• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.375-381
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• 1995

Two intraocular tumors were identified in low and medium dosed groups of a carcinogenicity study using 200 males and 200 females Sprague-Dawley rats in Screening & Toxicology Research Center, Korea Research Institute of Chemical Technology. The tumors were grossly observed as white or yellow, unilateral nodules. They were approximately $1-2{\times}3-5mm$ in size. The tumors located in the region of iris and/or ciliary body invaded peripheral cornea. The microscopic features were usually composed of spindle cells arranged in parallel, forming gently curving bundles or whorls. The spindle cells had poorly defined cell boundaries, scant to moderate cytoplasm, fusiform nuclei and indistinct nucleoli. Mitotic figures were rare and areas of necrosis were present. The spindle cells had positive immunoreactivity for S-100 protein and vimentin but negative for desmin, collagen and HMB-45 antibody. In special histochemical studies, the spindle cells react with Gomori's stain for argyrophih fibers, Prussian blue stain for iron but negative with Masson-Fontana's stain for melanin granules. Ultrastructurally, cytoplasmic premelanosomes were not observed in the tumor cells due to the poor preservation of tumor masses. Based on the results, the tumors were diagnosed as amelanotic melanoma.

• Journal of Environmental Health Sciences
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• v.33 no.2 s.95
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• pp.132-136
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• 2007

The present study was carried out to examine the bone healing effect of a magnet as the feasibility test for clinical application. The surgical technique of tibia puncture was performed with male Sprague Dawley rats for investigating radiological and histological findings. The treated group was attached the magnet, and control group was attached the placebo magnet for 4, 6, and 8 weeks respectively. The rats were taken a radiograph for examining radiological findings on 2-weekly interval for 8 weeks. Also, the rats were partly euthanized for investigating histological findings on 2-weekly interval from 4 week to 8 week. In the magnet treated rats, the healing process of bone trauma was positively stimulated to compare with control rats.

• Korean Journal of Veterinary Research
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• v.32 no.2
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• pp.245-250
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• 1992

This study was performed to demonstrate the presence of large granular lymphocyte(LGL) in Sprague-Dawley(SD) rats and morphologically observe NK cell and also establish the method of isolation of natural killer cell in SD rats. By percoll discontinuous density gradients centrifugation, highly enriched LGL population were shown to fraction 2(border line between 44.2% and 50.8%). LGL were shown to bind selectively to YAC1 mouse lymphoma cell. This fraction expressed very high NK cell cytolysis. Therefore, we thought that LGL have NK activity in SD rats. The Morphology of rat LGL is very similar to that of human LGL. These cells have an eccentric kidney-shaped nucleus. Their most distinctive feature was their cytoplasmic azurophilic granules. Another distinguishing feature of rat LGL was their high cytoplasmic : nuclear ratio. It was concluded that LGL played a role part in mediating natural killer activity in this species.

• Nutritional Sciences
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• v.5 no.3
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• pp.117-122
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• 2002

This study was designed to observe the effect of conjugated linoleic acid (CLA) supplementation on body fatness, fat cell sizes and leptin levels in male Sprague Dawley rats. Following weaning, forty rats were divided into 4 groups beef tallow (BT), fish oil (FO). beef tallow with CLA supplementation (BTC), and fish oil with CLA supplementation (FOC) group. For four weeks, all rats were fed experimental diets containing 12％ of total dietary fat (w/w) with or without 1％ CLA. After 4 weeks, the animals were sacrificed; the total carcass fat, plasma leptin levels, epididymal fat pad weights and fat cell sizes in adipose tissue were measured. CLA supplementation did not significantly affect the rat's body weights, total body fat, epididymal fat pad weights, and fat cell sizes. CLA also did not have a significant effect on plasma leptin levels. These results suggest that CLA supplement was not an effective way to reduce the body weights of male Sprague Dawley rats.

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.39-42
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• 2001

A reference range data base containing organ weight values on animals used in 4 week and 13 week toxicity tests is described. Data listed include the values of minimum, maximum, mean and standard deviation for each of the following organ weights. Organs: Brain, heart, liver, spleen, kidney, adrenal gland, testis, ovary. This study was undertaken to determine organ weight reference values of Ktc: SD rats

• The Journal of Korean Medicine
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• v.34 no.3
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• pp.86-95
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• 2013

Objectives: Sprague-Dawley rats were fed with high fat diet, and atherogenic changes were seen in the aorta. However, when Sprague-Dawley rats were fed with a high fat diet and administered Youngyopaedoc-san together, these atherogenic changes were rarely seen. This study was aimed to find the inflammatory marker level changes in Sprague-Dawley rats with Youngyopaedoc-san-related anti-atherogenic effect. Methods: The extract from Youngyopaedoc-san was made by the pharmacy department of Kyung-hee Oriental Medical Hospital. The animals were divided into five groups: normal diet, high fat diet, high fat diet with Youngyopaedoc-san, high fat diet with Vytorin, and high fat diet with Youngyopaedoc-san and Vytorin. A light microscopic image of a cross section taken from the aorta of the Sprague-Dawley rat was analyzed. We compared inflammatory marker levels among the five groups. Results: The complex of Youngyopaedoc-san and Vytorin has more anti-atherogenic effects in the aorta of Sprague-Dawley rats fed with high fat diet than Vytorin alone. Youngyopaedoc-san has inhibitory effect on the increase of IFN-${\gamma}$ and IL-2 levels. The difference on eosinophil levels of each group was statistically significant, but the eosinophil level of each group was within normal limits, so the difference on eosinophil levels was not clinically significant. Conclusions: Youngyopaedoc-san-related anti-atherogenic effect could be a result of inhibitory mechanism on IFN-${\gamma}$ and IL-2.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.656-657
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• 2006

• Toxicological Research
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• v.18 no.4
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• pp.397-400
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• 2002

This study was carried out to investigate the acute toxicity of G. bimaculatus in Sprague-Dawley rats. G. bimaculatus was administered orally at doses of 8, 40, 200, 1000 and 5000 mg/kg. in this study, number of deaths, clinical sign, body weights, and pathological examination were investigated for 14 days after administration of G. bimaculatus. The results indicate that G. bimaculatus did not show any toxic effect in rats and oral $LD_{50}$ value was over 5000 mg/kg in Sprague-Dawley rats.

• YAKHAK HOEJI
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• v.43 no.3
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• pp.358-368
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• 1999

Subacute toxicity study was performed in Sprague-Dawley rats after daily dermal administration of Sangmosu (0.2, 1.0 and 5.0 g/kg) for one month. There were no clinical signs and pathological changes compared with control group. Bodyweights were not significantly changed between control and Sangmosu treatment groups. In histopathological examinations, there were some pneumonia in lung tissues at all groups of Sangmosu treatment including control, but it was not considered to be caused by Sangmosu. These results suggest that Sangmosu does not induce any significant subacute dermal toxicities in Sprague-Dawley rats.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.508-516
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• 2019

Objectives: The present study was performed to obtain acute toxicity information on glyoxal in male rats after intratracheal instillation. Methods: In order to calculate the LD₅₀ of glyoxal using Probit analysis with SAS, the test article was one intratracheal instillation to male Sprague-Dawley rats at dose levels of 0, 225, 451 or 902 mg/kg. During the test period, mortality, clinical signs, and body and organ weights were examined. At the end of the 14-day observation period, all animals were sacrificed and complete gross postmortem and histopathological examinations were performed. Results: Four animals of the 902 mg/kg group died within one week after the administration of glyoxal. All treatment group in a dose dependent manner, decreased body weight was found during the study period. The absolute and relative lung weight, and histopathological changes (bronchiolar-alveolar hyperplasia, chronic inflammation) of lung exhibited an increased in glyoxal treated groups in a dose dependent manner. However, there were no changes on the organ weights and histopathological changes of any other organ except lung. Conclusions: The results obtained in the present study suggest that the LD₅₀ in male Sprague-Dawley rats after a single intratracheal instillation of glyoxal was considered to be 866.9 mg/kg and the lung was found to be the target organ for glyoxal.