• Journal of electromagnetic engineering and science
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• 제6권1호
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• pp.47-52
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• 2006

The objective of this study is to evaluate the effects of size and permittivity on the specific absorption rate(SAR) values of rat brains during microwave exposure at mobile phone frequency bands. A finite difference time domain (FDTD) technique with perfect matching layer(PML) absorbing boundaries is used for this evaluation process. A color coded digital image of the Sprague Dawley(SD) rat based on magnetic resonance imaging(MRI) is used in FDTD calculation with appropriate permittivity values corresponding to different tissues for 3, 4, 7, and 10 week old rats. This study is comprised of three major parts. First, the rat model structure is scaled uniformly, i.e., the rat size is increased without change in permittivity. The simulated SAR values are compared with other experimental and numerical results. Second, the effect of permittivity on SAR values is examined by simulating the microwave exposure on rat brains with various permittivity values for a fixed rat size. Finally, the SAR distributions in depth, and the brain-averaged SAR and brain 1 voxel peak SAR values are computed during the microwave exposure on a rat model structure when both size and permittivity have varied corresponding to different ages ranging from 3 to 10 weeks. At 900 MHz, the simulation results show that the brain-averaged SAR values decreased by about 54 % for size variation from the 3 week to the 10 week-old rat model, while the SAR values decreased only by about 16 % for permittivity variation. It is found that the brain averaged SAR values decreased by about 63 % when the variations in size and permittivity are taken together. At 1,800 MHz, the brain-averaged SAR value is decreased by 200 % for size variation, 9.7 % for permittivity variation, and 207 % for both size and permittivity variations.

• Toxicological Research
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• 제22권2호
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• pp.153-156
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• 2006

The acute toxicity of STB-HO-BM was evaluated in Sprague Dawley (SS) rats and beagle dogs. STB-HO-BM was administered orally to rats at dose levels of 0 and 2,000mg/kg/day and to dogs at dose levels of 0, 500, 1,000 and 2,000 mg/kg/day. In these experiments, there were no death and clinical changes which were related to STB-HO-BM administration. In addition, there were no significant changes between control and treated groups in body weights and autopsy findings. In conclusion, the administration of STB-HO-BM 2,000 mg/kg in SD rats and up to 2,000mg/kg in beagle dogs was proved to be safe, and it is thought that STB-HO-BM may not show any toxicity in its clinical use.

• 한국가축번식학회지
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• 제10권1호
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• pp.42-48
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• 1986

These experiments were carried out to develop new techniques identifying XX-bearing embryos prior to implantation by immunological method. Antiserum to histocompatibility-Y(H-Y) antigen was prepared in adult SD(sprague-dawley) female rat by repeated immunization of newbone testis supernatant from males of the same strain. ELISA test was used to identify the H-Y antibody of antiserum. Total 124 mouse embryos (8-cell stage) were treated with H-Y antiserum and complement in BSA free Ho, pp. and Pitt's medium and cultured under the gas phase of 5% CO2 in air at 37$^{\circ}C$ for 24 to 48 hrs. The morphological characteristics of embryos treated were observed under the phase-contrast micro scope. The results obtained in these experiments were summarized as follows: 1. Optimal Density of H-Y antibody were a, pp.ared to be 0.27-0.47 by ELISA test. 2. Of total 124 embryos treated with H-Y antiserum and complement 69(55.6%) embryos developed to blastocyst and 55(44.4%) destroyed or arrested.

• 한국식품영양과학회지
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• 제30권3호
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• pp.521-527
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• 2001

The effects of dietary restriction (DR) on antioxidant enzymes were studied in liver, lung and erythrocytes of diabetic rats. Experimental animals used Sprague-Dawley (SD; body weight 350$\pm$20g) male rats and Otsuka Long Evans Tokushima fatty (OLETE; body weight 5--$\pm$30g) male rats, as a model of type 2 diabetes mellitus. Type I diabetes was induced in SD rats by intramuscular injection of alloxan (80 mg/kg BW). Animals were randomly assigned either to continue the ad libitum diet or 40% DR (60% intake of ad libitum diet) groups. The body weight was measured at every 2 weeks to 4 months following DR. The activities of antioxidant enzymes (superoxide dismutase (SOD), catalase, glutathione peroxidase (GSHPx) were measured in liver, lung and erythrocytes and the concentration of TBARS as a marker of reactive oxygen species-induced tissue injry was also measured in rats after 4 months 40% DR. The body weight 4 months after 40% DR of control SD, alloxian-diabetid SD and OLETE rats were 80%, 98% and 75% of each control groups, respectively. The activities of SOD, catalase and GSHPx in lung and erythrocytes of rats were not change by 40% DR but in 4 month 40% DR rat liver, the activities of SOD and catalase were increased in control SD, alloxan-diabetic SD, and OLETF groups. The concentration of TBARS in lung and erythrocytes was also not changed by 40% DR, while liver TBARS concentration was decreased in OLETF and control SD rats compared to each non-DR control rats. These results suggested that the body weight changes in diabetic rats by DR was more prominent in type 2 diabetes and changes of antioxidant enzymes is most prominent in liver by DR either type 1 and 2 diabetic rats.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.194-198
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• 2000

Taurine, 2-aminoethanesulfonic acid is widely distributed in animal tissues and has a variety of bio-logical activities. A recent worldwide study demonstrated beneficial effects of taurine on aging and age-associated disorders. In general, taurine levels in the brain decease when an animal is subjected to pathologic conditions such as ischemia-anoxia and seizure. But the taurine levles tend to increase in the brain in hypertensive state. In the present study, the blood-brain barrier (BBB) transport of [$^3$H]taurine was compared between spontaneously hypertensive rats (SHR) and normotensive Sprague-Dawley rats (SD) using intravenous injection technique in vivo. We also obtained pharmacokinetic parameters of plasma volume maker, [$^{14}$ C] sucrose and [$^3$H]taurine after inject to rats simulatenously. BBB permeability surface area product (PS) value of [$^3$H]taurine in SHR (16$\pm$2.9$\times$10$^{-3}$ ml/min/g) was significantly higher than that in SD (7.4$\pm$0.8$\times$10$^{-3}$ ml/min/g). There is also significant difference for brain uptake of [$^3$H]taurine between SHR (0.195$\pm$0.031%ID/g) and SD (0.058$\pm$0.003% ID/g). This is due to difference of area under the plasma concentration-time curve (AUC) and that of total clearance (Class) between SHR and SD. No significant difference was indicated from other organ uptakes such as lung, heart, liver SHR and SD. But also kidney uptake was much higher in SHR. In conclusion, [$^3$H]taurine in plasma was slowly eliminated in SHR than in SD and uptake of [$^3$H]taurine in SHR is much higher than that of SD. This results suggest increased taurine level in the brain in hypertension state have an any effect on the brain uptake of taurine.

• 한국식품영양과학회지
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• 제37권9호
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• pp.1120-1125
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• 2008

괴각 추출물을 농축하여 동결 건조해서 실험동물인 Sprague-dawley rats의 해당 식이에 0.5% 수준으로 첨가하여 4주간 사육하면서 체중은 3일 간격으로 섭취는 2일 간격으로 일정한 시각(오전 9시)에 측정하였으며, 활성산소 및 항산화 활성 측정은 2주 간격으로 측정하였다. 또한 실험이 종료된 후 실험동물을 단두 도살하여 혈청 중 total cholesterol, HDL-cholesterol, triglyceride, glucose, phospholipid를 측정하여 지질함량에 미치는 영향을 측정한 결과 아래와 같은 결론을 얻었다. 괴각 추출물을 Sprague dawley rats에 급여 후 식이섭취량, 식이효율 및 체중증가량을 측정한 결과 각 군 간에 차이를 보이지 않았으며 2주 간격으로 항산화 활성 및 활성산소를 측정한 결과 2주째부터 항산화에서 차이를 보였으며 활성산소 생성량은 대조군과 비교했을 때 큰 차이가 없었다. 4주 후 괴각 추출물 급여군의 항산화 값은 대조군에 비해 17.04%로 높게 나타났다. 실험식이 종료 후 실험동물에서 적출한 장기의 무게를 측정한 결과 심장, 신장, 장, 간 모두 커다란 차이를 보이지 않았다. 또한, 혈청중의 total cholesterol 함량 측정 결과 괴각 추출물 급여군이 대조군에 비해 낮은 함량을 나타내었고, HDL-cholesterol 함량에서는 대조군에 비해 높은 함량을 보였다. Triglyceride 함량은 거의 차이가 없었으며 glucose 함량은 대조군에 비해 낮았고, phospholipid 함량은 높았으나 차이가 없었다. 이상에서와 같이 괴각 추출물을 이용한 동물실험에서 항산화 활성 및 혈청의 지질대사에 개선 효과가 있음을 확인하였다. 향후 이들 추출물을 항산화활성 및 지질대사 개선에 기능성을 갖는 식품소재로의 이용 가능성이 기대되며 향후에 추출물 투여농도의 증가나 투여기간의 연장에 따른 추가적인 연구가 필요하다고 사료된다.

• Toxicological Research
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• 제17권2호
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• pp.115-121
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• 2001

Some of endocrine disruptors with sexual hormone-like effects have been increasingly reported to be immunotoxic in many species in recent several years. Phthalate esters have possible effects on the endocrine system. Prenatal exposure to di(n-butyl) phthalate (DBP) has been reported to impair the androgen-dependent development of the male reproductive tract in rat. Therefore, the immunomodulatory effect of DBP was investigated in the developing immune system of fetal and neonatal Sprague-Dawley rats. Timed-bred pregnant SD rats were given to the doses of 0, 250, 500, and 750 mg DBP/kg$\cdot$ body weight /day by gavage once a day from gestational day (GD) 5 to 18. On GD19 or GD22/postnatal day one (PD1), the dams were euthanized, and the changes in organ weights and thymus phenotypes were examined for their offsprings. At 750 mg DBP/kg$\cdot$b.w./day in maternal exposure group, GD19 fetuses showed decreases in body weight. The spleen/body weight ratios were reduced in GD 19 fetuses from the dams exposed to 500 and 750 mg DBP/kg$\cdot$b.w./day. There were no significant changes in thymus and spleen cellularities though these cellularities showed a tendency to decrease in a dose dependent way. In the DBP-exsposed GD22/PD1 offsprings, the body weights, the relative organ weights and the cellularities did not exhibit alteration. Additionally, the percentages of CD3$^{+}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) and CD3$^{-}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) thymocyte subsets were not changed in any DBP-treated group. The proliferative responses of splenic T cells to Con A and B cells to LPS were decreased in all DBP-exposed GD22/PD1 offsprings.

• 대한약침학회지
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• 제18권4호
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• pp.38-44
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• 2015

Objectives: Radix Ginseng has been used for thousands of years to treat a wide variety of diseases. Radix ginseng has also been used as a traditional medicine for boosting Qi energy and tonifying the spleen and lungs. Traditionally, its effect could be obtained orally. Nowadays, a new method, the injection of herbal medicine, is being used. This study was performed to investigate the single-dose intravenous toxicity of water-soluble ginseng pharmacopuncture (WSGP) in Sprague-Dawley (SD) rats. Methods: All experiments were carried out at Biotoxtech, an institute authorized to perform non-clinical studies under the regulation of Good Laboratory Practice (GLP). At the age of six weeks, 40 SD rats, 20 male rats and 20 female rats, were allocated into one of 4 groups according to the dosages they would receive. The WSGP was prepared in the Korean Pharmacopuncture Institute under the regulation of Korea-Good Manufacturing Practice (K-GMP). Dosages of WSGP were 0.1, 0.5 and 1.0 mL/animal for the experimental groups, and normal saline was administered to the control group. The rat's general conditions and body weights, the results of their hematological and biochemistry tests, and their necropsy and histopathological findings were investigated to identify the toxicological effect of WSGP injected intravenously. The effect was examined for 14 days after the WSGP injection. This study was performed under the approval of the Institutional Animal Ethics Committee of Biotoxtech. Results: No deaths were found in this single-dose toxicity test on the intravenous injection of WSGP, and no significant changes in the rat's general conditions and body weights, the results on their hematological and biochemistry test, and their necropsy findings were observed during the test. The local area of the injection site showed minial change. The lethal dose was assumed to be over 1.0 mL/animal in both sexes. Conclusion: These results indicate that WSGP is safe at dosages up to 1 mL/animal.

• 대한의생명과학회지
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• 제27권2호
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• pp.69-76
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• 2021

The aim of this study was to evaluate gamma-aminobutyric acid (GABA)-induced erythropoietin (EPO) and EPO-receptor expression in human Hep3B cells and Sprague Dawley (SD) rats during hypoxia. Expression levels of EPO, EPO-R mRNA, Janus kinase-2 (JAK-2), vascular endothelial growth factor (VEGF), hypoxia inducible factor-1 (HIF-1), and HIF-2 in response to GABA treatment were evaluated in cell lines. SD rats were randomly divided into 5 groups of 8 rats each, and GABA was orally administered; the groups were the normal control (NC), hypoxia-exposed (G0), as well as the GABA 1 mg/100 g body weight (BW) GABA treated group (G1), 5 mg/100 g BW GABA treated group (G5), and 10 mg/100 g BW GABA treated group (G10) with hypoxia. We analyzed EPO levels and red blood cell counts in rat blood and EPO gene expression in kidney tissue. EPO and VEGF mRNA levels in Hep3B cells exposed to hypoxia were significantly increased and further increased after GABA treatment. However, the expression of EPO-R and JAK-2 mRNAs were not affected by GABA, but hypoxia-induced HIF-1 and HIF-2 mRNA expression was inhibited by GABA. In the kidney tissue of rats exposed to hypoxia, the expression level of EPO mRNA was greatly increased, but levels in the GABA treatment groups significantly decreased. EPO levels in the serum showed the same significant trend, but the red blood cell counts were not significantly different. These findings demonstrate that HIF-1 and HIF-2 activation increase EPO expression in Hep3B cells exposed to hypoxia. However HIF decreased by GABA addition and VEGF increased significantly.

• 대한의생명과학회지
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• 제22권2호
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• pp.53-59
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• 2016

Alcoholism is a significant health problem in the world. The liver is the first and primary target organ for alcohol metabolism. Alcohol dehydrogenase and aldehyde dehydrogenase play important roles in the metabolism of alcohol and aldehyde. In this study, I aimed to investigate the eliminatory effects of a Phellinus spp. extract on alcohol metabolism in drunken Sprague-Dawley (SD) rats. Male SD rats were given Phellinus spp. extract at 30 min after 40% (5 g/kg) alcohol ingestion. To assay the effect of Phellinus spp. extract on blood alcohol concentration, blood samples were taken from the tail vein at 1, 3 and 5 h after alcohol ingestion. The concentrations of alcohol, alcohol dehydrogenase, and aldehyde dehydrogenase in Phellinus spp. extract treated rat were significantly lower than that of the control with a time-dependent manner. In addition, the alanine aminotransferase and aspartate aminotransferase activities of Phellinus spp. extract-treated groups were altered compared to those of the control group. These results suggest that Phellinus spp. extract intake can have a positive effect on the reduction of alcohol, alcohol dehydrogenase, and aldehyde dehydrogenase concentrations in the blood and may alleviate acute alcohol-induced hepatotoxicity by altering alcohol metabolic enzyme activities. Phellinus spp. extract is thus a good nutraceutical candidate.