• Clinical and Experimental Reproductive Medicine
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• v.21 no.3
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• pp.297-303
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• 1994

The effect of radiation on the steroidogenesis of rat ovary was investigated. For this purpose, female rats aged 7-8 weeks were exposed to a single dose of ${\gamma}$ radiation(320 rad or 800 rad) by the cobalt-60. At fourth(day of the first estrus) and eighth(day of the second estrus) days after irradiation, the concentrations of serum steroid hormones were determined by radioimmunoassays (RIA). The correlation between survival rate(Y) and radiation dose(X) was Y=-0.06X+100(r=0.89, n=10). Lethal dose$(LD)_{50(30)}$ and $LD_{20(30)}$ were 833.33rad and 333.33rad respectively. The weights of body and ovary was decreased significantly by the $LD_{50(30)}$ irradiation during the 4 days, but both weights were recovered at day 8. The serum levels of 17a-hydroxyprogesterone(170HP) and estradiol($E_2$) in the irradiated rats were not generally different from those of control. However, the levels of testosterone(T) and 19-norterstosterone(19NT) in the irradiated rat at $LD_{50(30)}$ and $LD_{20(30)}$ radiation doses were decreased, while progesterone levels in serum of the irradiated rats were slightly increased. These results suggest that irradiation may inhibit the first step of steroidogenesis, especially the conversion of P to T, in the rat ovary.

• Journal of the Korean Magnetic Resonance Society
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• v.10 no.2
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• pp.126-140
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• 2006

Purpose: Contrary to the human study, it has rarely investigated metabolic alterations in the dorsolateral prefrontal cortex (DLPFC) of depressed rats versus age and sex-matched controls using proton magnetic resonance spectroscopy (MRS). Thus, the purpose of this research was to verify the feasibility of metabolic differences between the normal rat and the depression model rat. Materials and Methods: A homogeneous group of 20 SD male rats was used for MRI and in vivo 1H MRS. To induce a depressed status in SD rats, we performed the forced swimming test (FST). Using image-guide, water suppressed in vivo 1H MRS with 4.7 T MRI/MRS system, NAA/Cr and Cho/Cr ratios were mainly measured between depressed rats and normal subjects. Results: In depressed rats, increased Cho/Cr ratio was measured versus control subjects. However, no significant group effect for NAA/Cr was observed between case-control pairs. Discussion and Conclusions: The present 1H MRS study shows significant brain metabolic alterations of dorsolateral prefrontal cortex with experimental depressed status of SD rat induced by FST compared to normal subjects. This result provides new evidence that in vivo 1 H MRS may be a useful modality for detecting localized functional neurochemical markers alterations in left DLPFC in SD rats.

• Toxicological Research
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• v.14 no.4
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• pp.483-488
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• 1998

During cerebral ischemia two important factors such as hypoxia and reduction of glucose can act as modulating stressor affecting the release of amine neurotransmitters including 5-hydroxytryptamine (5-HT). This study was performed to investigate the effect of glucose deprivation on the oxygen deprivation-induced changes of [3H]-5-HT release in the rat hippocampal slices. Experimental groups were divided into 4 groups for this study: normoxic/normoglycemic group, oxygen-deprived group, glucose-deprived group, and oxygen/glucose-deprived group. The hippocampus of rat brain was sliced by 400 $\mu\textrm{m}$ thickness with manual chopper. After 30 minutes preincubation in the normal buffer, the slices were incubated for 20 min in buffer containing [3H]-5-HT (0.1 M, 74 $\mu\textrm$Ci) for uptake. To measure the release of [3H]-5-HT into the buffer, the incubation medium was drained of and refilled with fresh buffer every ten minutes through a sequence of 14 tubes. Oxygen deprivation by gassing with 95% $N_2$/5% $CO_2$ and/or glucose deprivation was done in the 6th and 7th tube. The radioactivities in each buffer and the tissue were counted using scintillation counter. The results were expressed as fractional release. When slices were exposed to oxygen-deprived media for 20 min, the diminution followed by the rebound release of [3H]-5-HT was observed during the post-oxygen deprived period. However, glucose deprivation or oxygen/glucose deprivation markedly increased the release of [3H]-5-HT. which was opposite to the pattern observed in oxygen-deprived group. These results suggested that oxygen deprivation itself inhibits [3H]-5-HT release in rat hippocampal slices during oxygen-deprived period, but additional glucose deprivation convert the inhibitory response to increase of [3H]-5-HT release.

• Journal of Applied Biological Chemistry
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• v.63 no.4
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• pp.365-373
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• 2020

We previously reported the potential of Senna tora L. seeds fermented by Lactobacillus casei (FSL) as a laxative agent in a loperamide-induced constipation rat model. Here, we examine the mechanism of action of FSL and its bioactive compound, revealed herein, on loperamide-induced constipation Sprague Dawley rat model. We identified the compound aurantio-obtusin (AO) using HPLC quantitative analysis. Rats were randomly assigned to six experimental groups (eight rats each)-normal and constipated groups (loperamide, FSL [100, 300, 500 mg/kg], and AO [1 mg/kg]). The FSL and AO-treated group showed an increase in the frequency, amount, and water content of feces in the constipated rat. Moreover, FSL and AO increased the intestinal transit speed in the constipated rat. Histological analysis revealed that FSL and AO recovered the intestinal mucus, the number of goblet cells, as well as thickness of the mucosa layer and muscle. Furthermore, the protein levels of the muscarinic acetylcholine receptor M3, which is involved in intestine contraction, were recovered in the FSL and AO-treated group. Its downstream signaling pathway (p-protein kinase C) was recovered by FSL and AO treatment. In conclusion, fermentation of S. tora L. seeds increases AO, which improves intestinal function, indicating that FSL is effective for treating constipation.

• The Korean Journal of Zoology
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• v.16 no.1
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• pp.13-23
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• 1973

The changes in the quantitative distribution and in cytoplasmic granules of tongue mast cells and duodenal enterochromaffin cells in male albino rats were observed following oral administration of 40mg/kg body wt. isonicotinic acid hydraside (INH) and 20mg/kg body wt. pyridoxine. The results obtained are summarized as follows: 1. INH administered-rat showed a marked decrease in the number of mast cells, caused by leakage of cytoplasmic granules, while pyridoxine-rat showed increased the number of mast cells. 2. Similarly, INH-rat showed a marked decrease in the number of enterochromaffin cells. In the case of pyridoxine-rat, however, the number of enterochromaffin cells increased compared with that of the controls. 3. In view of the fact that a large dose of INH was harmful to the formation of mast cells and enterochromaffin cells. And considering that a moderate dose of pyridoxine stimulated the formation of the two kinds of cells and the amounts of cytoplasmic granules, it was concluded that pyridoxine might be concerned with the metabolism of secretory products, 5-Hydroxytryptamine.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.4
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• pp.313-323
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• 2010

Purpose: This study was conducted to evaluate the effect of beta-tricalcium phosphate (Cerasorb$^{(R)}$, Germany) and deproteinized bovine bone (Bio-Oss$^{(R)}$, Switzerland) grafted to the defect of rat calvaria artificially created and the effect of use of absorbable membrane (BioMesh$^{(R)}$, Korea) on new bone formation. Materials and Methods: Transosseous circular calvarial defects with diameters of 5 mm were prepared in the both parietal bone of 30 rats. In the control group I, no specific treatment was done on the defects. In the control group II, the defects were covered with absorbable membrane. In the experimental group I, deproteinized bovine bone was grafted without absorbable membrane; in the experimental group II, deproteinized bovine bone was grafted with absorbable membrane; in the experimental group III, beta-tricalcium phosphate was grafted without absorbable membrane; in the experimental group IV, beta-tricalcium phosphate was grafted with absorbable membrane. The animals were sacrificed after 3 weeks and 6 weeks respectively, and histologic and histomorphometric evaluations were performed. Results: Compare to the control groups, the experimental groups showed more newly formed bone. Between the experimental groups, beta-tricalcium phosphate showed more resorption than deproteinized bovine bone. Stabilization of grafted material and interception of the soft tissue invasion was observed in the specimen treated with membrane. There was no statistical difference between the experimental group I, III and experimental group II, IV classified by graft material, but statistically significant increase in the amount of newly formed bone was observed in the experimental group I, II and II, IV classified by the use of membrane (P<0.05). Conclusion: Both beta-tricalcium phosphate and deproteinized bovine bone showed similar osteoconductibility, but beta-tricalcium phosphate is thought to be closer to ideal synthetic graft material because it showed higher resorption rate in vivo. Increased new bone formation can be expected in bone graft with use of membrane.

• Journal of Ginseng Research
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• v.4 no.2
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• pp.146-164
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• 1980

In this paper it was attempted to observe the effect of defatted panax ginseng supplement of the growth rate, feed and protein efficiency ratios, and the contents of cholesterol, total lipid and protein in the serum, liver and aorta in Sprague-Dowley Albino male rat (weighing 83 ${\pm}$ 4 g). Seven kinds of experimental diets were prepared as follows : Stock (control) diet, ginseng control diets supplemented with 0.5, 1.0 and 3.0% of ginseng powder to the stock diet, and defatted ginseng Powder diets supplemented with 0.5, 1.0 and 3.0% of defatted ginseng powder to the stock diet. .All diets contained same level of lipid and protein, respectively. The results obtained are as follows : 1. The growth rate in the feeding group of 0.5% defatted ginseng powder diet for 16week were higher than other diet groups. 2. Feed and Protein efficiency in 0.5% defatted ginseng group showed similar tendency to that in body growth rate. 3. The total cholesterol contents in the serum of 0.5% defatted ginseng Powder diet$.$ group showed the tendency to decrease gradually for 4 to 12 weeks, maintaining higher level than other groups. The free cholesterol contents in the serum of defatted ginseng powder diet group in 8 the and 16th weeks were higher than all ginseng control diet group. The total and free cholesterol contents in the liver of all defatted ginseng diet groups in 16th week were higher than hose of all ginseng control groups. The total cholesterol content at 12h week and the free cholesterol content at 16th week i n the aorta of all defatted ginseng diet groups were lower than those of ginseng control groups, respectively. 4. The total lipid contents in the serum of 1.0 and 3.0% defatted ginseng diet groups at 2nd to I2th weeks were lower than other groups, and those in the liver and aorta of all defatted ginseng diet groups at 12th weeks were lower than those of ginseng control diet groups. 5. The protein contents of the serum and aorta were continuously increased throughout whole experimental period in all experimental groups. The protein content of the liver of all groups were decreased at 2nd week and after then no change was observed.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.16 no.1
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• pp.41-48
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• 1986

It is known that radiation therapy is a kind of treatment choices of the maxillofacial tumors. This study is designed to investigate the irradiation effects on rat's periodontal tissues as functional tissues which relate to tooth-support, hard tissue formation and destruction. 20 rats (Sprague-Dowley branch, male) were devided into control group of 4 and experimental groupe of 16. Experimental group was singly exposed to Co-60 irradiation with 10 Gy in the head and neck region. Animals were sacrificed on 2 days, 1 week, 2 weeks and 3 weeks after the irradiation. The specimens were observed by histopathological examination employing H-E stain, van-Gieson stain and PA-ACH fluorescent stain. The results were as follows: 1. Cementoblasts and osteoblasts were gradually lost and rearranged along the external surfaces of the cementum and alveolar bone, but osteoclasts were almost not affected. 2. The cell numbers of the periodontal ligament were decreased due to the cellular atrophy and degeneration, but recovered almost normally on the 3rd week after irradiation. 3. The collagen fibers within the periodontal ligament were irregularly oriented, became finer and decreased in number. 4. The vessels of the periodontal ligament were decreased at the initial stage but increased again on the 2nd week after irradiation, and the hemorrhagic appearances, occurred within the tissues, due to the arterial destruction, were lasted until 3 weeks after irradiation. 5. The glycogen within the periodontal ligament was gradually increased and stored in the matrices of the cemental side on the 1st week after irradiation, but recovered almost normally on the 3rd week after irradiation.

• Imaging Science in Dentistry
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• v.36 no.1
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• pp.33-40
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• 2006

Purpose : To investigate clusterin expression in the acini and ductal cells of rat submandibular glands after Co-60 gamma irradiation. Materials and Methods : The male Sprague-Dawley rats weighing approximately 250 gm were divided into control and experimental groups. The experimental group was irradiated with a single absorbed dose of 2, 5, 10, and 15 Gy on the head and neck region. All the rats were sacrificed at 1, 3, 7, 14, 21, and 28 days after irradiation. The specimens including the submandibular gland were sectioned and observed using a immunohistochemical method. Results : In the 2 Gy group, clusterin expression was similar to that of the control group at 1 day after irradiation and it was observed in the striated ductal cells at 3 days after irradiation. In the 5 Gy group, clusterin expression was observed in the striated ductal cells at 1 day after irradiation and gradually increased in the 10 and 15 Gy groups. In the 15 Gy group, clusterin expression was prominent in the striated ductal cells at 1 day after irradiation, but it gradually decreased with the experimental period. The destruction of the striated ductal cells was observed in the 2 Gy group at 21 days after irradiation and in the 5, 10, and 15 Gy groups at 7 days after irradiation. The destruction of the acinar cells was observed in the 2 Gy group at 28 days after irradiation and in the 5, 10, and 15 Gy groups at 14 days after irradiation. Conclusion : Clusterin expression was induced by low doses of irradiation and it appeared to be involved in the regulation of cellular response to irradiation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.1
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• pp.27-40
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• 1990

In recent years, tissue antigens and enzymes that will serve as phenotypic markers for malignant cells are becoming increasingly important as diagnostic aids. This study was undertaken to investigate the specific activities of these enzymes in DMBA-induced rat submaxillary gland carcinogenesis. One hundred and twenty Sprague-Dawley rats about 100 gms of body weight were used. In experimental group, DMBA pellet (5mg) was implanted into right submaxillary gland and sham operation was performed into left gland to serve as control. The animals were sacrificed every three weeks up to 15 weeks. Submaxillary glands were excised on both sides and enzyme assays for ${\gamma}-glutamyl$ transpeptidase (GGT), 5'-Nucleotidase, Ornithine decarboxylase(ODC) and Acetyl-Co A carboxylase were carried out biochemically. The obtained results were as follows ; 1. In control group, there was no significant weight change of submaxillary gland, while experimental group, weight was increased remarkably about 7-fold at 15th week since DMBA implantation. 2. In control group, there was no change in specific activities of enzymes during the experimental period. 3. GGT activity was rapidly increased reaching a peak of 1.766${\pm}$0.082units/mg of DNA, 8-fold greater than that of onset. 4. 5'-Nucleotidase activity was increased reaching a peak of $362.1{\pm}53.2{\mu}moles/mg$ of DNA at 9th week. 5. ODC activity was rapidly increased, reaching a peak of 26.2${\pm}$4.8nmoles/mg of DNA at 9th week and quickly returned to that of control at 15th week. 6. Acetyl-Co A carboxylase activity was rapidly increased earlier than other enzymes, reaching a peak of 0.178${\pm}$0.013units/mg of DNA at 6th week and quickly declined to the control level at 15th week.