed in rats treated with the combination of verapamil and trandolapril. Trandolapril treatment prevented the development of hypertension. The combination verapamil-trandolapril did not induce further reduction on blood pressure. The untreated group showed a marked proteinuria, that in the trandolapril group showed an important reduction. The verapamil + trandolapril group showed a proteinuria significantly smaller than that of all the other groups. Light microscopy semiquantitative studies of the renal injury showed that the trandolapril and verapamil + trandolapril groups had a marked reduction in glomerular and tubulointerstitial alterations, compared with untreated animals. Quantitative determinations of glomerular and interstitial fibrosis performed on syrium red-stained renal sections demonstrated that fibrosis was reduced when rats when treated with trandolapril and even more with verapamil + trandolapril when they were compared to untreated animals' values. In conclusion, long-term treatment with verapamil given in addition to trandolapril produces additional protection against progressive renal injury associated to subtotal nephrectomy.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1998

Differential effect of nephrectomy on renal expressions of IGF-I and IGFBPs mRNA in selective growth hormone-deficient rats.

It is known that growth hormone (GH) contributes to glomerulosclerosis and that this probably occurs via insulin-like growth factor-I (IGF-I). However, the manner by which GH and nephrectomy (Nx) alter IGF-binding protein (IGFBP) mRNA in the kidney has not been fully explained. The effects of GH on renal IGF-I and IGFBP-1, 2, 3, 4, and 5 following Nx were examined in spontaneous dwarf rats (SDRs) which have a complete and specific lack of GH among pituitary hormones. In normal Sprague-Dawley rats (SDs), Nx resulted in significant decreases in levels of IGFBP-1 mRNA and IGFBP-5 mRNA to 62.7 +/- 4.9 and 56.5 +/- 5.0% those of sham-operated kidneys, respectively. Nx did not alter the IGF-I mRNA level in SDs. The levels of IGFBP-2, IGFBP-3, and IGFBP-4 mRNAs were likewise unchanged following nephrectomy. In SDRs, Nx significantly decreased the levels of IGFBP-1, IGFBP-4, and IGFBP-5 mRNA, to 57 +/- 2.6, 46 +/- 12, and 64 +/- 8.1% of sham-operated animals. However, Nx did not alter the levels of IGF-I, IGFBP-2, and IGFBP-3 mRNA. GH injections of nephrectomized SDRs fully normalized the decreased IGFBP-4 mRNA levels, whereas levels of IGFBP-1 and IGFBP-5 mRNA were not reversed. The altered expression of IGFBP-4 mRNA following Nx of SDRs compared to that of SDs appears highly significant since it is known that, unlike SDs, glomerulosclerosis does not fully develop in SDRs following renal ablation. The change in the IGFBP-4 mRNA level might be related to the development of glomerulosclerosis in SDs.

Animals↗
PubMed2002

Recurrence of renal cell carcinoma with extensive vena caval thrombus three years after radical nephrectomy.

A 70-year-old man, who had undergone a radical nephrectomy for localized renal cell carcinoma (RCC) three years ago, was recently evaluated for shortness of breath. During his work-up, a transesophageal echocardiogram and magnetic resonance imaging indicated an extensive vena caval thrombus originating from the renal vein stump. Successful vena caval thrombectomy with cardiopulmonary bypass confirmed that the thrombus was comprised of RCC. This is a rare type of RCC recurrence with an unusual timing (3 years after a nephrectomy), alerting the importance of strict follow-up on all patients even after complete surgical excision of all suspected tumors.

Aged↗
PubMed1982

Functional compensatory changes after unilateral nephrectomy in rats. General and intrarenal hemodynamic alterations.

Cardiac output (CO), total peripheral resistance (TPR), renal blood flow (RBF), renal vascular resistance (RVR) and intrarenal blood flow distribution have been measured 48 h after unilateral (right) nephrectomy (UNX) and in sham-operated rats (SO). Glomerular filtration rate (GFR) and renal plasma flow (RPF) were determined using standard inulin and PAH clearances. Superficial single nephron GFR (SNGFR) was measured by free-flow micropuncture techniques. Extracellular fluid volume (ECV) and plasma volume (PV) were also determined. UNX rats showed increases of 17.4% in remnant kidney GFR and 34.5% in RPF. Filtration fraction was decreased to 0.27 +/- 0.01 (control value 0.31 +/- 0.01; p less than 0.0025). SNGFR was 45% higher in UNX rats and the ratio SNGFR/GFR increased by 28%. Cardiac output also increased (33.6 +/- 1.0 for UNX rats; 28.0 +/- 1.2 ml/min/100 g BW for SO rats; p less than 0.0025) accompanied by a corresponding fall (20%) in TPR. Left kidney RBF increased by 22%, whereas RVR decreased by 21%. Blood flow through individual glomeruli increased in the outer and inner cortex and was unchanged in the midcortex. In conclusion, 48 h after unilateral nephrectomy, rats showed a hyperdynamic circulatory state with increased CO and decreased TPR; this could be involved in the acute adaptive functional and renal changes reported after uninephrectomy.

Animals↗
PubMedDate not supplied

Effect of subtotal nephrectomy on the excretion of urinary alanine aminopeptidase and gamma glutamyltransferase in the male Wistar rat. A long-term study.

The study of alanine aminopeptidase (AAP) and gamma glutamyltransferase (GGT), two integral components of the brush border membrane of the proximal kidney tubule, has generated considerable interest for research on the nephrotoxicity of drugs. AAP and GGT activity in urine correlate strongly. The three phases after a subtotal nephrectomy can be described as follows: the first phase, lasting 1 month, is characterized by an abrupt decrease of 70% in AAP and GGT activity, corresponding to the excised kidney mass. During the second phase, a partial recovery occurs representing nearly 50% of the AAP and GGT activity in the control group (30th to the 75th day after nephrectomy). These activities begin to decrease slightly in the third phase until the end of the experiment. In terms of remaining kidney mass, the results demonstrate a twofold increase of the AAP and GGT activity. The same phenomenon can be seen in the excretion of creatinine, except that the compensatory activity is multiplied by four in the remaining kidney. Good correlations between AAP activity, GGT activity, urinary creatinine, 24-hour urine volume, and 24-hour creatinine output are found in both experimental and control groups.

Aminopeptidases↗
PubMed1986

Unstimulated renal venous renin ratio predicts improvement in hypertension following nephrectomy for unilateral renal disease.

The ability of renal venous renin ratio (RVRR) to predict the blood pressure response to nephrectomy was studied in 45 hypertensive patients followed for at least 1 year after nephrectomy. Twenty patients had unilateral chronic parenchymal renal disease (UCPR) and 25 patients had unilateral renal artery stenosis (RAS). The RVRR procedure was performed according to a strict protocol which included sodium restricted diet (40 mmol daily) and hospital admission, with one set of unstimulated samples collected after overnight recumbency, and at least one further set collected after sympathetic nervous system stimulation induced by tilting or i.v. diazoxide. In only 3 of 12 patients with serum creatinine 0.15 mmol/l or higher and presumed bilateral renal disease was hypertension improved. If these 12 patients are excluded, RVRR was a good predictor of outcome, but only if the question of unstimulated and stimulated ratios was considered. Whereas inclusion of stimulated ratios increased the predictive accuracy to 81% in RAS, and avoided two false-negatives, in UCPR the stimulated ratio created four false-positives. Since there were no false-negatives and six true-negatives in UCPR, overnight recumbent RVRR was a perfect predictor of outcome in this sub-group. It appears that RVRR without sympathetic stimulation is most reliable in UCPR, and RVRR during sympathetic stimulation in RAS, raising the question that renin regulation may be different in these two conditions.

Adolescent↗