• Animal cells and systems
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• 제7권3호
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• pp.227-235
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• 2003

Bisphenol A (BPA), nonylphenol (NP), and 4-tert-octylphenol (OP) are known endocrine disrupting chemicals (EDCs) with estrogenic activity in fish. This study compared the effects of BPA, NP and OP on in vitro vitellogenin (VTG) synthesis in primary cultures of hepatocytes of the Chinese minnow Phoxinus oxycephalus. The VTG secreted into the culture medium was measured using enzyme-linked immunosorbent assay (ELISA), which we developed in this study using an antibody prepared from homogenates of Chinese minnow egg. VTG synthesis was induced by estradiol-17$\beta$ ($E_2$) and phenols (BPA, NP and OP) treatment. $E_2$ at concentrations of 10$^{-6}$ M or higher increased VTG levels significantly (P < 0.05). Exposure to 10^5\;M\;BPA\;or\;10^-4$M NP and OPinduced in vitro VTG synthesis (P < 0.01). However, $10^-3$ M BPA, NP or OP did not induce VTG synthesis. These results suggest that SPA has the highest estrogenic potential in Chinese minnow hepatocytes. Tamoxifen, an anti-estrogen, drastically blocked the production of VTG by phenols (BPA, NP and OP) suggesting that phenols (BPA, NP and OP) may act via binding to estrogen receptor (ER) in Chinese minnow hepatocytes.

• 대한수의학회지
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• 제46권1호
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• pp.35-41
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• 2006

Vitellogenin (Vtg), a phospholipoglycoprotein precursor of egg yolk is synthesized and secreted from the liver in response to estrogens in female fish. Vtg is normally undetectable in the blood of male fish, but can be induced by exposure to chemicals possessing estrogenic activity. Thus, the presence of Vtg in blood of male fish can serve as a useful biomarker for assessing previous exposure to estrogenic compounds. In the present study, Vtg was abnormally expressed in Rhynchocypris oxycephalus using estradiol benzoate ($E_2$). As the result, it was found that the level of Vtg in blood from R. oxycephalus was increased by treated quantity of $E_2$ with dose-effect manner. Monoclonal antibodies were generated against Vtg of R. oxycephalus. The hybridoma were screened with an enzyme immunoassay for the production of specific anti-Vtg antibodies. Five positive cell lines with a high specificity were selected. Monoclonal antibodies against vtg of R. oxycephalus that was developed in this study, may be a useful bio-indicator for the detection of estrogenic contamination in the aquatic ecosystem.

• Asian-Australasian Journal of Animal Sciences
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• 제32권9호
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• pp.1355-1362
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• 2019

Objective: S100A7A, a member of the S100 protein family, is involved in various biological processes, including innate immunity, antimicrobial function, and epithelial tumorigenesis. However, the expression and function of S100A7A in the endometrium during the estrous cycle and pregnancy are not well understood in pigs. Therefore, this study determined the expression and regulation of S100A7A at the maternal-conceptus interface in pigs. Methods: We obtained endometrial tissues from pigs throughout the estrous cycle and pregnancy, conceptus tissues during early pregnancy, and chorioallantoic tissues during midto late pregnancy and analyzed the expression of S100A7A in these tissues. We also determined the effects of steroid hormones, estradiol-$17{\beta}$ ($E_2$) and progesterone, and interleukin-$1{\beta}$ (IL1B) on S100A7A expression in endometrial tissues. Results: We found that S100A7A was expressed in the endometrium during the estrous cycle and pregnancy in a pregnancy status- and stage-dependent manner and was localized to endometrial luminal epithelial (LE) and superficial glandular epithelial cells with strong intensity in LE cells on day 12 of pregnancy. Early stage conceptuses and chorioallantoic tissues from day 30 to term pregnancy also expressed S100A7A. The expression of S100A7A was increased by $E_2$ and IL1B in endometrial tissues. Conclusion: S100A7A was expressed at the maternal-conceptus interface at the initiation of implantation in response to conceptus-derived estrogen and IL1B and could be a unique endometrial epithelial marker for conceptus implantation in pigs. These findings provide an important insight into the understanding of conceptus-endometrial interactions for the successful establishment of pregnancy in pigs.

• Animal Bioscience
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• 제36권7호
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• pp.1034-1043
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• 2023

Objective: Two serine protease inhibitors, peptidase inhibitor 3 (PI3) and secretory leukocyte protease inhibitor (SLPI), play important roles in protease inhibition and antimicrobial activity, but their expression, regulation, and function at the maternal-fetal interface in pigs are not fully understood. Therefore, we determined the expression and regulation of PI3 and SLPI in the endometrium throughout the estrous cycle and at the maternal-fetal interface in pigs. Methods: Endometrial tissues during the estrous cycle and pregnancy, conceptus tissues during early pregnancy, and chorioallantoic tissues during mid to late pregnancy were obtained, and the expression of PI3 and SLPI was analyzed. The effects of the steroid hormones estradiol-17β (E2) and progesterone (P4) on the expression of PI3 and SLPI were determined in endometrial explant cultures. Results: PI3 and SLPI were expressed in the endometrium during the estrous cycle and pregnancy, with higher levels during mid to late pregnancy than during the estrous cycle and early pregnancy. Early-stage conceptuses and chorioallantoic tissues during mid to late pregnancy also expressed PI3 and SLPI. PI3 protein and SLPI mRNA were primarily localized to endometrial epithelia. In endometrial explant cultures, the expression of PI3 was induced by increasing doses of P4, and the expression of SLPI was induced by increasing doses of E2 and P4. Conclusion: These results suggest that the PI3 and SLPI expressed in the endometrium and conceptus tissues play an important role in antimicrobial activity for fetal protection against potential pathogens and in blocking protease actions to allow epitheliochorial placenta formation.

• Clinical and Experimental Reproductive Medicine
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• 제21권2호
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• pp.137-147
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• 1994

Controlled ovarian hyperstimulation(COH) for in vitro fertilization and embryo transfer(IVFET) often results in the production of more embryos than can be efficaciously transferred at one time. However, embryo cryopreservation provides a mechanism by which additional embryos can be stored for later thawing and transfer. From November, 1990 to October, 1992, we completed 42 transfer cycles of cryopreserved pronucleus(PN) l-cell embryos using the fixed protocol of hormonal replacement therapy in a physiological manner regardless of individual ovarian function. Artificial endometrial stimulation was performed with only exogenous estradiol and progesterone(E-P) in 36 transfer cycles (Group I) and with gonadotropin-releasing hormone agonist(GnRHa) and exogenous estradiol and progesterone(GEEP) in 6 transfer cycles(Group II ). The results were as follows. 1. The Survival rate of total cryopreserved-thawed embryos was 64.9%(198/305): 64.9% (172/265) in Group I and 65.0% (26/40) in Group II. 2. Total 168 embryos were transferred with an average of 4.7 per ET in Group I and total 26 embryos were transferred with an average of 4.3 per ET in Group II. 3. The pregnancy rate(PR) per cryopreserved-thawed ET and the implantation rate was 33.3 %(14/42) and 6.7%(13/194), respectively. The PRs per cryopreserved-thawed ET were 30.6% (11/36) in Group I and 50.0% (3/6) in Group II without significant difference. 4. The take home baby rate was 11.1%(4/36) in Group I and 33.3% (2/6) in Group II.

• 한국어류학회지
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• 제12권1호
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• pp.71-84
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• 2000

1997년 7월부터 1999년 6월까지 2년간 제주도 남부해역인 중문 하예동 연안에서 매월 채집한 말쥐치, Thamnaconus modestus의 생식주기를 조직학적인 방법으로 연구하였다. 암 수컷의 GSI 변화에 있어서 암컷은 5월, 수컷은 6월에 년 중 최고값을 보였다. 생식주기는 암컷인 경우 성장기 3~4월, 성숙기 4~5월, 산란기 5~6월, 퇴화 및 휴지기 7~2월로 구분되었고, 수컷인 경우 성장기 1~3월, 성숙기 4~5월, 방정기 5~6월, 퇴화 벚 휴지기 7~12월로 구분할 수 있었다. 산란기간 동안 말쥐치 암컷을 대상으로 이들의 산란주기 및 산란횟수를 알아보기 위해 생식소 발달상을 조직학적인 방법으로 관찰하고 성 steroid 호르몬인 estradiol-$17{\beta}$ ($E_2$)와 testosterone (T)의 혈중 농도를 RIA 검사를 통하여 조사한 결과 말쥐치는 비동시발달형에 속하는 어종으로 산란기간내 적어도 2 회 이상 산란을 하는 다회산란종으로 추정되며, $E_2$와 T의 혈중 농도 변화는 난모세포의 성숙과 GSI 변동에 거의 상동적으로 변화하고 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1775-1779
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• 2005

Seventy-two crossbred gilts of approximately 33 kg initial weight were used in this study. The gilts were randomly assigned into three groups. The three dietary treatments were basal diet only (control group), basal diet+10 mg/kg lead, and basal diet+10 mg/kg lead+0.5% particulate montmorillonite (PM). The results showed that the addition of lead to the diet decreased significantly the body weight and feed efficiency, but PM could restore body weight and feed efficiency of gilts compared to the Pb exposure group. There were no significant differences in weights of ovaries and uteri with addition of either lead or PM to the diet. Supplementing the lead in the diet of gilts also significantly increased the concentration of lead in blood, decreased circulating lutenizing hormone (LH) and estradiol (E$_2$) levels in serum, the addition of PM to the diet effectively adsorbed and lowered lead concentration in the blood. These data suggested that lead disrupts the signals between the hypothalamus and pituitary gland in gilts, and possibly suppressed the secretion of relative growth hormone and sex hormone. On the other hand, PM may ameliorate Pb toxicity in pigs.

• 한국환경보건학회지
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• 제33권6호
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• pp.513-516
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• 2007

This investigation was intended to find out the estrogenic effect of chlortetracycline (CTC) on vitellogenin induction in adult male Japanese medaka (Oryzias latipes). Vitellogenin (Vtg) produced in male fish has been used to as one of a biomarker of endocrine disrupters. The positive control was $17{\beta}-estradiol$ (E2) that induced Vtg in male fish. As a result, male and female fish were exposed to 0.1, 1, 10 and 100 ppm of CTC. Western blot results showed approximately 205 kDa, that is similar to myosin at high molecular weight range Sigma maker. Vtg band was showed fainted to 10 and 100ppm for chlortetracycline. Vtg concentration of CTC was qunatified by total protein quantification and ELISA. Exposure of the male fish to CTC of 0.1, 1, 10 and 100 ppm produced Vtg concentrations of 0.24, 0.12, 7.61 and 40.02%o, respectively, that value was elevated than control male fish (0.14%o). CTC exerted as a Vtg inducer in male fish from 10 ppm, but it was a reducer in female fish from 0.1 ppm level. The results say that vitellogenin induction patterns alter in male medaka treated with CTC, and that CTC may caused endocrine disruption in fish.

• 한국수산과학회지
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• 제33권4호
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• pp.302-306
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• 2000

양식 잠재력이 높은 어종인 쥐노래미 (Hexagrammos otakii)의 번식생리에 관한 기초 자료를 얻고자 쥐노래미의 생식주기와 함께 혈청의 성 스테로이드호르몬의 변화에 관하여 연구하였다. GSI는 암컷과 수컷에서 3월부터 8월까지 유의한 변화를 보이지 않다가 9월부터 상승하기 시작하여 1월에 최고값을 보였다. 암컷의 혈중$E_2$의 수준은 12월에 가장 높은 값을 보였으며 1월이 되면 낮아지기 시작하여 8월까지 낮은 수준을 유지하다가 9월부터 다시 상승하기 시작하였다. 암컷에서의 혈중 T 변화도 $E_2$,와 유사한 경향이었다. 암컷 혈중의 $17{\alpha}20{\beta}-OHP$ 변화를 보면 1월에 연중 최고값을 나타내었다. 그후 2월부터 급격하게 떨어져 7월까지 낮은 값이 유지되었고 8월에 약간 상승하였다. 수컷에서 T의 혈중 수준은 12월에 최고값을 나타내었으나 1월부터 급격히 하강하였다가 7월부터 다시 상숭하기 시작하였다. 한편 수컷 혈중 $17{\alpha}20{\beta}-OHP$의 수준은 전체적으로 암컷의 $17{\alpha}20{\beta}-OHP$ 변화 경향과 유사하였다.

• 한국동물학회지
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• 제39권3호
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• pp.273-281
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• 1996

본인 등은 참개구리를 이용하여 여포의 스테로이드 생성에 관한 two-cell type model을 제시한바 있다. 본 연구에서는 이 model이 북방산 개구리 (R. dybowskii)에도 적용 되는지와 협막세포층에 minor pathway(P 5$\longrightarrow$17$\alpha$-OHP$_4$)가 있는지의 여부를 조사하였다. 이를 위하여 북방산 개구리 난소로부터 intact follicles (IFs), granulosa cell enclosed-oocytes (GcEOs), theca/epithelium (THEP) layers 및 난구세포가 포함되어 있지 않은 순수한 theca/epithelium (P-THEP) layers를 미세해부기술로 분리해 내었다. 이들 여포 조직들은 전구 스테로이드나 개구리 뇌ㅏ수체추출물(FPH)이 포함되어 있는 배양액에서 6시간 배양한 후, 각 여포조직 의해 전환된 산물스테로이드의 양을 방사면역측정법으로 조사하였다.외부에서 첨가된 P 5와 P$_4$는 GcEOs와 IFs에 의하여 효율적으로 P$_4$혹은 17 $\alpha$-OHP$_4$로 전환되었으나 THEP에 의해서는 전환되지 않았다. 더욱이 순수한 협막층(P-THEP)에 의해서는 전환이 거의 이루어지지 않았다. 17 $\alpha$-OHP$_4$및 testosterone 역시 GCEOs와 IFs에 의해서 estradiol (E$_2$) 및 androstenedione (AD)으로 각각 전환되었으나 THEP에 위해서는 정환되지 않았다. 반면에, AD는 THEP과 IFs에 의해서만 T로 전환되어졌으며, AD를 제외한 다른 전구스테로이드들은 THEP 의해서도 T로 전환되지 못했다. 이러한 결과들은 P$_4$, 17 $\alpha$-OHP$_4$AD 및 E$_2$는 주로 난구세포에서 생성되고, T는 주로 협막세포에서 생성되며 T나 E$_2$의 효율적인 생성에 이들 두 세포의 협조가 필요하다는 것을 말해준다. 이는 참개구리에서 제시한 two-cell type model이 북방산개구리 여포의 스테로이드 생성과정에도 적용되며 협막 세포층에는 minor pathway ( P5 to 17$\alpha$-OHP$_4$)가 존재하지 않음을 또한 보여주고 있다.