• Toxicological Research
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• v.13 no.1_2
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• pp.131-138
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• 1997

Group of 40 male and 40 female Sprague-Dawley rats were given daily intravenous injections of different dosage of Erythropoietin (EPO), 80 IU/ kg/day (low dosage group), 400 IU/ kg/day (middle dosage group), or 2000 IU /kg/day (high dosage group)for 4 weeks by tail vein according to Established Regulation of Korean National Institute of Safety Research (1994. 4. 14). Appearance, behavior, mortality, and food consumption of rats of treated groups were not affected during the experimental periods. No significant EPO (erythropoietin)-related changes were found in urinalysts, eye examination, hematology, serum chemistry, and organ weight. No histopathological lesions were observed in both control and treatment groups. Our results strongly suggest that no toxic changes were found in rat treated intravenously with EPO (erythropoietin)for 4 weeks.

• YAKHAK HOEJI
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• v.58 no.4
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• pp.223-228
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• 2014

The present study was undertaken to investigate the influence of sulforaphane on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that sulforaphane, the primary ingredient of broccoli of cruciferous vegetables, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Intact of denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, sulforaphane significantly inhibited fluoride, phorbol ester or thromboxane $A_2$ mimetic-induced contraction in denuded muscles suggesting that additional pathways different from endothelial nitric oxide synthesis such as inhibition of Rho-kinase or MEK might be involved in the vasorelaxation. Furthermore, sulforaphane inhibited thromboxane $A_2$-induced increases in pERK1/2 levels suggesting the mechanism including inhibition of thromboxane $A_2$-induced increases in ERK1/2 phosphorylation. This study provides evidence that sulforaphane induces vascular relaxation through inhibition of Rho-kinase or MEK in rat aortae.

• YAKHAK HOEJI
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• v.57 no.5
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• pp.376-381
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• 2013

The present study was undertaken to investigate the influence of curcumin on vascular smooth muscle contractility and to determine the mechanism involved. We hypothesized that curcumin, the primary ingredient of Curcuma longa, plays a role in vascular relaxation through inhibition of Rho-kinase in rat aortae. Denuded arterial rings from male Sprague-Dawley rats were used and isometric tensions were recorded using a computerized data acquisition system. Interestingly, curcumin inhibited fluoride-induced contraction but didn't inhibit phorbol ester-induced contraction suggesting that additional pathways different from endothelial nitric oxide synthesis might be involved in the vasorelaxation. Furthermore, curcumin significantly inhibited fluoride-induced increases in pMYPT1 levels. On the other hand, it didn't significantly inhibit phorbol ester-induced increases in pERK1/2 levels suggesting the mechanism involving inhibition of fluoride-induced MYPT1 phosphorylation. This study provides evidence that curcumin induces vascular relaxation through inhibition of Rho-kinase in rat aortae.

• Toxicological Research
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• v.16 no.1
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• pp.59-61
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• 2000

A single nucleotide polymorphism in the transforming growth factor-$\beta$ type II receptor (TGE$\beta$RII) gene of the rat was studied. TGF$\beta$RII is a tumor suppressor that is frequently inactivated by mutation in human colon cancers. A novel nucleotide polymorphism of G to A(or A to G), which causes a silent mutation at codon 129, was found in G:C rich sequence in the TGF$\beta$RII gene of Sprague-Dawley rats. The results suggest that genetic polymorphism occures without a strain of the laboratory animal.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.601-607
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• 1994

This study was carried out to investigate the potential of phenol to induce embryotoxicity in the Sprague-Dawley rat. Seventy mated rats were distributed among three treated troups, a vehicle control group and a negative control group. Phenol was at dose levels of 20, 60 and 180mg/kg/day adminsistered by gavage to pregnant rats three times per day from days 7 to 12 of gestation. All dams were subjected to the caesarean section on day 20 of gestation. At 120mg/kg, dams exhibited decreased locomotivity. In addition, both weight reduction and retarded ossification of fetuses were observed. There were no signs of maternal toxicity or embryotoxicity at 20 and 60mg/kg. The results show that phenol induces fetal growth retardation at maternally subtoxic dose in rats.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.297-302
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• 2003

This study was designed to determine whether selenium (Se) nutrition affects pulmonary glutathione peroxidase and alveolarization in the neonatal rat. Twenty-four female Sprague Dawley rats were bred and fed a semipurified Se-deficient (0.04 ppm, Se-) or a Se-adequate (0.5 ppm, Se+) diet through pregnancy and lactation. Pulmonary DNA synthesis was slightly higher in Se+ pups than in Se- pups on d 6 and d 9 of lactation, but significant difference was not found. As pulmonary alveolarization progressed, mean air space size decreased and internal surface area and lung volume increased. No difference in pulmonary alveolarization was found between Se- and Se+ pups by age. Pulmonary Se concentration was higher in Se+ pups than in Se- pups at all age. Glutathione peroxidase activity in lung tissur reflected Se status and was lower in Se- pups than in Se+ pups. In conclusion, selenium has no significant effect on alveolarization of neonatal lungs. but it is necessary for adequate supply of pulmonary antioxidant, glutathione peroxidase.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.7
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• pp.674-678
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• 2008

Low level laser therapy has various therapy effects. This paper performed the basic study for fabricating the low level laser therapy apparatus, and one of the goals of this paper was to make this apparatus used handily. The apparatus has been fabricated using the laser diode and microprocessor unit. The apparatus used a 635 nm laser diode for laser medical therapy and was designed for a pulse width modulation type to increase stimulation effects. In this study, the designed device was used to find out how 635 nm laser diode affected the skin injury of SD-Rat(Sprague-Dawley Rat). We divided the participants into two groups; irradiation group which was irradiated 10 minutes a day for 9 consecutive days, and none irradiation group. The results showed that the study group had lower incidence of inflammation and faster recovery, compared with the control group.

• Toxicological Research
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• v.22 no.3
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• pp.237-244
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• 2006

Two kinds of sepiolite, a $500^{\circ}C$ heat-treated sepiolite, and a $700^{\circ}C$ heat-treated sepiolite were analyzed for their physicochemical properties. After these sepiolites were instilled into rat lungs, the effects of the substances on lung pathological changes were evaluated. The lungs instilled with sepiolite increased their weight compared with the unexposed control. The pathological examination further showed increased legions of granuloma with early fibrosis. The heat treated sepiolites, however, did not show any toxicological differences from the untreated sepiolites. Thus chronic experiments are needed to evaluate the durability of mineral fibers, which is an essential experiment for evaluating biopersistence of fibers in lungs.

• Journal of Environmental Science International
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• v.6 no.1
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• pp.53-60
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• 1997

The toxicity of purified ricln from Ricinus communis to rats was examined by histological and histochemical methods. Sprague-Dawley rats were injected intraperitoneally with 75$\mu\textrm{g}$/kg body weight of ricin and were sacrified at itntervals of 6, 24, 48 and 120 hours after injectoon. The major morphological changes, such as cloudy swelling, hydropic degeneration, necrosis, fatty change, blood congestion, increase of Kupffer cells in number and extension of sinusoids, were obvious in the liver of experimental group. These morphological changes of hepatic cells were mainly observed in both the periportal and midlobular region of hepatic lobule. The extension of sinusoids was obvious in the controlobular region. And glycogen dlstrlbution of hepatic cells tended to decrease in the same region showing morphlogical changes as compared with the control group.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.1
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• pp.42-46
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• 2011

Light can be divided into ultraviolet rays, visible rays, and infrared rays depending on the wavelengths. Visible rays with specific wavelength are those predominantly used for would treatment. Especially low level laser irradiates into cells, effectively stimulating cellular tissues and activating cellular function. This study was intended to verify the effect of white LED irradiation therapy on wound recovery in animal tests by applying white LED irradiator, which was independently designed and developed to emit beams of similar wavelength to that of a laser. The designed LED Irradiator was used to find out how white LED light source affected the skin wound of SD-Rat(Sprague-Dawley Rat). We divided the participants into two groups; white LED irradiation group which was irradiated 1 hour a day for 9 consecutive days, and none irradiation group. The results showed that the study group had lower incidence of inflammation and faster recovery, compared with the control group.