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1.
JIMD Rep ; 64(6): 410-416, 2023 Nov.
Article En | MEDLINE | ID: mdl-37927490

Lysinuric protein intolerance (LPI), caused by pathogenic variants of SLC7A7, is characterized by protein aversion, failure to thrive, hyperammonemia, and hepatomegaly. Recent studies have reported that LPI can cause multiple organ dysfunctions, including kidney disease, autoimmune deficiency, pulmonary alveolar proteinosis, and osteoporosis. We report the case of a 47-year-old Japanese woman who was initially diagnosed with renal tubular acidosis (RTA), Fanconi syndrome, and rickets. At the age of 3 years, she demonstrated a failure to thrive. Urinary amino acid analysis revealed elevated lysine and arginine levels, which were masked by pan-amino aciduria. She was subsequently diagnosed with rickets at 5 years of age and RTA/Fanconi syndrome at 15 years of age. She was continuously treated with supplementation of vitamin D3, phosphate, and bicarbonate. A renal biopsy at 18 years of age demonstrated diffuse proximal and distal tubular damage with endocytosis-lysosome pathway abnormalities. Distinctive symptoms of LPI, such as protein aversion and postprandial hyperammonemia were not observed throughout the patient's clinical course. The patient underwent a panel-based comprehensive genetic testing and was diagnosed with LPI. As the complications of LPI involve many organs, patients lacking distinctive symptoms may develop various diseases, including RTA/Fanconi syndrome. Our case indicates that proximal and distal tubular damages are notable findings in patients with LPI. The possibility of LPI should be carefully considered in the management of RTA/Fanconi syndrome and/or incomprehensible pathological tubular damage, even in the absence of distinctive symptoms; furthermore, a comprehensive genetic analysis is useful for diagnosing LPI.

2.
Clin Nephrol ; 97(4): 246-251, 2022 Apr.
Article En | MEDLINE | ID: mdl-35102818

Acute renal failure (ARF) with severe loin pain and patchy renal vasoconstriction is a rare syndrome described as an anaerobic exercise-induced acute kidney injury (AKI) without rhabdomyolysis. The characteristic computed tomography (CT) finding is multiple patchy wedge-shaped delayed contrast enhancement in the kidney. The syndrome is named as a clinical syndrome of ARF with severe loin pain after anaerobic exercise (ALPE). A 16-year-old Japanese boy was admitted to our hospital for vomiting and severe loin pain after Japanese fencing. He had kidney dysfunction with slightly increased serum creatine phosphokinase and was eventually diagnosed with ALPE based on the characteristic finding on delayed renal CT scans. He had no predisposing factors for ALPE, such as renal hypouricemia or analgesic use prior to the exercise; however, he had pigmenturia at the onset, which is an unusual finding for ALPE. The pigmenturia proved to be hemoglobinuria due to intravascular hemolysis, indicated by increased serum levels of indirect bilirubin and lactate dehydrogenase, an undetectable level of serum haptoglobin, and absence of red blood cells and myoglobin in the urine. The hemolysis following strenuous steps on a hard floor suggested that the phenomenon was march hemoglobinuria. Our patient is the first reported example in which ALPE developed in the setting of hemoglobinuria due to mechanical intravascular hemolysis.


Acute Kidney Injury , Vasoconstriction , Acute Kidney Injury/diagnosis , Acute Kidney Injury/etiology , Adolescent , Hemoglobinuria , Humans , Kidney , Male , Pain
4.
Breast Cancer (Auckl) ; 11: 1178223417731297, 2017.
Article En | MEDLINE | ID: mdl-28974918

PURPOSE: We evaluated whether the field-in-field (FIF) technique improves the homogeneity of the target in high tangent radiation therapy (HTRT). MATERIALS AND METHODS: This study included 30 patients. In total, 3 HTRT plans were created: 1 with conventional opposed fields (Conv-p), 1 with the FIF technique (FIF-p), and 1 with FIF technique using lung-blocked subfields (FIF-LB-p). RESULTS: The maximum dose of the breast and planning target volume (PTV) was significantly lower for FIF-p and FIF-LB-p than Conv-p. Homogeneity index of PTV was also significantly lower for FIF-p and FIF-LB-p than Conv-p. Homogeneity index of the breast or PTV was significantly better for FIF-p than FIF-LB-p. The volumes of the breast or the PTV receiving 95% and 90% of the prescribed dose were also significantly better for FIF-p, indicating the advantages of FIF-p. CONCLUSIONS: The FIF technique was useful in HTRT and improved homogeneity in the target.

5.
Radiat Oncol J ; 35(1): 71-77, 2017 Mar.
Article En | MEDLINE | ID: mdl-28395503

PURPOSE: Although the technical developments of radiotherapy have been remarkable, there are currently few reports on the treatment results of radiotherapy for local recurrence of rectal cancer treated with surgery alone as initial treatment in this three-dimensional conformal radiotherapy era. Thus, we retrospectively evaluated the treatment results of radiotherapy for local recurrence of rectal cancer treated with surgery alone as the initial treatment. MATERIALS AND METHODS: Thirty-two patients who underwent radiotherapy were enrolled in this study. The dose per fraction was 2.0-3.5 Gy. Because the treatment schedule was variable, the biological effective dose (BED) was calculated. RESULTS: Local control (LC) and overall survival (OS) rates from the completion of radiotherapy were calculated. The 1-, 2-, 3-, 4-, and 5-year LC rates were 51.5%, 24.5%, 19.6%, 19.6%, and 13.1%, respectively. LC rates were significantly higher for the high BED group (≥75 Gy10) than for the lower BED group (<75 Gy10). All patients who reported pain achieved pain relief. The duration of pain relief was significantly higher for the high BED group than for the lower BED group. The 1-, 2-, 3-, 4-, and 5-year OS rates were 82.6%, 56.5%, 45.2%, 38.7%, and 23.2%, respectively. There was a trend toward higher OS rates in with higher BED group compared to lower BED group. CONCLUSION: For patients with unresectable locally recurrent rectal cancer treated with surgery alone, radiotherapy is effective treatment. The prescribed BED should be more than 75 Gy10, if the dose to the organ at risk is within acceptable levels.

6.
Am J Med Genet A ; 170(11): 2889-2894, 2016 11.
Article En | MEDLINE | ID: mdl-27566442

In a clinical setting, the number of organ systems involved is crucial for the differential diagnosis of congenital genetic disorders. When more than one organ system is involved, a syndromic diagnosis is suspected. In this report, we describe three patients with apparently syndromic features. Exome sequencing identified non-syndromic gene mutations as a potential cause of part of their phenotype. The first patient (Patient 1) is a girl with cleft lip/palate, meningoencephalocele, tetralogy of Fallot, and developmental delay. The second and third patients (Patients 2 and 3) are brothers with developmental delay, deafness, and low bone mineral density. Exome sequencing revealed the presence of a CDH1 mutation in Patient 1 and a PLS3 mutation in Patients 2 and 3. CDH1 mutations are known to be associated with non-syndromic cleft lip/palate, while PLS3 mutations are associated with osteoporosis. Thus, these variants may explain a part of the complex phenotype of the patients, although the effects of these missense variants need to be evaluated by functional assays in order to prove pathogenicity. On the basis of these findings, we emphasize the importance of scrutinizing non-syndromic gene mutations even in individuals with apparently syndromic features. © 2016 Wiley Periodicals, Inc.


Exome , Genetic Association Studies , High-Throughput Nucleotide Sequencing , Mutation , Phenotype , Adult , Antigens, CD , Brain/pathology , Cadherins/chemistry , Cadherins/genetics , Child , Computational Biology/methods , DNA Mutational Analysis , Facies , Female , Heterozygote , Humans , Infant , Magnetic Resonance Imaging , Male , Models, Molecular , Protein Conformation , Syndrome
7.
Radiol Med ; 121(4): 323-6, 2016 Apr.
Article En | MEDLINE | ID: mdl-26661953

PURPOSE: In the field-in-field (FIF) technique in breast tangential radiotherapy, the energy of the subfield is usually the same as the energy of the main field. However, some studies have applied 10-18 MV to subfields in patients with large breasts. We compared two FIF plans in 66 breast cancer patients: in one, the energy of the subfield was the same as that of the main field (the mono energy plan); in the other, it was higher (the dual energy plan). MATERIALS AND METHODS: The photon energy of the subfield was 6 MV in the mono energy plan and 10 MV in the dual energy plan. The percentage of the planning target volume (PTV) receiving at least 105, 100, and 95% of the prescribed dose (V105, V100, and V95, respectively) was calculated, as were the maximum and mean doses delivered to the PTV (Dmax and Dmean, respectively). Clinical target volumes (CTVs) and the thickness of the breast between the chest wall and skin surface at the level of the nipple were measured. RESULTS: V95% was significantly higher in the dual energy plan than in the mono energy plan in patients with CTVs or breast thickness in the highest quartile. There were no significant differences in the other parameters of the two plans in these patients. CONCLUSION: These findings demonstrate the usefulness of the dual energy FIF technique in patients with large breasts receiving breast tangential radiotherapy.


Breast Neoplasms/radiotherapy , Female , Humans , Middle Aged , Radiotherapy/methods
8.
Nagoya J Med Sci ; 77(3): 339-45, 2015 Aug.
Article En | MEDLINE | ID: mdl-26412879

Several studies have reported the advantages of the field-in-field (FIF) technique in breast radiotherapy, including dose reduction in the lungs by using lung field blocks. We evaluated the FIF technique with lung blocks for breast tangential radiotherapy. Sixteen patients underwent free breathing (FB) computed tomography (CT), followed by two CT procedures performed during breath hold after light inhalation (IN) and light exhalation (EX). Three radiotherapy plans were created using the FIF technique based on the FB-CT images: one without lung blocks (LB0) and two with lung blocks whose monitor units (MUs) were 5 (LB5) and 10 (LB10), respectively. These plans were copied to the IN-CT and EX-CT images. V20Gy, V30Gy, and V40Gy of the ipsilateral lung and V100%, V95%, and the mean dose (Dmean) to the planning target volume (PTV) were analyzed. The extent of changes in these parameters on the IN-plan and EX-plan compared with the FB-plan was evaluated. V20Gy, V30Gy, and V40Gy were significantly smaller for FB-LB5 and FB-LB10 than for FB-LB0; similar results were obtained for the IN-plan and EX-plan. V100%, V95%, and Dmean were also significant smaller for FB-LB5 and FB-LB10 than for FB-LB0. The extent of changes in V20Gy, V30Gy, and V40Gy on the IN-plan and EX-plan compared with the FB-plan was not statistically significant. Lung blocks were useful for dose reduction in the lung and a simultaneous PTV decrease. This technique should not be applied in the general population.

9.
Radiother Oncol ; 102(2): 198-205, 2012 Feb.
Article En | MEDLINE | ID: mdl-22100656

PURPOSE: To compare the positioning accuracy and stability of two distinct noninvasive immobilization devices, a dedicated (D-) and conventional (C-) mask, and to evaluate the applicability of a 6-degrees-of-freedom (6D) correction, especially to the C-mask, based on our initial experience with cranial stereotactic radiotherapy (SRT) using ExacTrac (ET)/Robotics integrated into the Novalis Tx platform. MATERIALS AND METHODS: The D- and C-masks were the BrainLAB frameless mask system and a general thermoplastic mask used for conventional radiotherapy such as whole brain irradiation, respectively. A total of 148 fractions in 71 patients and 125 fractions in 20 patients were analyzed for the D- and C-masks, respectively. For the C-mask, 3D correction was applied to the initial 10 patients, and thereafter, 6D correction was adopted. The 6D residual errors (REs) in the initial setup, after correction (pre-treatment), and during post-treatment were measured and compared. RESULTS: The D-mask provided no significant benefit for initial setup. The post-treatment median 3D vector displacements (interquatile range) were 0.38 mm (0.22, 0.60) and 0.74 mm (0.49, 1.04) for the D- and C-masks, respectively (p<0.001). The post-treatment maximal translational REs were within 1 mm and 2 mm for the D- and C-masks, respectively, and notably within 1.5 mm for the C-mask with 6D correction. The pre-treatment 3D vector displacements were significantly correlated with those for post-treatment in both masks. CONCLUSIONS: The D-mask confers positional stability acceptable for SRT. For the C-mask, 6D correction is also recommended, and an additional setup margin of 0.5 mm to that for the D-mask would be sufficient. The tolerance levels for the pre-treatment REs should similarly be set as small as possible for both systems.


Cranial Irradiation/instrumentation , Head and Neck Neoplasms/radiotherapy , Immobilization/instrumentation , Masks , Radiotherapy Planning, Computer-Assisted/instrumentation , Robotics/instrumentation , Dose Fractionation, Radiation , Female , Humans , Male , Organs at Risk , Patient Positioning , Statistics, Nonparametric , Stereotaxic Techniques
10.
Nephrol Dial Transplant ; 22(12): 3431-41, 2007 Dec.
Article En | MEDLINE | ID: mdl-17893107

BACKGROUND: In vitro, the extracellular signal-regulated kinase (ERK) is an intracellular convergence point of multiple stimuli, which affect the cell cycle. However, the role of ERK in cell cycle regulation in vivo is unknown. METHODS: To address this issue, ERK activity was blocked both in vitro in mesangial cells (MC) and in vivo in experimental glomerulonephritis (GN) by a pharmacological inhibitor (U0126) of the ERK-activating kinase. RESULTS: In stimulated MC, inhibition of ERK reduced cyclin-dependent kinase 2 (CDK2) phosphorylation, CDK2 activity and cyclin E/A expression, whereas downregulation of CDK inhibitor p27(Kip1) expression was inhibited. In vivo, U0126 was given to rats in the acute phase of anti-Thy 1.1 GN. We previously showed that glomerular cell proliferation was reduced by 67% upon treatment with the inhibitor compared to nephritic controls. Now, we detected a significant increase in renal CDK2-activity/phosphorylation in the nephritic controls, that was significantly and dose-dependently reduced by ERK inhibition. CDK2 activation was accompanied by an increase in renal expression of cyclins E/A and the enhanced binding of these cyclins to CDK2 in the nephritic controls. These changes were blunted by U0126 treatment. Finally, we noted an increased expression and CDK2-binding of p27(KIP1) protein in the nephritic controls which was decreased in U0126 treated rats. CONCLUSIONS: Our observations provide the first evidence that ERK is an intracellular regulator of renal CDK2 activity in vivo in a glomerulonephritis model.


Cyclin-Dependent Kinase 2/metabolism , Extracellular Signal-Regulated MAP Kinases/physiology , Glomerulonephritis/enzymology , Animals , Cells, Cultured , Glomerular Mesangium/cytology , Glomerular Mesangium/metabolism , Male , Rats , Rats, Wistar
11.
J Am Soc Nephrol ; 15(9): 2307-19, 2004 Sep.
Article En | MEDLINE | ID: mdl-15339980

The vascular endothelial growth factor (VEGF) system is of major importance for glomerular endothelial repair in glomerulonephritis (GN) and is significantly affected by nitric oxide (NO) release. For investigating whether glomerular upregulation of inducible NO synthase (iNOS) in GN might affect VEGF-mediated repair, a selective iNOS inhibitor, L-N6-(1-iminoethyl)-lysin (L-NIL), was administered to rats with anti-Thy 1.1 GN from day -2 until day 5 after GN induction. Compared with untreated nephritic rats, L-NIL-treated nephritic rats showed similar mean arterial BP, significantly decreased de novo peak nitrate production, and increased albuminuria on day 6. This was preceded by a significant decrease of glomerular endothelial cell proliferation and endothelial area on day 2 in L-NIL-treated nephritic rats. Upregulation of glomerular VEGF mRNA and protein expression, in particular of the VEGF(164) splicing variant, occurred similarly in L-NIL-treated and untreated nephritic rats on days 2 and 7. However, the upregulation of glomerular VEGF receptor 1 and 2 mRNA expression on day 2 was reduced by 77 and 67%, respectively, in L-NIL-treated nephritic rats as compared with untreated nephritic rats. In parallel, glomerular VEGF(165) binding was reduced by 34% in L-NIL-treated nephritic rats on day 2. Glomerular upregulation of the VEGF(164) co-receptor neuropilin-1 mRNA in nephritic rats was reduced by L-NIL treatment only on day 7. Healthy untreated or L-NIL-treated controls showed no significant differences in any parameter analyzed. In conclusion, impaired repair of glomerular endothelium and downregulation of glomerular VEGF receptor expression was observed after selective iNOS inhibition in experimental GN. These data identify iNOS-derived NO production as the first in vivo regulator of the glomerular VEGF system and as an important mechanism promoting glomerular healing.


Kidney Glomerulus/blood supply , Nitric Oxide Synthase/metabolism , Nitric Oxide/metabolism , Receptors, Vascular Endothelial Growth Factor/physiology , Animals , Neovascularization, Physiologic , Nitric Oxide Synthase/antagonists & inhibitors , Rats , Rats, Inbred Lew , Receptors, Vascular Endothelial Growth Factor/genetics , Up-Regulation
12.
Neural Comput ; 16(1): 99-114, 2004 Jan.
Article En | MEDLINE | ID: mdl-15006025

In order to analyze the stochastic property of multilayered perceptrons or other learning machines, we deal with simpler models and derive the asymptotic distribution of the least-squares estimators of their parameters. In the case where a model is unidentified, we show different results from traditional linear models: the well-known property of asymptotic normality never holds for the estimates of redundant parameters.


Algorithms , Artificial Intelligence , Least-Squares Analysis , Neural Networks, Computer , Linear Models , Reproducibility of Results , Stochastic Processes
13.
J Am Soc Nephrol ; 13(6): 1473-80, 2002 Jun.
Article En | MEDLINE | ID: mdl-12039976

Evidence was recently provided for the activation of extracellular signal-regulated kinase (ERK), the best characterized mitogen-activated protein kinase, as an intracellular convergence point for mitogenic stimuli in animal models of glomerulonephritis (GN). In this study, in vivo ERK activity was blocked, with a pharmacologic inhibitor (U0126) of the ERK-activating kinase, in rats with mesangioproliferative GN. After injection of the monoclonal anti-Thy1.1 antibody (OX-7), the rats were treated (days 3 to 6) with low (10 mg/kg body wt) or high (100 mg/kg body wt) doses of U0126 administered intraperitoneally twice daily. On day 6 after induction of the disease, whole cortical tissue and isolated glomeruli were examined by using kinase activity assays, Western blot analyses, and immunohistochemical assays. Treatment with U0126 significantly reduced glomerular stimulation of ERK in anti-Thy1 GN. In the high dose-treated group, this downregulation was accompanied by a reduction in the number of glomerular mitotic figures, back to healthy control levels, and significant decreases in the numbers of total (P < 0.05) and 5-bromo-2'-deoxyuridine-positive (P < 0.05) glomerular cells. Immunohistochemical double-staining of renal sections demonstrated that mesangial cells were the major glomerular targets of U0126 in anti-Thy1 GN. These observations point to ERK as a putative intracellular mediator of the proliferative response in GN and suggest that pharmacologic treatments that interfere with the activation of ERK may be of potential therapeutic interest.


Glomerulonephritis/etiology , MAP Kinase Signaling System , Animals , Butadienes/pharmacology , Cell Division , Cells, Cultured , Glomerulonephritis/drug therapy , Isoantibodies/immunology , Kidney Glomerulus/pathology , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/physiology , Nitriles/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/physiology , Rats
14.
J Am Soc Nephrol ; 13(5): 1261-1270, 2002 May.
Article En | MEDLINE | ID: mdl-11961014

Selective cyclooxygenase-2 (COX-2) inhibitors have anti-inflammatory activity and reduce proteinuria in experimental membranous glomerulonephritis. Antiangiogenic properties of COX-2 inhibitors were recently reported. Whether these properties are relevant to the glomerular healing process in inflammatory glomerular diseases was investigated. For evaluation of the effects of selective COX-2 inhibitors on the glomerular healing process in a rat model of mesangioproliferative glomerulonephritis (induced by anti-Thy 1.1 antibody), a selective COX-2 inhibitor (rofecoxib or celecoxib) or vehicle was administered daily from day 1 after disease induction until euthanasia on day 6. Additional nephritic rats were treated with rofecoxib or vehicle from day 1 to day 10 and were monitored until day 28. Selective COX-2 inhibition led to significant increases in mesangiolysis (up to +71%) on days 2 and 6 and in albuminuria (up to 3.1-fold) on day 6. This augmentation of glomerular capillary damage was associated with rarefaction of glomerular endothelial cells, whereas the proliferation and activation of mesangial cells were not affected. No significant effects on the glomerular influx of polymorphonuclear neutrophils or the infiltration and proliferation of monocytes/macrophages at day 2 were noted. These effects were independent of systemic hemodynamic features, because rofecoxib did not affect systolic BP on day 2 or 5. Nephritic rats treated with rofecoxib for 10 d demonstrated persistent glomerular injury at day 28, as indicated by increased albuminuria (10-fold) and mesangial type IV collagen deposition (+24%). In normal rats, 5-d administration of rofecoxib failed to induce albuminuria or morphologic renal damage. In conclusion, selective COX-2 inhibitors impair glomerular capillary repair after mesangiolysis in rats with anti-Thy 1.1 glomerulonephritis. These data suggest that selective COX-2 inhibitors should be used with caution among patients with inflammatory endocapillary glomerular disorders.


Cyclooxygenase Inhibitors/toxicity , Glomerular Mesangium/drug effects , Glomerulonephritis, Membranoproliferative/metabolism , Glomerulonephritis, Membranoproliferative/physiopathology , Lactones/toxicity , Sulfonamides/toxicity , Animals , Celecoxib , Cyclooxygenase Inhibitors/pharmacology , Glomerular Mesangium/blood supply , Glomerular Mesangium/metabolism , Hemodynamics/drug effects , Immunoenzyme Techniques , Lactones/pharmacology , Microscopy, Electron , Pyrazoles , Rats , Statistics, Nonparametric , Sulfonamides/pharmacology , Sulfones
15.
J Am Soc Nephrol ; 13(4): 910-917, 2002 Apr.
Article En | MEDLINE | ID: mdl-11912250

Platelet-derived growth factor-C (PDGF-C) is a new member of the PDGF family. Its expression in normal and diseased kidney is unknown. Rabbit antisera were generated against human full-length, core domain, and mouse PDGF-C, and their specificity was confirmed by Western blot analyses. Renal PDGF-C expression was analyzed by immunohistochemistry in normal rats (n = 8), mesangioproliferative anti-Thy 1.1 nephritis (n = 4 each at days 1, 4, 6, and 85), passive Heymann nephritis (PHN, n = 4), puromycin nephrosis (PAN, n = 2), Milan normotensive rats (MN, n = 2), and obese Zucker rats (n = 3). PDGF-C expression was also studied in anti-Thy 1.1 rats treated with PDGF-B aptamer antagonists (n = 5) or irrelevant control aptamers (n = 5). PDGF-C was constitutively expressed in arterial smooth muscle cells and collecting duct epithelial cells. Mesangial PDGF-C was markedly upregulated in anti-Thy 1.1 nephritis in parallel with the peak mesangial cell proliferation. Furthermore, PDGF-CC acted as a potent growth factor for mesangial cells in vitro. Inhibition of PDGF-B via specific aptamers reduced the injury in anti-Thy 1.1 nephritis but did not affect the glomerular PDGF-C overexpression or the mitogenicity of PDGF-CC in vitro. In PHN, PAN, and obese Zucker rats, glomeruli remained negative for PDGF-C despite severe glomerular injury. PDGF-C localized to podocytes at sites of focal and segmental sclerosis in MN. Interstitial PDGF-C expression was increased at sites of fibrosing injury in obese Zucker rats. The use of the different antisera resulted in virtually identical findings. It is concluded that PDGF-C is a novel mesangial cell mitogen that is constitutively expressed in the kidney and specifically upregulated in mesangial, visceral epithelial, and interstitial cells after predominant injury to these cells. PDGF-C may therefore be involved in the pathogenesis of renal scarring.


Kidney Diseases/metabolism , Kidney/metabolism , Platelet-Derived Growth Factor/metabolism , Animals , Cell Division/drug effects , Fibrosis , Glomerular Mesangium/cytology , Glomerulonephritis, Membranoproliferative/metabolism , Growth Substances/pharmacology , In Vitro Techniques , Kidney Diseases/pathology , Kidney Glomerulus/pathology , Kidney Tubules/pathology , Lymphokines , Male , Platelet-Derived Growth Factor/pharmacology , Proto-Oncogene Proteins c-sis/physiology , Rats , Rats, Inbred Strains , Reference Values
16.
Kidney Int ; 61(3): 834-8, 2002 Mar.
Article En | MEDLINE | ID: mdl-11849434

BACKGROUND: A particular Lewis rat substrain (LEW/Maa) develops chronic glomerulonephritis in the anti-Thy 1 model (aThy 1-GN) characterized by increased microaneurysm formation, chronic glomerular sclerosis and persistent albuminuria. This phenotype is accompanied by increased and prolonged glomerular induction of inducible nitric oxide synthase (iNOS) when compared to the LEW/Moe substrain, in which aThy 1-GN resolves quickly. We investigated the effect of selective iNOS inhibition by l-N6-(1-iminoethyl)-lysine (L-NIL) administration on aThy 1-GN in LEW/Maa rats. METHODS: Nephritic rats were studied over a period of 7 days. L-NIL-treated animals received 20 mg/day L-NIL in the drinking water starting two days prior to disease induction. iNOS activity was determined in cultured glomeruli and in urine samples, respectively. Severity of aThy 1-GN was determined by scoring glomerular matrix expansion and microaneurysm formation, and by albuminuria measurements (ELISA). Immunohistochemical evaluation was performed including staining for macrophages (ED-1), platelets (PL-1) and fibrin deposition. RESULTS: L-NIL treated rats (+NIL) showed a significant decrease in peak nitrate production by ex vivo cultured glomeruli, and in urinary nitrate excretion versus untreated nephritic rats (-NIL). Mean arterial pressure remained unchanged in both +NIL and -NIL rats. +NIL rats developed significantly increased albuminuria (+44%) associated with a significant increase in glomerular platelet (+45%) and fibrin deposition (+48%). CONCLUSIONS: Selective inhibition of iNOS aggravated albuminuria in chronic aThy 1-GN in LEW/Maa rats. Induction of iNOS during the inflammatory phase of this model may be a partially protective mechanism by interfering with intraglomerular coagulation processes.


Enzyme Inhibitors/pharmacology , Isoantibodies/immunology , Kidney Glomerulus/blood supply , Kidney Glomerulus/physiopathology , Lysine/analogs & derivatives , Lysine/pharmacology , Nephritis/immunology , Nephritis/physiopathology , Nitric Oxide Synthase/antagonists & inhibitors , Thrombosis/pathology , Albuminuria/urine , Animals , Blood Platelets/pathology , Blood Pressure/drug effects , Chronic Disease , Fibrin/metabolism , Nephritis/complications , Nephritis/urine , Nitric Oxide Synthase Type II , Rats , Rats, Inbred Lew , Thrombosis/etiology
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