• Journal of Nutrition and Health
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• v.30 no.10
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• pp.1160-1169
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• 1997

The purpose of this research was to investigate the effects of caffeine and calcium levels on calcium utilization in female rats of different ages. Calcium utilization was compared in female rats of different age( 4 weeks and 12 months) fed various levels of caffeine(0 and 7 mg/100g body weight) and calcium (50, 100 and 200% of requirement) for 3 weeks. Feed intake of the caffeine groups were lower than that of the no-caffeine groups. body weight gain was lowest in the high-caffeine and low-calcium group. Serum calcium levels of young rats were higher than those of adult rats. There were no significant differences in tibial calcium content among the caffeine and calcium -groups. Fecal calcium excretion increased as the level of dietary calcium was increased. Urinary calcium excretion increased as the levels of caffeine and dietary calcium were increased. With increasing levels of dietary calcium , daily calcium retention was accelerated, but apparent calcium absorbability was diminished. The results of this study suggest that caffeine consumption promotes urinary calcium excretion. However, increase in dietary calcium resulted in higher calcium retention . These findings indicate that high caffeine consumption may increase dietary calcium requirements. Therefore, it could be suggested that the supplementation of dietary calcium may counteract the negative effect of caffeine intake on calcium utilization.

• Toxicological Research
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• v.17 no.4
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• pp.273-277
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• 2001

Though the bamboo salt, called as "JUKYUM" has been widely used in Korea as panacea, it's toxicity were not screened completely. To investigate the toxicity of bamboo salt, we compared with the toxicity of crude salt and reagent-grade NaCl by performing single dose oral toxicity test in SD rats. Crude salt, natural sun-dried salt (crude salt) production, was purchased from the western seashore of Korean peninsular, and reagent-grade NaCl was purchased from Sigma company. Results of the single dose oral toxicity tests on bamboo salt, crude salt and reagent-grade NaCl to SD rats are as follows, $LD_{50}$ of bamboo salt was 4174mg/kg (male) and 4074mg/kg (female), that of crude salt was 4871mg/kg (male) and 4898mg/kg (female) and that of reagent-grade NaCl was 4247mg/kg (male) and 4025mg/kg (female), respectively. There were little differences in clinical signs and gross legions among groups. Finding of gross autopsy and necropsy of bamboo salt treated group were similar to other groups.er groups.

• Korean Journal of Pharmacognosy
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• v.40 no.2
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• pp.89-98
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• 2009

The toxicity of aristolochic acid (ArA) has attracted considerable attention since the case of nephropathy regarding diet pill preparations was reported. The present study was performed to determine the reproductive toxicity of ArA in female SD rats. ArA was administered orally to female rats at 2, 8 or 16 mg/kg b.w./day and the females were mated with untreated males and their reproductive status was determined. ArA is well known as PLA2 inhibitor, toxic effects of such a relationship are not yet clear, and in vivo study on this matter are scarce. For this study, ArA was administered to pregnant rats at 10 or 20 mg/kg b.w./day, because premating treatments were not conducted. Administration of 20 mg/kg b.w./day caused infertility or abortion. In ArA-treated groups, PGF2a productions were inhibited and apoptosis were suppressed. Collectively, this study may help to further define the roles of sPLA2 in reproductive organs and to determine the toxic mechanisms of ArA.

• Korean Journal of Exercise Nutrition
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• v.24 no.4
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• pp.24-27
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• 2020

[Purpose] Dehydroepiandrosterone (DHEA) administration reportedly recovers osteoporosis, a bone disorder associated with bone deficiency in postmenopausal women. However, the physiological mechanism of DHEA in osteoporosis remains elusive, especially in terms of intestinal calcium absorption. Therefore, we investigated the effect of DHEA administration on calcium absorption in ovariectomized (OVX) female rats using an estrogen receptor antagonist. [Methods] Female Sprague-Dawley rats (n=23, 6 weeks old) were randomized into three groups: OVX control group (OC, n=7), OVX with DHEA treatment group (OD, n=8), and OVX with DHEA inhibitor group (ODI, n=8) for 8 weeks. [Results] Intestinal calcium accumulation, as well as the rate of absorption, demonstrated no significant differences during the experimental period among investigated groups. The bone mineral density (BMD) of the tibia at the proximal metaphysis was higher in the OD group than that in the OC group (p<0.05); however, BMD of the ODI group showed no significant difference from investigated groups. Furthermore, the BMD of the tibia at the diaphysis did not significantly differ among these groups. [Conclusion] We revealed that DHEA administration does not involve intestinal Ca absorption, although this treatment improves BMD levels in OVX rats. These observations indicate that the effect of DHEA on the bone in postmenopausal women is solely due to its influence on bone metabolism and not intestinal calcium absorption.

• Toxicological Research
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• v.16 no.3
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• pp.201-209
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• 2000

In association with the international validation program to establish a rodent uterotrophic assay, we conducted preliminary uterotrophic assay proposed by GECD using immature female rats. In the present study, oral and subcutaneous routes were chosen to compare the effects of estrogenic com-pounds in the two dosing regimens. The reference compound ethinyl estradiol (EE) and the antagonist ZM189154(ZM) were administered by gavage or subcutaneously (s.c.) to immature female SD rats from 20 to 22 days of age. For each study, sixty-six female rats were randomly assigned to eleven groups: Untreated control, EE 0,0.01, 0.03, 0.1, 0.3, 1.0,3.0 and 10.0 $\mu\textrm{g}$/kg, EE 3.0 $\mu\textrm{g}$/kg(gavage)/0.3 $\mu\textrm{g}$/kg(s.c) & ZM 0.1 mg/kg, and EE 3.0 $\mu\textrm{g}$/kg(gavage)/0.3 $\mu\textrm{g}$/kg (s.c) & ZM 1.0 mg/kg. There were no treatment-related changes in clinical signs, body weights, food consumption, and necropsy findings in any groups of two studies. The wet and blotted uterus weights increased dose-dependently. Histopathological examination revealed that diameter of uterine duct, height of uterine luminal epithelium. and height oj vaginal epithelium increased dose-dependently. The proliferating cell nuclear antigen (PCNA) immunoreactive cells were increased in number dose-dependently. The estrogenic effects observed in the present studies occurred at $\geq$ 0.3 $\mu\textrm{g}$/kg of oral dose and $\geq$ 0.1 $\mu\textrm{g}$/kg of s.c. dose. An antagonistic effect of ZM against EE was found in both uterus weight and histopathological parameters. From the results obtained, it can be concluded that dose-dependence of the uterotrophic assay using EE and ZM was well demonstrated by gavage and subcutaneous administration and that the estrogenic effects of EE by s.c. dose were higher than those by gavage administration. In addition, blotted uterus weight was more sensitive than wet uterus weight and vaginal epithelial height was found to be the most sensitive parameter among the parameters examined.

• Nutrition Research and Practice
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• v.2 no.2
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• pp.68-73
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• 2008

This study was focused on whether or not isoflavones affect the increase in bone mineral density of growing females. Female Sprague-Dawley rats ($60{\pm}5\;g$) were randomly assigned to two groups and provided control diets (control group) or isoflavone-supplemented diet (IF group, 57.8 mg isoflavones/100 g diet) for 9 weeks in growing female rats. Measurements of Bone Mineral Density (BMD) and Bone Mineral Content (BMC) on the experimental animals were executed in the $3^{rd}$, $6^{th}$, $9^{th}$ weeks. In result, there was no significant difference in spine BMD between the isoflavones supplemented group and the control group. But, the IF group tended to have higher BMD than the control group in between 3 and 9 experimental weeks, and the striking difference could be shown in the $6^{th}$ week of feeding. In case of femur BMD, the effects of added isoflavones appeared in the $6^{th}$ week of feeding, and it became intensified in the $9^{th}$ week of feeding to the extent that the BMD in the IF group was significantly higher than that of the control group (p<0.05). In conclusion, isoflavone supplementation increased spine BMD per weight in the $6^{th}$ week of feeding, and affected the increase of femur BMD in the $9^{th}$ week. The result of the experiment implies that it affects positively the formation of spine and femur BMD of growing female rats. The study also suggests that the effects of isoflavone on the pattern of BMD formation might differ from the parts of bones.

• Toxicological Research
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• v.15 no.1
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• pp.9-17
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• 1999

This study was performed to evaluate the subacute toxicity of CJ-50002 (Vibrio Vaccine) in SPF Spraqur-Dawley (SD) rats. Vibrio vaccine was administered orally at a dose level of high (167mg/kg/day), medium (16.7mg/kg/day), and low (16.7mg/kg/day) once a day and repeated fro 4 weeks. Ten males and female rats were assigned to each group. After 4 week administration, no significant dose-dependent changes in body weight, water and food consumption rate or organ weight were noted dependent changes in body weight, water and food consumption rate or organ weight were noted among 4 groups. Urinanalysis, hematology, and serum chemistry, also fail to detect any dose-related change among 4 groups tested. During necropsy and histopathological examination, no specific toxicity related to treated material was found. The result of this study demonstrated that vibrio vaccine when administered orally for 4 weeks at a high dose of 167mg/kg/day, no dose-related toxicity was found in treated make and female rats.

• Toxicological Research
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• v.21 no.2
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• pp.179-186
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• 2005

Dimethylamine (DMA) is a widely used commodity chemical with few toxicity data. Groups of 10 male and female F-344 rats were exposed by inhalation to 0, 5, 10, 20, 40 and 80 ppm of DMA for 6 hrs/day, 5 days/week for 90 days. The changes of body weight, organ weight, hematology, clinical chemistry, and histopathological changes were evaluated after the exposure. As the results, the body weight was significantly decreased at 80 ppm in male and female rats (p<0.05). The absolute lung weight showed no statistically significant changes in any group. In contrast, the relative lung weight significantly increased at 80 ppm in male and female rats (p<0.05). Erythrocytes, mean cell hemoglobin, leukocytes, neutrophil, and platelet numbers were significantly increased in male and female at 40 or 80 ppm of DMA (p<0.05, p<0.01). In addition, the serum values of total protein, urea nitrogen were increased in male and creatine kinase, total protein were increased in female rats at 40 or 80 ppm (p<0.05, p<0.01). Histopathological examinations of the male and female lung samples showed slight hyperplasia and congestion at 80 ppm. Taken together, our study revealed that maximum tolerated dose of DMA would be over 40 ppm.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.207-214
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• 2008

This study was designed to investigate the suitability of the pubertal assay and the enhanced TG 407 as methods for detection of endocrine-mediated effects, especially thyroid function. Male and female Sprague-Dawley rats were gavaged daily with 0, 12.5, 25, 50 mg/kg alachlor in corn oil during 30 days. The effects of alachlor on thyroid gland, the genital organs and thyroid hormone were measured in male and female rats. Dose of alachlor 25, 50 mg/kg/day increased relative weight of testis and thyroid gland in exposed male rats and decreased relative weight of vagina in exposed female rats. Relative weight of thyroid gland was decreased in alachlor 25 mg/kg/day exposed female rats. Dose of alachlor 25, 50 mg/kg/day decreased plasma T4 and testosterone in female rats. Another purpose of this study was to investigate the effects of endocrine disruptors as like thyroid hormone in vitro. Luciferase activity was measured to dectect reaction of test chemicals and thyroid hormone response elements in HeLaTRE cell. Dose of alachlor 1 nM-1000 nM increased 100-134% luciferase activity compared with control.

• Korean Journal of Animal Reproduction
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• v.24 no.2
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• pp.189-197
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• 2000

In this study, we investigated the preventive and therapeutic effects of antler-extract for osteoporosis. Rats were ovariectomized bilaterally and were fed up with Ca- and P-free diet in order to induce osteoporosis. Body weight, organ weight, the weight of femur and bone ash quantity were examined for 5 weeks. We also performed histological and electronical microscopic examinations. 1. After adminstration of female and male antler extract to osteoporosis-induced rats at the doses of 625 and 1250 mg/kg, respectively, the body weights were significantly increased compared with those of normal control group's which was 230.2:t2.3-281.0:t2.5g (p＜0.05). 2. The weights of both right and left femur of osteoporosis-induced rats, administered with female or male antler-extract, little decreased compared with those of normal control group. 3. The bone ash quanties of femur of osteoporosis-induced rats, administered with female or male antler-extract, little decreased compared with those of normal control group. 4. The weights of liver, spleen, and kidney of osteoporosis-induced rats, administered with female or male antler-extract, decreased compared with those of normal control group. 5. Histological and electronic microscopical findings were (1) that in normal control rats the connectional of lacunae appeared well and were without loss of bone mineral, (2) that in ovariectomized rats the connections of lacunae were mostly broken and were with loss of bone mineral compared with those of normal control rats, (3) that in osteoporosis-induced rats, administrated with female or male antler-extract, the shape of lacunae and the connections of them were similar to those of normal control rats. These findings suggest a possible protective and therapeutic effects of female or male antler extract against bone loss in ovariectomized rats.