• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.25-25
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• 2003

어류의 번식활동은 뇌-뇌하수체-생식소로 이어지는 내분비기관이 주로 담당하고 있으며, 그 중에서 뇌하수체에서 만들어지는 생식선자극호르몬 (GTH)은 생식소 발달에 매우 중요한 역할을 한다. 한편, GTH는 생식소에서 생성되는 스테로이드호르몬에 의해 유전자의 발현이 조절된다. 본 연구에서는 산천어 (Oncorhynchus masou)의 GTH 유전자발현에 미치는 estradiol-17$\beta$ (E2)의 영향을 생체내에서 먼저 조사하고, 유전자발현조절의 메카니즘을 구명하기 위하여 에스트로젠 수용체 (ER)의 cDNA를 cloning하였다. 또한 내분비교란물질로 알려져 있으며 에스트로젠 수용체와의 유사결합작용이 알려진 노닐페놀 (NP)의 영향도 아울러 조사하였다. 미성숙 산천어를 E2 및 NP (각각 5 mg/kg 및 10 mg/kg 체중)로 처리하면 72 시간째에 뇌하수체내의 $\beta$-actin mRNA에 비해 GTH (FSH$\beta$, LH$\beta$) mRNA가 상대적으로 증가하는 경향을 나타내었다. 뇌하수체에서 분리한 ER의 기본적인 구조는 DNA결합도메인 (Zf-C4), 호르몬결합도메인 (hormone_rec), 기타 전사활성화도메인으로 구성되어 있었으며 (그림 1), 기존에 보고된 에스트로젠 수용체중에서 무지개송어 및 대서양연어의 ER과 각각 98%, 96%의 높은 상동성이 관찰되었다. 향후, 준비된 ER을 재료로 하여 GTH 유전자발현의 호르몬의존성을 조사할 예정이다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.6
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• pp.753-760
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• 1995

This study was conducted to determine the serum vitellogenin (VTG) concentration changes during the ovulation period in elkhorn sculpin, Alcichthys alcicornis. The results of sepacryl S-300 showed that the molecular weight of VTG could be 380,000. SDS-polyacrylamide gel electrophoresis (SDS-PAGE) analysis may indicate that the purified VTG consists of three subunits with molecular weights of 180,000, 118,000 and 85,000, respectively. Yolk protein purified from the egg extracts was eluted on an equilibrated sephacryl S-300 column, and its molecular weight was estimated 250,000. The precipitation lines of the female serum against the antiserum of the egg extracts were fused completely by immunoelectrophoresis and immunodiffusion analysis. VTG was detected in the serum, and hepatocytes from males injected with $17\beta-estradiol\;(E_2).$ Furthermore, VTG was immunochemically similar to yolk proteins. The concentration of VTG was high before ovulation $(9.80\pm0.81-11.02\pm0.09 mg/ml),$ and then decreased rapidly after ovulation $(less\;than\;6.19\pm0.59 mg/ml).$ This study suggested that VTG was synthesized in the liver by the action of $E_2$ and released to blood, and then incorporated into oocytes.

• Reproductive and Developmental Biology
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• v.35 no.4
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• pp.519-525
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• 2011

Growth hormone (GH) is obligatory for growth and development. But, there is controversy on the GH effect about reproductive processes of sexual differentiation, pubertal maturation, gonadal steroidogenesis, gametogenesis and ovulation. This study was conducted to investigate the effect of GH on estrus, ovulation and embryo implantation. The results obtained were as follows. GH stimulated to increase estrus rate (p<0.05), pregnancy rate (p<0.05), and total fetus number in mice treated for superovulation. Also, the correlation between GH and steroids, E2 and P4, at peri-estrus stage/ peri-ovulation stage/ peri-implantation stage of the superovulation-induced mice was examined. Consequently, GH co-injected with PMSG especially increased P4 level (p<0.05) at peri-estrus stage of superovulationinduced mice. In conclusion, GH co-treatment in superovulation system boosted the rate of estrus, pregnancy and total fetus by increasing progesterone level at peri-estrus stage of superovulation-induced mice.

• The Korean Journal of Zoology
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• v.34 no.3
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• pp.426-431
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• 1991

The present study examines the effect of naloxone, mu-opioid receptor antagonist, on prolactin (PRL) gene expression and secretion induced by estradiol (I) treahent in vivo. Adult rats were ovariectomized (OW) and implanted with Silastic capsules containing either vehicle (oil) or E. Three days later, NAL (2 mg/kg BW) or saline urere injected 30 min prior to sacrifice. To examine PRL secretion in vitro, the pituitaries were incubated in the superfusion system for 3 hrs. Superfusates were collected at 10 min intenrals on ice and subjected to PRL radioimmunoassay. Endogenous release of PRL in OU( + I rats was signifcantlv higher than that in OVX rats (mean $\pm$ SE; 24.5 $\pm$ 3.1 vs 14.5 $\pm$ 2.9 ns/10 min). A single injection of NAL clearly inhibited PRL release in Nitro from pituitaries derived from OW + I rats, but not from OW group. PRL myNA was determined by RNA-blot hybridisation assay with nicktranslated PRL CDNA. E stimulated PRL mRNA about 3 fold over that shown in OW group. Treahent of NAL suppressed the I-stimulated PRL myNA in OVX + I group, but not in OVX group. These data clearly showed that the NAL-induced inhibition of PRL secretion was well correlated with changes in PRL mRNA level and this inhibitory process appears to be mediated in I-dependent manner.

• Animal cells and systems
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• v.14 no.3
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• pp.161-167
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• 2010

This study investigated the estrogenicity of 4-nonylphenol (NP) and diethylstilbestrol (DES) in vitro during oocyte maturation in the marine fish, Tridentiger obscurus, using steroid hormone assays and GVBD assay. Vitellogenic (0.53mm diameter) and fully vitellogenic (0.75mm diameter) oocytes were in vitro exposed to NP (0.045 453.82 nM and DES (0.037 372.62 nM). In vitellogenic oocytes, 45.38 and 453.82nM NP and 3.73 372.62nM DES increas the estradiol-$17{\beta}$ (E2)/testosterone (T) ratio. In fully vitellogenic oocytes, 0.45, 45.38 and 453.82nM NP and 3.73nM DES increased E2/T. In the GVBD assay, 0.45 and 4.54nM NP and 0.037, 3.73 and 37.26nM DES inhibited GVBD. These results suggest that NP and DES have estrogen-agonistic effects in oocyte maturation in T. obscurus. In addition, NP and DES have different sensitivity according to the oocyte developmental stage, and the estrogenagonistic effects of DES were greater than were those of NP.

• Journal of Embryo Transfer
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• v.21 no.4
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• pp.315-322
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• 2006

This study was performed to investigate the physiological effects of bovine follicular fluid (bFF) or anti-inhibin serum (AI) on follicular development in Hanwoo. Saline (0.95%), bFF or AI (total of 40 ml) were administered into the jugular vein in 9 Hanwoo cows. The plasma inhibin, estradiol-17 $\beta$ (E2), and progesterone (P4) levels were measured using RIA or ELISA kit and the number of ovarian follicles was observed by ultrasonography at 72 hr after ovulation. The plasma inhibin level in bFF treatment group was significantly increased and maintained higher level from 102 hr after ovulation compared to that of saline and AI groups (p<0.05). In plasma E2 level, AI treatment group showed significantly higher level from 36 hr to 108 hr after ovulation than that of saline and bFF groups (p<0.05). After that it showed decreasing tendency. The plasma P4 level was increased in control and AI treatment groups at 68 hr after ovulation. However, it was maintained significantly lower level in bFF group from 84 hr to 180 hr compared to that of saline and AI group (p<0.05). As a result of ultrasonography at 72 hr after ovulation, higher number of follicles was shown in AI treatment group compared to bFF groups, although the difference was not statistically significant. Taken together, it can be postulated that a treatment of synthesized AI inhibits the secretion of inhibin, stimulates FSH secretion inhibited by inhibin, and induces follicular development and estrogen secretion. According to these results, a development of ovarian follicle immediately after ovulation is associated closely with inhibin in Hanwoo heifers.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8975-8979
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• 2014

Objective: To explore the possible significance of aromatase P450 in endometrial hyperplasia with a background of polycystic ovary syndrome (PCOS). Methods: Immunohistochemistry was used to determine the expression of aromatase P450 in endometrium of PCOS patients. Semiquantitative analysis of aromatase P450 expression of mRNA and protein level wasalso carried out by real-time quantitative RT-PCR method. After endometrial cells were stimulated by testosterone and letrozole in vitro, the estradiol ($E_2$) level was determined, and the expression of cell aromatase P450 mRNA was assessed. Results: The aromatase P450 mRNA level was increased in endometria of PCOS patients. When endometrial cells were cultured with $10^{-6}M$ testosterone, the $E_2$ level in the culture medium increased. An inhibitory effect on $E_2$ generation and expression of aromatase P450 mRNA was observed when the endometrial cells were treated with $10^{-5}M$ letrozole. Conclusions: There is an increased expression of aromatase P450 in PCOS patient endometrium. Androgen stimulation could enhance the synthesis of aromatase P450 mRNA and the production of $E_2$ in endometrial cells in vitro while letrozole could do the reverse.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.1029-1035
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• 2003

Osteoporosis is recognized as one of the major hormonal deficiency diseases, especially in menopausal women and the elderly. When estrogen is reduced in the body, local factors such as IL-1 $\beta$ and IL-6, which are known to be related with bone resorption, are increased and promote osteoclastogenesis, which is responsible for bone resorption. In the present study, we investigated whether glucosidic isoflavones (Isocal, PIII) extracted from Sophorae fructus affect the proliferation of osteoblasts and prevent osteoclastogenesis in vitro by attenuating upstream cytokines such as IL-1$\beta$ and IL-6 in a human osteoblastic cell line (MG-63) and in a primary osteoblastic culture from SD rat femurs. Interestingly, IL-1$\beta$ and IL-6 mRNA were significantly suppressed in osteoblast-like cells treated with 17$\beta$-estradiol (E2) and PIII when compared to positive control (SDB), and this suppression was more effective at $10^{-8}$% than at the highest concentration of $10^{-4}$%. In addition, these were confirmed in protein levels using ELISA assay. In the cell line, the cells showed that E2 was the most effective in osteoblastic proliferation over the whole range of concentration ($10^{-4}%-10^{-12}$%), even though PIII also showed the second greatest effectiveness at $10^{-8}$%. Nitric oxide (NO) was significantly (p<0.05) upregulated in PIII and E2 over the concentration range $10^{-6}% to 10^{-8}$% when compared to SDB, without showing any dose dependency. In bone marrow primary culture, we found by TRAP assay that PIII effectively suppressed osteoclastogenesis next to E2 in comparison with SDB and culture media (control). In conclusion, these results suggest that local bone-resorbing cytokines can be regulated by PIII at lower concentrations and that, therefore, PIII may preferentially induce anti-osteoporosis response by attenuating osteoclastic differentiation and by upregulating NO.

• Fisheries and Aquatic Sciences
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• v.7 no.1
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• pp.16-22
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• 2004

Plasma steroid hormone levels in the viviparous rockfish (Sebastes schlegeli) were examined in relation to gonadal histology under controlled photoperiods and water temperatures. To investigate those effects in S. schlegeli the photoperiod was maintained at 15L:9D in June and then it was gradually decreased to 9L: 15D in October. It was then gradually increased to 12L:12D in January, followed by 14L:I0D in February. The water temperature was $19-20^{\circ}C$ in July. From August to October, it was from $18^{\circ}C\;to\;12^{\circ}C$. Then, it was dropped to a low of $19-11^{\circ}C$ in November to December and then gradually increased to $14-15^{\circ}C$ in February. In females, both plasma $estradiol-l7\beta\;$ (E2) and testosterone (T) levels from August to February showed a similar pattern in both the treatment and the control groups. In the treatment group, the peaks of plasma E2 and T were observed in November, and the peaks were closely correlated to histological observations. Oocytes contained many yolk globules (final vitellogenic oocytes), and oocytes at the migratory nucleus stage increased in size. Plasma levels of progesterone did not change much throughout the experimental period. However, in the control group, the peaks of E2, T, and progesterone were observed in February. These results indicate that the controlled photoperiod and water temperature accelerated sexual maturity, corresponding to the advancement of plasma E2 and T peaks by approximately 3 months. In males, plasma T levels showed a similar pattern from August to October in the treatment and control groups, though levels in the treatment group were higher than those in the control group. From histological observations, the treatment group copulated one month earlier.

• Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.221-231
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• 2012

The marine medaka Oryzias dancena choriogenin H gene (odChgH) and its mRNA expression during estradiol-$17{\beta}$ (E2) exposure were characterized. At the amino acid level, the choriogenin H protein is predicted to possess the conserved repetitive N-terminal region, as well as zona pellucida (ZP) and Trefoil factor family (TFF) domains. At the genomic level, odChgH has an eight-exon organization with a distribution pattern of transcription factor binding sites in the 5'-upstream region, which is commonly found in other estrogen-responsive genes. The tissue distribution pattern of odChgH mRNA was found to be gender-specific, whereby females showed a higher expression level and wider tissue distribution than did males. During embryonic development, odChgH mRNA was robustly detected from the stage of visceral blood vessel formation. Experimental E2 exposure of males resulted in odChgH mRNA being induced not only in the liver, but also in other several tissues. The E2-mediated induction was fairly dose-dependent. The basal expression levels of hepatic odChgH mRNA were lower in males that were acclimated to 30 ppt salinity than in those acclimated to 0 or 15 ppt salinity. In contrast, the inducibility of odChgH mRNA during E2 exposure was greater in seawater-acclimated fish than in brackish water- or freshwater-acclimated fish.