• Journal of Nutrition and Health
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• 제30권10호
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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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• 제17권4호
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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.

• 생약학회지
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• 제40권2호
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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.

• 운동영양학회지
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• 제24권4호
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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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• 제16권3호
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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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• 제2권2호
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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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• 제15권1호
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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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• 제21권2호
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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.

• 농약과학회지
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• 제12권3호
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• pp.207-214
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• 2008

내분비장애 추정물질의 분류를 위해 많은 시험법이 연구되고 있는데 추후 내분비장애 추정물질로 분류된 기등록 농약에 대한 자료요구 또는 신규 등록농약에 대한 등록기준의 추가 등을 고려하여 OECD와 EPA에서 권장하는 시험법을 확립하고자 본 연구를 수행하였다. 시험약제를 30일간 경구 투여하여 조사한 결과, alachlor 투여 수컷에서 25 mg/kg/day, 50 mg/kg/day에서 고환과 갑성선의 중량이 증가하였다. Alachlor 투여 암컷에서는 질의 중량이 25, 50 mg/kg/day에서 감소하였고 25 mg/kg/day에서 갑상선의 중량이 감소하였다. Alachlor 투여 암컷 25, 50 mg/kg/day에서 주요 갑상선 호르몬인 T4와 성호르몬 testosterone이 감소하였다. 따라서 pubertal assay 결과 alachlor는 갑상선 호르몬성 영향이 의심되었다. 시험세포를 이용한 시험 결과, 시험약제를 1 nM에서 1000 nM까지 처리하였을 때 음성대조군과 비교하여 alachlor는 100-134%의 갑상선 호르몬성 영향을 나타내었다. 따라서 세포를 이용한 시험에서는 alachlor에 의한 갑상선 호르몬성 영향이 나타나는 것으로 판단되었다. 항갑상선 호르몬성 영향 시험에서는 시험약제 100 nM과 T4의 혼합 처리시 alachlor는 항갑상선 호르몬성 영향은 나타나지 않았다.

• 한국가축번식학회지
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• 제24권2호
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• pp.189-197
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• 2000

본 연구는 골다공증유발 rat에 녹용추출물의 투여가 예방 및 치료효과에 미치는 영향을 구명하고자, 양측 난소를 적출한 후 골다공증이 유발된 rat에 암, 수녹용 추출물 525, 1,250 mg/kg을 투여했을 때 체중, 대퇴골의 중량, 장기중량, 골회분량의 측정 및 조직학적, 전자현미경적 검사 등을 실시하였다. 1. 골다공증유발 rat에 암, 수녹용 추출물을 투여했을 때 체중은 정상대조군에 비하여 유의한 증가를 나타냈다 (p＜0.05). 2. 골다공증유발 rat에 암, 수녹용 추출물을 투여했을 때 우측, 좌측의 femur 중량은 정상대조군에 비하여 감소하였다. 3. 골다공증유발 rat에 암, 수녹용 추출물을 투여했을 때 골회분량은 정상대조군에 비하여 약간 감소된 치를 나타냈으나 유의성은 인정되지 않았다. 4. 골다공증유발 rat에 암, 수녹용 추출물을 투여했을 때 간과 비장 및 신장의 각각 정상대조군에 비하여 감소된 치를 나타냈다. 5. 골다공증유발 rat에 암, 수녹용 추출물을 투여했을 때 조직학적 및 전자현미경적 소견은 정상대조군에서는 소주골간의 연결이 비교적 잘 유지되어 있고 골소실을 발견할 수 없었으나 난소적출군은 정상군에 비하여 소주골이 가늘어졌거나 소주골간 연결부분의 대다수가 끊어져 골양이 많이 소실되었음이 관찰되었으며, 녹용처리군에서는 소주골의 형태가 굵고 연결부분이 잘 유지되어 정상군과 유사한 소견이 관찰되었다. 위의 결과들에서 암, 수녹용 추출액은 난소제거후의 골소설을 억제하므로 골다공증의 예방과 치료에 효과가 있는 것으로 판단된다.