• Asian-Australasian Journal of Animal Sciences
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• 제27권4호
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• pp.479-487
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• 2014

Leptin plays an important role in energy homeostasis and reproductive function in fish, especially in reproduction. Migrating fish, such as salmonoids, are affected by external environmental factors, and salinity changes are a particularly important influence on spawning migrations. The aim of this study was to test whether changes in salinity affect the expression of leptin, estrogen receptors (ERs), and vitellogenin (VTG) in chum salmon (Oncorhynchus keta). The expression and activity of leptin, the expression of ERs and VTG, and the levels of estradiol-$17{\beta}$ and cortisol increased after the fish were transferred to FW, demonstrating that changes in salinity stimulate the HPG axis in migrating female chum salmon. These findings reveal details about the role of elevated leptin levels and sex steroid hormones in stimulating sexual maturation and reproduction in response to salinity changes in chum salmon.

• 한국수정란이식학회지
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• 제30권2호
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• pp.83-89
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• 2015

The sexual maturation occurred by the changes of steroid hormones was known to sex-dependently and/or age-dependently regulate the lipid metabolism in various animal species. Our current study demonstrates that lipid and its functional fatty acids can be changed depending on the status of sexual maturation. Of the functional fatty acids, ${\gamma}$-linolenic acid (GLA; 18:3n-6) is an important factor for maintaining human health. The purpose of our study was to investigate the level of GLA in mice with different stages of sexual maturation. To this end, the longissimus muscle (LM) of immature (3-week-old) and mature (7-week-old) female mice was analysed for the fatty acid composition by gas chromatography. Furthermore, both gene and protein level of ${\Delta}6$ desaturase (FADS2) which is involved in GLA metabolism by real time PCR and Western blotting, respectively. Mature females showed greater (P<0.05) serum $17{\beta}$-estradiol (E2) level and LM GLA contents than immature group. The mRNA and protein levels of FADS2, which converts precursor linoleic acid into GLA, were higher (P<0.05) in mature female mice than in immature mice. In conclusion, these results show that sexual maturation of female mice induces GLA and FADS2 contents in LM.

• Biomolecules & Therapeutics
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• 제16권3호
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• pp.293-298
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• 2008

Cirsium japonicum water extracts has been used to treat vascular related diseases. We have previously reported that Cirsium japonicum extracts activated estrogen receptors. It is widely known that estrogen increases the high density lipoprotein cholesterol and decrease the low density lipoprotein cholesterol on the lipid profile. But effects of Cirsium japonicum on lipid profile are not reported yet. Therefore, we have studied the effects of Cirsium japonicum on the lipid content in ovariectomized rats. Thirty Sprague-Dawley (SD) rats of $210{\pm}20\;g$ were studied for 10 weeks. The rats were divided into five groups; (I) sham, no ovariectomized rats plus olive oil, (II) ovariectomized rats plus olive oil, (III) ovariectomized rats plus 0.5 mg/kg $17{\beta}$-estradiol (E2) in olive oil, (IV) ovariectomized rats plus 0.5 mg/kg Cirsium japonicum in olive oil, and (V) ovariectomized rats plus 5 mg/kg Cirsium japonicum in olive oil. Treatment with Cirsium japonicum or E2 induced significant reduction in total cholesterol, low density lipoprotein cholesterol/total cholesterol, total cholesterol/high density lipoprotein cholesterol and low density lipoprotein cholesterol/high density lipoprotein cholesterol compared to control group as well as increase in uterine weight. However, changes in triglycerides levels were different. Our results suggest that Cirsium japonicum is functionally similar to E2 in vivo as well as in vitro.

• 한국발생생물학회지:발생과생식
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• 제1권1호
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• pp.25-28
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• 1997

The present study was conducted to determine the effect of recombinant human follicle stimulating hormone (rhFSH) on the estrogen synthesis by human fetal ovarian tissues. Fetal ovaries were 18-19 weeks old (18 wks:n=1, 19 wks:n=2). One case of 19-week-old fetal ovaries were obtained from anencephalic fetus. Obtained ovarieswere cleaned and diced around $600\mu\textrm{m}$ pieces, and cultured in the sandwich agar bed system for 21-23 days. Estrone ($E_{1}$) and estradiol-17 $\beta$($E_{2}$) in the medium was measured by radioimmunoassay. Amount of $E_{2}$ synthesis was greater than $E_{1}$ in both normal cases. In contrast, fetal ovaries from anencephalic fetus did not produce neither $E_{1}$ nor $E_{2}$ in the presence or absence of rhFSH. Results suggest that the fetal ovaries have a capacity of estrogen production at 18-19 weeks of gestation Existence of FSH receptor is also supposed. Different results by anecephalic fetal ovaries suggest the difference in the development between normal and anencephalic fetal ovaries.

• 한국가축번식학회지
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• 제9권2호
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• pp.113-123
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• 1985

1. The weights of ovary and uternus in the all treated groups were lighter than those in control group showing significantly differences from 4 weeks after treatment. The significant was not recognized between PTU and Thx. groups, and Thyro. and control groups. 2. In the histological changes of ovary, follicles were disa, pp.ared and alignment of membrana granulosa disnitergration in cell change were serious in Thx. and PTU groups and slight in Thyro. group. 3. In the histological changes of uterus, endometrial epithelium and lamina propria were atrophied from 3 weeks after treatment in Thx. group, from 4 weeks in PTU groups and from 5 weeks in Thyro. group. Muscular layers were atrophied with time elapse in the all treated groups. 4. The changes of the concentrations of serum progesterone at all observation times in Thx. and PTU groups were significantly decreased in comparison with those in control group. While those in Thyro. group were significantly increased in comparison with those in control group. 5. The concentration of serum estradiol-17$\beta$ at all observation times in all experimental groups were below 27.2pg/ml. Therefore, we did not detect any changes of the concentrations.

• 한국수정란이식학회지
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• 제11권3호
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• pp.241-248
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• 1996

This study was conducted to improve the production efficiency of in vitro produced (IVP) embryos in Korean Native cows. The optimal conditions and procedures for in vitro maturation(IVM), in vitro fertilization(IVF) and in vitro culture(IVC) of bovine follicular oocytes and IVP embryos were evaluated. Immature follicular oocytes were collected fiom the follicles of bovine ovaries obtained from abattoirs. The oocytes of Grade I and II for IVM were cocultured with monolayered bovine oviductal epithelial cells(BOEG) or granulosa cells in TCM-199 solution supplemented with follicle stimulating hormone, lutenizing hormone, estradiol-17$\beta$ and heat inactivated fetal calf serum at 39$^{\circ}C$ under 5% $CO_2$ in air for 14 to 24 hours. Most of the oocytes(93%) matured to metaphase II in 24 hours. The cocultured IVM oocytes were fertilized in vitro at significantly(P<0.05) higher rate with BOEC(83.8%) and with granulosa cells(84.6%) than the non-cocultured IVM oocytes(73.6%). The IVM-IVF embryos developed to morula and blastocyst at significantly(P<0.05) higher rate in coculture with BOEC(41.2%) than with granulosa cells(23.1%) or conditioned medium(23.4%).

• 대한한의학회지
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• 제37권3호
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• pp.39-46
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• 2016

Objectives: The present study aimed at investigating the effects of Schisandrae Fructus (SF) on menopause symptoms in ovariectomized mice. Methods: 6 weeks old female mice were ovariectomized (OVX), and the OVX mice were fed with a three doses of SF (25, 100, and 400 mg/kg, respectively) or $17{\beta}$-estradiol (E2, 0.5 mg/kg) 3 times a week for 6 weeks. Body weight was measured at every week and uterus weight was also measured at the end of experiment. Lipids and osteocalcin levels in serum were analyzed. Results: The uterine weight was not changed in SF treated group, while E2 intake increased the reduced uterine weight by OVX. Although Body weight was increased since two weeks after ovariectomy compared with sham operated group, there was no change in SF or E2 treated group compared with OVX. But LDL was significantly reduced in SF (400 mg/kg) or E2 fed mice and SF or E2 treatment decreased enhanced osteocalcin level by OVX. Conclusion: These results indicated that SF would be effective in the improvement of LDL level and osteoporosis on menopause.

• The Korean Journal of Physiology and Pharmacology
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• 제10권3호
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• pp.123-129
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• 2006

In several experimental models, estrogens protect neurons against ischemic insults. However, the recent clinical studies of hormone replacement showed negative results to prevent stroke. Therefore, optimal models to study estrogen replacement for neuroprotection are needed before its clinical ap-plication. Organotypic hippocampal slice under oxygen-glucose deprivation (OGD) has been established as a model of cerebral ischemia and has advantages to study drug effects. We investigated whether estrogen protected CAI neurons and affected activation of Akt (pAkt) in CAI region under OGD. Thus, rat hippocampal slices on day 7 of culture were treated with $17-{\beta}$ estradiol (E, 1 nM) for 7 days before 30 min OGD, and cell death of CAI neurons was quantified by propidium iodide (PI) staining and expression of pAkt was studied by Western blot and immunofluorescence. PI intensity in slices treated with E was significantly reduced 72 hour after OGD compared to that of non-treated slices (p < 0.05). E pretreatment also increased the expression of pAkt 72 hour after OGD compared to that of no treatment (p<0.01). These data suggest that estrogen pretreatment may rescue neurons from ischemic insults through the activation of Akt and also indicate that our model would be a useful alternative method to study the mechanisms and effects of estrogen replacement treatment for neuroprotection.

• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.24-29
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• 1998

Effect of extracellular calcium in vitellogenin (VTG) production in response to estradiol-17 $\beta$ $(E_2,\;2\times10^{-6}M)$ was examined in primary hepatocyte culture of rainbow trout, Onchorhynchus mykiss. Total calcium in estrogenized sera significantly increased, compared with the control, while diffusible calcium was insignificant. However, diffusible calcium in the incubation medium with $E_2$ was significantly reduced, compared with the control. The uptake of extracellular calcium by cultured hepatocytes signifIcantly increased 90 min after $E_2$ addition. Moreover, the accumulation of intracellular calcium increased in the cultures with $E_2$, regardless of the calcium concentrations in the incubation media. In addition, $E_2-primed $ VTG production was significantly decreased by withdrawal of E_2$ from the incubation medium. Moreover, VTG production by $E_2-primed$ hepatocytes was reduced by removing calcium from the incubation medium with or without $E_2$. These results suggest that the entry of extracellular calcium into the cytoplasm is an important step for VTG production in primary hepatocyte cultures in rainbow trout.

• Fisheries and Aquatic Sciences
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• 제5권4호
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• pp.251-257
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• 2002

Effects of bisphenol-A (BPA) on vitellogenin (VTG) synthesis and estrogen-estrogen receptor $(E_2- ER)$ binding activity were examined in primary hepatocyte cultures of rainbow trout, Oncorhynchus mykiss. Hepatocytes were precultured for 2 days and then $estradiol-17\beta\;(E_2,\;2\times10^{-6}M)\;BPA\;(10^{-5}-10^{-8}M)$ and/or 4-hydroxy-tamoxifen $(4-OHT,\;10^{-6} M)$ were simultaneously added to the incubation medium. Hepatocytes were cultured for 5 more days and then spent medium was analyzed by SDS-PAGE for VTG production. The addition of BPA to the incubation medium had no effect on the viability of hepatocytes in the culture. On the other hand, BPA increased VTG production in a concentration-dependent way and a significant increment occurred at BPA concentrations greater than $10^{-6}$M. Although VTG was increased by the addition of $E_2\;(2\times10^{-6}\;M)\;or\;BPA\;(10^{-5}M)$, its were reduced by a simultaneous 4-OHT $(10^{-6}\;M)$ addition. BPA inhibited $E_2-human$ ER binding activity by $72\%$ at $10^{-5}$ M of BPA. These results suggested that BPA induced VTG synthesis by BPA-ER binding activity in the hepatocyte of rainbow trout.