• Journal of Embryo Transfer
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• v.4 no.1
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• pp.46-55
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• 1989

The effects of an antiprogesterone (RU 486) and an antiestrogen (tamoxifen) on ovulatory response and oocyte morphology were examined in pregnant mare serum gonadotropin (PMSG)-primed immatare female rats (28 days of age): a comparison has been made on two different regirnens primed with a "control" dose (4 IU) and a "superovulatory" dose (40 IU) of PMSG. Females for control control regimen received three consecutive injections of lmg RU486, lmg tamoxifen, or vehicle at 24, 36 and 48hr, and were killed at 72l'r after PMSG. Animals for superovalatory regimen received lmg RU486, 2.5mg tamoxifen, or vehicle fouowlag the injection schedule comparable to control regimen, and were killed at 60 and 72hr after PMSG. Compared to vehicle group, there was a significant reduction in ovulatory response as judged by the proportion of rats ovulating andi or by the mean number of oocytes per rat for each treatment of RU486 and tamoxifen in both regimens. The activity of tamoxifen in inhibiting the ovulatory response was greater in control, but less in superovulatory regimen than that of RU486 based on the dose employed for each antisteroid. In both regimens, RU 486 did not have any effect 6n the changes in the proportion of degenerate oocytes as well as ovarian weight, well tamoxifen treatment resulted in a marked promotion of oocyte degeneration as well as a great reduction in ovarian weight, compared to each parameter of vehicle group. RU486 treatment in each regimen did not alter the serum levels of any steroid hormones observed. Howerver, tamoxifen treatment was associated with significant increases in serum 17$\beta$-estradiol and decreases in progesterone in both regimens; also significant increases in androgens in superovulatory regimen. The results illustrate the relative inhibitory activity of RU486 and tamoxifen indicating major steroid hormone involved in PMSG-induced ovulation: 17$\beta$-estradiol for control and progesterone for superovulatory regimen. It also appears that tamoxifen-associated elevation of circulating 17$\beta$-estradiol andi or androgens could be in part, a contributing factor to the promotion of oocyte degeneration presumably by producing a hostile oviductal environment after ovulation.ent after ovulation.

• Korean Journal of Veterinary Service
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• v.26 no.2
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• pp.151-156
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• 2003

This study was carried out to get a fundamental information for improvement of reproductive performance in gilt. We investigated the effects of breeds on body weight, age, body length, wither's height, girth and backfat thickness, and the serum concentrations of estradiol-17${\beta}$, cortisol and progesterone at first estrus and mating of gilts. A total of 47 gilts of Duroc, Landrace and Yorkshire, produced at Livestock Experiment Station, Chungnam livestock sanitation research institute from 2000 through 2002, were used for this experiment. Body weight, age and girth of Duroc at frist estrus and mating were higher than those of Landrace and Yorkshire. There were no differences on body length among the three breeds at frist and mating. Wither's height of Duroc and Yorkshire at first estrus and mating was higher than that of Landrace. Backfat thickness of Yorkshire was thinnest among the three breeds at first estrus, but there were no differences on backfat thickness among the three breeds at first mating. Serum estradiol-17${\beta}$ concentration of Landrace(45.0 pg/ml) at first estrus was higher than that of Yorkshire(27.4 pg/ml) and Duroc(21.8 pg/ml), but there were no differences on estradiol-17${\beta}$ concentration (from 18.5 to 31.9 pg/ml) among the three breeds at first mating. Serum cortisol concentration of Duroc at first esturs and mating was higher than that of Landrace and Yorkshire. There were no differences on serum progesterone concentration among the three breeds at first estrus and mating of gilt.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.67-73
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• 1999

The insulin-like growth factor (IGF)s are believed to one of several growth factors that play an adjunctive role in ovarian follicular development. These factors circulate bound to a family of IGF-binding protein (IGFBP)s. It is known that circulating IGFBPs are involved in the transport of IGFs to tissues and modulate IGFs actions at local tissue. The purposes of this study were to evaluate changes in serum IGFBPs profiles during normal ovulatory menstrual cylce and to compare serum IGFBPs profiles in periovulatory phase of between normal ovulatory menstrual cylce and controlled hyperstimulated cycle. Fasting blood samples were obtained from 15 normal healthy women throughout normal ovulatory menstural cyle and on the day of aspiration of oocyte from 10 patients undergoing ovarian hyperstimuation for in vito fertilization-embryo transfer. Serum IGFBP-1 - IGFBP-4 were measured by western ligand blot and immunoprecipitation. Serum $17{\beta}$-estradiol was determined by radioimmunoassay. Type and molecular weight of serum IGFBP did not changed during normal ovulatory menstural cycle. No significant variation in the relative proportion and level of each IGFBP was found throughout normal ovulatory menstural cyle. Also, the relative proportion and level of each IGFBP did not correlated with serum $17{\beta}$-estradiol level. There was no significant difference in the relative proportion and level of each serum IGFBP between on the day of ovulation in normal ovulatory menstrual cylce and on the day of aspiration of oocyte in controlled hyperstimulated cycle. Our data indicate that IGFBPs have regulatory functions in ovary through an paracrine and autocrine rather than endocrine mechanism during normal ovulatory menstural cycle.

• Journal of Life Science
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• v.13 no.6
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• pp.799-804
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• 2003

In order to verify the occurrence of an estrogenic compound in natural products, the estrogenic activity was measured using an in vitro detection system. For this system, human breast cancer cell line MCF7 was transfected using an estrogen responsive CAT reporter plasmid. Estrogenic activities of photosynthetic algae spirulina and sea lettuce were evaluated using this system. Estrogenic activities of a $500\mug/ml\; and\; 50 \mug/ml$ ethanol extracts of spirulina were as much as that of $10^{-8}$M standard solution (17$\beta$-estradiol) and activity of $5\mug/ml$ ethanol extract of spirulina was as much as that of $10^{-10}$ M standard solution. However, no significant estrogenic activity was observed using sea lettuce extract. Estrogenic activities of marine animals, such as star fish and shrimp, were also evaluated using this system, however, no significant estrogenic activity was observed in these extracts. In this result, it is confirmed that spirulina extract possesses estrogenic compound.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.5
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• pp.261-267
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• 2002

The aim of the present study was to investigate the interaction of $estradiol-17{\beta}-bovine$ serum albumin $(E_2-BSA)$ and calcitropic hormones, such as parathyroid hormone, calcitonin, and vitamin D, in regulation of $Ca^{2+}$ uptake in primary cultured renal proximal tubule cells. Statistically significant increase in $Ca^{2+}$ uptake was found from 2 hours after $(E_2-BSA)\;(10^{-9}\;M)$ treatment, while $estradiol-17{\beta}\;(10^{-9}\;M)$ did not affect. Treatment of the cells with $(E_2-BSA)\;(10^{-9}\;M)$ together with parathyroid hormone (PTH) $(10^{-8}\;M),$ vitamin D $(10^{-8}\;M),$ or calcitonin $(10^{-8}\;M)$ significantly stimulated $Ca^{2+}$ uptake by 32.50%, 29.30%, or 27.75%, respectively, compared with the control. However, calcitropic hormones did not exhibit any synergistic effect on the E2-BSA-induced stimulation. $E_2-BSA$ significantly increased cAMP generation and PKC activity. The stimulatory effect of cotreatment of $E_2-BSA$ and PTH or vitamin D was blocked by SQ22536 (an adenylate cyclase inhibitor) and staurosporine (a PKC inhibitor), but the effect of cotreatment of $E_2-BSA$ and calcitonin was not blocked. Furthermore, 8-Br-cAMP and TPA (an artificial PKC promoter) increased $Ca^{2+}$ uptake by 25.51% and 16.47%, respectively, compared with the control. In conclusion, $E_2-BSA$ combined with calcitropic hormones regulated $Ca^{2+}$ uptake partially via cAMP and PKC-dependent mechanisms in renal proximal tubule cells.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.59-59
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• 2003

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.209-212
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• 2007

To evaluate the estrogenic activities of di-ethyl hexyl phthalate (DEHP) and di-butyl phthalate (DBP), two phthalates known as endocrine disrupters, we used MCF-7 human breast cancer cell line. As results, DBP and DEHP had estrogenic effects. In brief, the concentration of maximal MCF-7 cell proliferation was $10^{-7}M\;and\;10^{-8}M$ for DEHP and DBP, respectively. The ratio of maximal cell yield of the test compounds to that of $17{\beta}-estradiol$ was 87.5% for DEHP and 73.4% for DBP. In summary, both DEHP and DBP had cell proliferation potencies in the MCF-7 cell. Potencies ranged from approximately 10 to 100 times less than 17beta-estradiol. DBP was stronger than DEHP in the concentration of maximal efficacy. However, DEHP was stronger than DBP in the MCF-7 cell proliferation. Results from this study suggested that DEHP and DBP may play an important role in the estrogenic activity. Therefore, it is suggested that DEHP and DBP are estrogenic.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.173-179
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• 2000

Effects of Estradiol-$17\beta(E_2)$ and 2, 4-dichlorophenoxy acetic acid (2, 4-D) on vitellogenin(VTG) production were investigated in primary hepatocyte culture of olive flounder, Paralichthys olivaceus. Highest survival rate of hepatocyte were observed at $27^{\circ}C$, which markedly declined equal to 50% of those of $15^{\circ}C$. Vitellogenin production peaked at the concentration of $10^{-6}M\;E_2$. No effect was observed on VTG production at various concentrations of 2, 4-D. However, a low concentration of 2, 4-D (ie, $10^{-8}M$) only appeared increased VTG production. $E_2$ or $10^{-8}M$ 2, 4-D-primed VTG production was markedly inhibited by the addition of $10^{-6}M$ tamoxifen to the culture medium(P<0.01). Inhibition was not affected by combinational treatment with $10^{-6}M$ $E_2$ and $10^{-6}M$ 2, 4-D. These results from the current investigation suggest that 2, 4-D mimics $E_2$, but the mechanism of reaction in inducing the $E_2$ receptor are different in VTG production in oliver flounder hepatocytes.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.141-144
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• 2002

Environmental estrogens are natural or synthetic substances present in the aquatic environment, especially in effluent from sewage treatment. However, the adverse effects of these estrogenic substances on fish reproduction are unknown. Di-2-ethylhexyl phthalate (DEHP) is the most common phthalate, which Ps used as a plasticizer in polyvinylchloride (PVC), and it is widespread in the environment and has been found in aquatic organisms and sediments. Therefore, juvenile common carps (Cyprinus carpio) were exposed to nominal concentrations of 17$\beta$-estradiol (E2) (0.5, 5, 50 $\mu\textrm{g}$/L) and DEHP (10, 100, 500 $\mu\textrm{g}$/L) for 21 days, to determine the adverse reproductive effects of these compounds on plasma vitellogenin (VTG) induction, sex steroid level, and gonad weight. Electrophoresis (SDS-PAGE) revealed that much of VTG was induced in fish exposed to 5 and 50 E$_2$ $\mu\textrm{g}$/L, but none of DEHP exposure showed induction. Enzyme-linked immunosorbent assay (ELISA) revealed that VTG was significantly induced in fish exposed to 5 and 50 E$_2$ $\mu\textrm{g}$/L, and combination of 50 E$_2$ $\mu\textrm{g}$/L with 10 and 500 DEHP $\mu\textrm{g}$/L, but none of DEHP exposure showed induction. Analysis of sex steroid levels in some fish revealed that testosterone (T) was detected in both male and female fish of the control and DEHP exposures, but none of fish exposed to 22 concentrations had detectable testosterone level. On the other hand, E$_2$ exposure induced 17$\beta$-estradiol in plasma of male fish, but there was no induction of 17$\beta$-estradiol in plasma of male fish exposed to DEHP. Comparison of gonadosomatic index (GSI) revealed that maximal E$_2$ exposure inhibited ovarian growth, but maximal DEHP exposure stimulated testicular growth. The results indicated that those comparisons can be a useful bio-indicator for determining adverse reproductive effect of endocrine disrupting chemicals (EDCs).

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.70-74
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• 1985

Serum levels of LH, FSH, prolactin, estradiol-$17{\beta}$ and progesterone were investigated every 20 days after the day of mating for the period of 140 days, at the day of parturition and thereafter 10 th and 20th day postpartum in Korean native goats. Serum levels of LH were highest with 1.95 mIU/ml at the 60 days after gestation, but maintained high levels until 100 days after gestation, and thereafter decreased gradually to 0.02 mIU/ml at the day of parturition. Prolactin concentrations increased from the 140 days after gestation, and showed highest levels with 29.75 ng/ml at the day of parturition, then decreased gradually. FSH levels determined were below 1.25 mIU/ml during the experimental period. Estradiol-$17{\beta}$ concentrations increased gradually from 7.51 pg/ml at the 20 days after gestation to 159.62 pg/ml at the day of parturition, and decreased rapidly after parturition. Progesterone levels were highest with 6.62 ng/ml at the 120 days after gestation, the decreased rapidly to 1.25 ng/ml at the day of parturition.