We report a histiocytic sarcoma originating from the epididymis observed in a 110-week-old male CD-1 mouse in a carcinogenicity study. At necropsy, no lesions were observed in the epididymis. Histologically, a neoplastic lesion was observed in the cauda of the epididymis that was well demarcated from the surrounding tissues.
View Article and Find Full Text PDFEnarodustat (JTZ-951) is an oral hypoxia-inducible factor-prolyl hydroxylase (HIF-PH) inhibitor for the treatment of anemia with chronic kidney disease. Carcinogenicity of enarodustat was evaluated in a 26-week repeated oral dose study in Transgenic rasH2 (Tg.rasH2) mice and a 2-year repeated oral dose study in Sprague-Dawley (SD) rats.
View Article and Find Full Text PDFEthionamide (ETH), a second-line drug for multidrug-resistant tuberculosis, is known to cause hepatic steatosis in rats and humans. To investigate predictive biomarkers for ETH-induced steatosis, we performed lipidomics analysis using plasma and liver samples collected from rats treated orally with ETH at 30 and 100 mg/kg for 14 days. The ETH-treated rats developed hepatic steatosis with Oil Red O staining-positive vacuolation in the centrilobular hepatocytes accompanied by increased hepatic contents of triglycerides (TG) and decreased plasma TG and total cholesterol levels.
View Article and Find Full Text PDFSpontaneously Diabetic Torii (SDT) rats are a well-known animal model of non-obese type 2 diabetes mellitus. Although this animal model has been studied extensively over the last decade, the incidence rates of Leydig cell hyperplasia and tumors in this model have not been reported. In this study, pathophysiological analyses of the testes were performed on male SDT rats, to understand the effect of insulin treatment on the development of Leydig cell hyperplasia and tumors and the expression of integrins and extracellular matrix proteins.
View Article and Find Full Text PDFSarcopenia is the age-related decrease of muscle mass and function. Diabetes and obesity are known to be risk factors that exacerbate sarcopenia, but the underlying mechanism of diabetes-related sarcopenia is still unknown. Obese type 2 diabetes SDT fatty rats show early onset of severe diabetes and there have been no reports on the characteristics of their skeletal muscle.
View Article and Find Full Text PDFThe Spontaneously Diabetic Torii (SDT) rat is a rat model of nonobese type 2 diabetes mellitus, and hepatocellular adenomas have not been reported in this model. We report a hepatocellular adenoma with severe fatty change in a male 42-week-old SDT rat fed a high-fat diet. At necropsy, the animal had a whitish nodular mass of approximately 2 cm in diameter in the right medial lobe.
View Article and Find Full Text PDFThe spontaneously diabetic torii (SDT) fatty rat is a new model of type 2 diabetes showing overt obesity, hyperglycemia and hyperlipidemia. With early onset of diabetes mellitus, diabetic microvascular complications, including nephropathy, peripheral neuropathy and retinopathy, are observed at young ages. In the present study, blood glucose levels of female SDT fatty rats were controlled with phlorizin, a non-selective SGLT inhibitor, to examine whether and how these complications are caused by hyperglycemia.
View Article and Find Full Text PDFCell clusters were observed in the seminiferous tubules of C57BL/6J mice as a spontaneous lesion in a 2-week toxicity study, and they were demonstrated to be basically composed of Sertoli cells by immunohistochemistry for claudin-11 and GATA-4 (GATA-binding protein 4), which are both Sertoli cell markers. The clusters were composed of about 5 to 50 cells, which had eosinophilic and occasionally vacuolated cytoplasm with an unclear cell boundary. The cell clusters involved some sperm.
View Article and Find Full Text PDFWe report uveitis observed in an obese type 2 diabetes rat model, Spontaneously Diabetic Torii Lepr(fa) (SDT fatty) rats aged over 50 weeks. The eyes of SDT fatty rats (16 animals: 7 males and 9 females with 50 or 60 weeks of age) were examined histopathologically. Infiltration of inflammatory cells in the uveal tract was observed in 13 of 16 animals.
View Article and Find Full Text PDFThe Spontaneously Diabetic Torii (SDT) fatty rat is a new model for obese type 2 diabetes. The aim of the present study was to investigate the effect of 1/2 nephrectomy (Nx) on renal function and morphology and on blood pressure in SDT fatty rats. Male SDT fatty rats underwent 1/2 Nx or a sham operation (Sham).
View Article and Find Full Text PDFWe overviewed the pathophysiological features of diabetes and its complications in obese type 2 diabetic rat models: Otsuka Long-Evans Tokushima fatty (OLETF) rat, Wistar fatty rat, Zucker diabetic fatty (ZDF) rat and Spontaneously diabetic Torii (SDT) fatty rat. Pancreatic changes with progression of diabetes were classified into early changes, such as islet hypertrophy and degranulation of β cells, and degenerative changes, such as islet atrophy and fibrosis of islet with infiltration of inflammatory cells. Renal lesions in tubuli and glomeruli were observed, and nodular lesions in glomeruli were notable changes in OLETF and SDT fatty rats.
View Article and Find Full Text PDFSalt plays an important role in the control of blood pressure in obesity and diabetes mellitus. In this study, we investigated physiological changes such as blood pressure and renal function in salt-loaded female Spontaneously Diabetic Torii-Lepr(fa) (SDT fatty) rats. SDT fatty rats were given 1% NaCl in drinking water for 14 weeks, from 4 to 18 weeks of age.
View Article and Find Full Text PDFSpontaneously Diabetic Torii Lepr (fa) (SDT fatty) rat, established by introducing the fa allele of the Zucker fatty rat into SDT rat genome, is a new model of obese type 2 diabetes. Both male and female SDT fatty rats show overt obesity, and hyperglycemia and hyperlipidemia are observed at a young age as compared with SDT rats. With early incidence of diabetes mellitus, diabetic complications, such as nephropathy, retinopathy, and neuropathy, in SDT fatty rats were seen at younger ages compared to those in the SDT rats.
View Article and Find Full Text PDFBackground/aims: Ferric citrate hydrate (JTT-751) is being developed as a treatment for hyperphosphatemia in chronic kidney disease patients, and shows serum phosphorus-reducing effects on hyperphosphatemia in hemodialysis patients. We examined whether JTT-751 could reduce phosphorus absorption in normal rats and prevent the progression of ectopic calcification, secondary hyperparathyroidism and bone abnormalities in chronic renal failure (CRF) rats.
Methods: Normal rats were fed a diet containing 0.
Spontaneously Diabetic Torii (SDT) rat is a hereditary model of diabetes. Although the SDT rat shows severe diabetic complications, the onset of hyperglycemia is late. SDT fatty rat, established by introducing the fa allele of the Zucker fatty rat to SDT rat, develops diabetes much faster than SDT rat.
View Article and Find Full Text PDFThe present report describes a rare case of spontaneous primary histiocytic sarcoma of the popliteal lymph node in a 19-week-old female Sprague-Dawley (SD) rat. At necropsy, a 10 mm-diameter whitish nodule was found at the site of the femoral muscle in the right hindlimb. Histopathologically, the nodule comprised large pleomorphic histiocyte-like cells with abundant eosinophilic or foamy cytoplasm.
View Article and Find Full Text PDFIn this report, we describe a case of neuroendocrine carcinoma of undetermined origin in a dog. Necropsy revealed scattered small neoplastic nodules in the bilateral lungs and a small nodule in the parapancreatic lymph node. Histopathologically, both pulmonary and lymph nodal nodules showed a similar histologic pattern, with neoplastic cells being arranged in diffusely proliferating sheet-like cellular nests separated by variable amounts of fibrous septa, sometimes forming rosettes and duct-like structures.
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