No abstract available.
Animals ; Glomerulosclerosis, Focal Segmental* ; Lovastatin* ; Puromycin* ; Rats*

Hyalinizing trabecular adenoma is an uncommon benign thyroid tumor that is recently described in the literature. This tumor is easily confused with medullary carcinoma on surgical specimens and with papillay carcinoma on cytologic specimens. Herein we report the cytologic characteristics of a case of histologically proven hyalinizing trabecular adenoma of the thyroid gland. Cytologically, the aspirate showed trabecular or individually dispersed polygonal cells with finely stippled chromatin pattern, nuclear grooves, and eosinophilic nuclear pseudoinclusions. No colloid materials were noted in the background.
Adenoma ; Animals ; Carcinoma, Medullary ; Chromatin ; Colloids ; Eosinophils ; Hyalin ; Mediastinum ; Puromycin Aminonucleoside* ; Puromycin* ; Rats* ; Thyroid Gland

PURPOSE: The aim of this study is to investigate the effect of glomerular cyclooxygenase-2 (COX-2) overexpression on podocyte injury by puromycin aminonucleoside (PAN) in nephrin-driven COX-2 transgenic mice. METHODS: We administrated PAN intravenously on day-1 (15 mg/100 g body weight) and day-3 (30 mg/100 g body weight) in wild type (male B6/D2 mice) and COX-2 transgenic mice. An additional group received a selective COX-2 inhibitor (SC58236) with PAN. The animals from each group were sacrificed at the end of day-3 and 10. We investigated albuminuria, foot process effacement and glomerular COX-2 and nephrin expression. RESULTS: PAN induced albuminuria only in COX-2 transgenic mice, with the peak on day-3. Selective COX-2 inhibition significantly reduced albuminuria. EM examination demonstrated foot process effacement, which was improved partially by selective COX-2 inhibition, in COX-2 transgenic mice treated with PAN on day-3. Glomerular COX-2 expression increased significantly on day-3 in COX-2 transgenic mice treated with PAN, whereas expression of nephrin showed a tendency to decrease on day-3. These changes of expression of COX-2 and nephrin were partly attenuated by selective COX- 2 inhibition. Unlike COX-2 transgenic mice, wild-type mice did not show any changes even after PAN treatment. CONCLUSION: In COX-2 transgenic mice, PAN induced albuminuria, podocyte injury and up-regulation of glomerular COX-2, which were ameliorated by selective COX-2 inhibitor. These results suggest that COX-2 may play an important role in increasing susceptibility of podocytes to injury and selective COX-2 inhibition may ameliorate podocyte injury.
Albuminuria ; Animals ; Cyclooxygenase 2* ; Foot ; Mice* ; Mice, Transgenic ; Podocytes* ; Puromycin Aminonucleoside ; Puromycin* ; Up-Regulation

In vitro PVR(Proliferative vitreoretinopathy) models allow identification of factor which may inhibit porliferation and contraction. In this study we evaluated the contraction of collagen matrix by choroidal fibroblast and the inhibition of contraction by antipoliferative drug. Each antiproliferative drug showed inhibition of collagen matrix contraction : Colchicine (0.1microgram/ml), Cytochalacin (0.05microgram/ml), Puromycin(10microgram/ml). Transmission electron microgram of collagen matrices containing colchicine, cytochalacin or puromycin showed no collagen fiber surrounding choroid fibroblast and showed cell destruction. Scanning electron microgram of collagen matrices containing colchicine, cytochalacin and puromycin showed that collagen fibers were well preserved without distortion. Colchicine, cytochalacin and puromycin are effective inhibitor of cell mediated contraction in additon to it`s potent antiproliferative effect wherease Interfereon has no anticontractile effect. The current study present a model to investigate the effect of antiproliferative drug on fibroblast mediated collagen matrix contraction.
Choroid ; Colchicine ; Collagen* ; Fibroblasts ; Interferons ; Puromycin ; Vitreoretinopathy, Proliferative

PURPOSE: To examine the renal injury by albumin infusion, which has been widely used to correct severe nephrotic edema, in puromycin aminonucleoside(PAN) induced nephrotic-range proteinuric rats. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were divided into 3 experimental groups, control group(PAN only, n=20), low-dose albumin group (PAN+25% albumin 1g/kg, n=20) and high-dose albumin group(PAN+25% albumin 4g/kg, n=20). PAN was peritoneally injected on day #1 and #7 to all experimental rats and 25% albumin was peritoneally injected from day #3 for three weeks. Twenty-four hour urine protein, serum creatinine and serum albumin were measured weekly. Histopathologic and ultrastructural examination using transmission EM, and immunohistochemical stainings of CD68, pan T, and L26 were done at 3 and 8 week. RESULTS: Twenty-four hour urine proteins at 2 and 3 weeks were significantly increased in high- dose albumin group compared to control and low- dose albumin group. Serum creatinine at 3 week in high-dose albumin group was 0.9+/-0.54mg/dL which was significantly higher than 0.6+/-0.31mg/dL of control group and 0.6+/-0.43mg/dL of low-dose albumin group. Serum creatinine at 8 week in high-dose albumin group was 1.2+/-0.85mg/dL which was significantly higher than 0.6+/-0.24mg/dL of control group and 0.6+/-0.21mg/dL of low-dose albumin group. Serum albumin was not different among groups. Percent(%) glomerular sclerosis at 8 week in high-dose albumin group was 9.4+/-5.8% which was significantly higher than 3.5+/-1.7% of control group. Interstitial mononuclear cell infiltration was increased according to albumin dose and most of them was CD68(+) macrophages. Vacuolar degeneration of podocytes, accumulation of protein reabsorption droplets in the cytoplasm of podocytes and proximal tubule and lipid droplets in the cytoplasm of proximal tubules were increasd according to albumin dose. CONCLUSION: Albumin infusion in PAN induced proteinuric rats load accelerate the decline in renal function by progressive glomerular and tubulo-interstitial injury. Albumin infusion in clinical nephrotic edema shoud be used very carefully.
Animals ; Control Groups ; Creatinine ; Cytoplasm ; Edema ; Macrophages ; Podocytes ; Puromycin Aminonucleoside* ; Puromycin* ; Rats* ; Rats, Sprague-Dawley ; Sclerosis ; Serum Albumin

PURPOSE: This experimental study was conducted to determine serial morphological changes of rat's kidney with chronic puromycin aminonucleoside (PAN) nephropathy. Special emphasis was given to the occurrence of glomerular hypertrophy and its relationship to the subsequent development of focal segmental glomerulosclerosis(FSGS). METHODS: Sprague-Dawley rats weighing 200-230g were used and divided into control(n=9) and experimental group(n=15). Rats were given subcutaneous injections of PAN at a dose of of 2mg/100g body weight, or an equivalent volume of normal saline and six injection were given over a period of 9 weeks, at weeks 0, 1, 3, 5, 7 and 9. At weeks 4, 8 and 11, rats were sacrificed and kidney weight, kidney weight/body weight(%) and various laboratory tests including serum protein and albumin were determined. Renal tissues were prepared with Histochoice(R) fixative and paraffin embedding for morphologic study. RESULTS: Kidney weight and kidney weight/body weight(%) were increased significantly in experimental group compared to controls at 4, 8 and 11 weeks. Heavy proteinuria along with lowering of serum protein and albumin and elevation of serum cholesterol was seen in experimental group at week 4 and this change became more marked on weeks 8 and 11. The frequency of FSGS in experimental animal, at week 4, 8 and 11 were 0.6%, 10.6% and 26.2% respectively(p<0.05) and the development of FSGS was more marked in juxtamedullary glomeruli compared to cortical glomeruli. Glomerular surface area showed significant increase in experimental animals compared to controls(p<0.01), the percentage of increase being 12.0, 14.7 and 12.3% at week 4, 8 and 11. And the surface areas of juxtamedullary glomeruli were larger than those of cortical glomeruli throughout the study period. CONCLUSION: In summary, present study indicates that glomerular hypertrophy occurs and precedes the development of FSGS in rats with chronic PAN nephropathy and juxtamedullary glomeruli are more susceptible to developing FSGS compared to cortical glomeuli.
Animals ; Body Weight ; Cholesterol ; Hypertrophy* ; Injections, Subcutaneous ; Kidney ; Paraffin Embedding ; Proteinuria ; Puromycin Aminonucleoside* ; Puromycin* ; Rats* ; Rats, Sprague-Dawley ; Sclerosis*

Sodium retention is a hallmark of nephrotic syndrome. We investigated whether sodium retention is associated with changes of natriuretic peptide system at different stages (i.e., a sodium retaining stage and a compensatory stage) of nephrotic syndrome. At day 7 after PAN (puromycin aminonucleoside) injection, the urinary excretion of sodium was decreased, along with the development of ascites and positive sodium balance. The plasma and urinary ANP (atrial natriuretic peptide) immunoreactivities were increased. ANP mRNA expression was increased in the heart and kidney, whereas that of NPR (natriuretic peptide receptor)-A and NPR-C mRNA was decreased in the kidney. The expression of NEP was decreased in the kidney. At day 14, urinary excretion of sodium did not differ from the control. The plasma ANP level and heart ANP mRNA expression returned to their control values. The expression of ANP mRNA in the kidney was increased in association with increased urinary ANP immunoreactivities. The expression of NPR-A in the kidney became normal, whereas that of NPR-C kept decreased. The expression of NEP (neutral endopeptidase) remained decreased. These findings suggest that the increased renal ANP synthesis in association with decreased metabolism via NEP and NPR-C may play a compensatory role against the development of sodium retention in nephrotic syndrome. The decreased of NPR-A expression in the kidney may contribute to the ANP resistance at day 7. The subsequent recovery of NPR-A expression may play a role in promoting sodium excretion in later stage (at day 14).
Animals ; Ascites ; Atrial Natriuretic Factor ; Heart ; Kidney ; Nephrotic Syndrome ; Plasma ; Puromycin ; Puromycin Aminonucleoside ; Rats ; Retention (Psychology) ; RNA, Messenger ; Sodium

PURPOSE: To test whether the expression of beta-catenin, a component of podocyte as a filtration molecule, would be altered by puromycin aminonucleoside (PAN) in the cultured podocyte in vitro. METHODS: We cultured rat glomerular epithelial cells (GEpC) with various concentrations of PAN and examined the distribution of beta-catenin by confocal microscope and measured the change of beta-catenin expression by Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: We found that beta-catenin relocalized from peripheral cytoplasm to inner cytoplasm, therefore, intercellular separations were seen in confluently cultured cells by high concentrations of PAN in immunofluorescence views. In Western blotting of GEpC, PAN (50 microg/mL) decreased beta-catenin expression by 34.9% at 24 hrs and 34.3% at 48 hrs, compared to those in without PAN condition (P<0.05). In RT-PCR, high concentrations (50 microg/mL) of PAN also decreased beta-catenin mRNA expression similar to protein suppression by 25.4% at 24 hrs and 51.8% at 48 hrs (P<0.05). CONCLUSION: Exposure of podocytes to PAN in vitro relocates beta-catenin internally and reduces beta-catenin mRNA and protein expression, which could explain the development of proteinuria in experimental PAN-induced nephropathy.
Animals ; Ascorbic Acid ; beta Catenin ; Blotting, Western ; Cells, Cultured ; Cytoplasm ; Epithelial Cells ; Filtration ; Fluorescent Antibody Technique ; Glycyrrhetinic Acid ; Podocytes ; Proteinuria ; Puromycin ; Puromycin Aminonucleoside ; Rats ; RNA, Messenger

BACKGROUND: Nephrin, a recently identified protein, could be a slit diaphragm component and it has been suggested to play a crucial role in maintaining the glomerular filtration barrier. It has been reported that mutations in the nephrin gene lead to congenital nephrosis. However, the expression of nephrin in acquired glomerular disease has not yet been fully clarified. We induced nephrotic-range proteinuria in experimental animal and performed morphologic analysis with immunoelectron microscopy. This study was designed to examine the expression and distribution of nephrin in acquired glomerular disease and to suggest a role of nephrin in pathogenesis of proteinuria. METHODS: Twenty-three rats were divided into 3 experimental groups and control(n=6). 17 rats of experimental groups had intravenous injection of puromycin aminonucleoside(PAN) singly, and were sacrificed at 1 week(n=5), 2 weeks(n=6) and 3 weeks(n= 6) later. The expression of nephrin was observed by immunoelectron microscopy employing the polyclonal antibody against nephrin and gold particle. For quantifications, the gold particles were counted from photographs. RESULTS: The average length of foot process in 1 week group(2,307+/-524 nm) was far greater than that of control(317+/-45 nm). The average number of total gold particles per unit length(10,000 nm) of the GBM was reduced at 1 week(4.4+/-1.3), compared with control(12.1+/-3.9). Also, the average number of junctional gold particles at 1 week(1.7+/-0.5) was decreased compared with control(6.7+/-2.2). No difference was observed in the number of junctional gold particles per slit diaphragm among groups. But, there were significant differences in the distribution of gold particles among groups. Gold particles were seen more frequently at apical plasma membrane and cytoplasm in 1 week group, whereas those were observed prominently at junctions in control. CONCLUSION: These data show that the expression of nephrin was decreased with effacement of foot process in PAN induced nephrosis rat. However, nephrin was preserved at not-damaged slit diaphragm. And the distribution of nephrin was changed in PAN nephrosis. Further studies for nephrin production and redistribution should be needed to understand pathogenesis of nephrotic syndrome.
Animals ; Cell Membrane ; Cytoplasm ; Diaphragm ; Foot ; Glomerular Filtration Barrier ; Injections, Intravenous ; Microscopy, Immunoelectron ; Nephrosis* ; Nephrotic Syndrome ; Proteinuria ; Puromycin Aminonucleoside* ; Puromycin* ; Rats*

An ultrastructural study was done on puromycin aminonucleoside (PAN) nephropathy which was induced in a group of Sprague-Dawley rats by a single intraperitoneally injected dose. To study the ultrastructural alteration of glomerular anionic sites renal tissue was stained with polyethyleneimine (PEI) as a cationic probe. The PEI method seemed to selectively stain heparan sulfate proteoglycan in the basement membrane and has been widely used to evaluate the changes of the basement membrane in human diseases as well as in experimental work. The experimental rats developed proteinuria three days after the PAN injection. Electron microscopic studies of glomeruli showed the loss of epithelial foot processes, formation of cytoplasmic vacuoles, microvillous formation, and increased numbers of lysosomes in the cytoplasm of podocytes. The anionic sites on the basement membrane with foot process fusion were mostly indistinguishable from those seen in control rats, but focal areas of loss or disarray of anionic sites were noted. The anionic sites were not seen on the basement membrane where the overlying epithelium was detached. The results suggest that proteinuria in PAN nephrosis may be primarily due to a glomerular epithelial lesion, leading to focal disarray of anionic sites or focal defects in the epithelial covering of the basement membrane. The loss of anionic sites in the basement membrane may result partially from the foot process fusion, but mostly from the epithelial detachment.
Animals ; Basement Membrane ; Cytoplasm ; Epithelium ; Foot ; Heparan Sulfate Proteoglycans ; Humans ; Lysosomes ; Nephrosis ; Podocytes ; Polyethyleneimine ; Proteinuria ; Puromycin Aminonucleoside* ; Puromycin* ; Rats ; Rats, Sprague-Dawley ; Vacuoles