• Clinical and Experimental Reproductive Medicine
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• v.21 no.3
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• pp.305-314
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• 1994

19-norandrostenedione(19-NORA) is known as an intermediate in the metabolic pathway from androstenedione to estrone. Administration of esterified 19-nortestosterone, anabolic steroid, reduces serum gonadotropin and testosterone concentration, and results in reversible azoospermia in men. 19-NORA have been isolated from testis, but its function in testis is not clear yet. Therefore, this study was designed to determine the effect of 19-NORA on steroidogenesis and on spermatogenesis. 19-NORA was administrated by single intratesticular injection to adult male rats weighing 350-400 g in dose of 1 mg/50${\mu}l$. The serum and testis were collected on 1, 3, 7, 12, 48 hr after injection. The histological differences in testis were observed by routine paraffin method. The concentrations of testosterone and estradiol in serum and in left testis were determined by the conventional radioimmunoassays. One hour after 19-NORA treatment, serum concentrations of testosterone and estradiol increased significantly, compared to those of pre-treated(0 hr) group, and reduced gradually to the control level on 7 hour after injection. The concentration of testosterone in left testis increased slightly 1 hour after injection, and estradiol level increased significantly(p<0.05). Also, testosterone and estradiol level of control group revealed no difference with pre-treated (0 hr) group. Gonad index, structure of seminiferous tubules, and the number of step 7 th spermatid were simillar to control group. The present study suggests that the elevation of testosterone level results from increment of estradiol followed by the rapid metabolism of 19-NORA at 7 hour after injection, and then testosterone concentration may be recovered to control level by feedback mechanism of hypothalamus-hypothysis-testis axis.

• Journal of Community Nutrition
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• v.7 no.1
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• pp.29-35
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• 2005

It has been suggested that dietary fat increases the risk of breast cancer by elevating serum estrogen concentrations. However, studies on a relationship between fat intake and breast cancer risk have shown contradictory results, possibly because the levels of fat intake in study populations were too high to observe differences. Also, the effect of other dietary factors may present. The present study was performed to investigate the relationship between diet and estrogen metabolism in premenopausal women whose usual fat intake is relatively low compared to their western counterparts. Twenty lacto-ovo vegetarians (LOV) and twenty omnivores participated in the study. Three day food records including a Saturday or a Sunday were used to estimate nutrient intake. Serum lipids, estradiol, sex-hormone binding globulin, and urinary estradiol were measured. Study results showed $24.8\%$ and $20.9\%$ of energy intake were provided from fat in omnivorous and LOV subjects, respectively. Serum and urinary levels of estradiol were two times higher in omnivores. Fat intake was not related to either serum estradiol nor urinary estradiol when the Spearman correlation coefficient analysis was performed. Carbohydrate, total dietary fiber and soluble dietary fiber intakes were negatively related to serum estradiol concentration. Legumes, vegetables and fruit consumption showed significantly negative relationships with both serum and urinary estradiol concentrations. These results indicate lower estrogen availability may be associated with plant food­based diets in premenopausal women whose usual diets contain less than $25\%$ of energy as fat.

• Journal of Embryo Transfer
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• v.21 no.2
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• pp.109-119
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• 2006

This study was conducted to examine relationship between vaginal cytology and reproductive hormones during the estrous cycle and to provide basic data to estimate for ovulation time and optimal mating time in 6 beagle dogs The duration of proestrus, estrus and diestrus were $8.5{\pm}1.4,\;10.0{\pm}1.4\;and\;54.0{\pm}2.8$ days at pregnant respectively, and $7.9{\pm}2.1,\;9.5{\pm}0.7\;and\;62.0{\pm}11.3$ days at non-pregnant respectively. The duration of interestrous intervals were $246.2{\pm}24.5$ days at pregnancy, and $175.3{\pm}34.5$ days at non-pregnancy. The duration of interestrous intervals at pregnancy was longer than that of non-pregnancy. A characteristic features of vaginal cytology during the estrous cycle were the high proportion of superficial cell, anuclear cell and erythrocyte in proestrus and estrus, parabasal cell, small intermediate cell and leukocyte in diestrus, and parabasal cell and small intermediate cell in anestrus, respectively. Cornification index (CI) in proestrus and estrus were significantly higher than that of CI in diestrus and anestrus. Plasma progesterone concentration was below 1.0 ng/ml at the first day of vulval bleeding at pregnancy and non-pregnancy, and then it was above 2.0 ng/ml at Day -2 in all bitches. When plasma progesterone concentration was first increased above 4.0 ng/ml, it was the second day after the first day of male acceptance. Plasma progesterone concentration showed above 40 ng/ml on Day $20{\sim}22$ in all bitches, and then it was gradually decreased until Day 35. Plasma progesterone concentration at pregnancy was higher than that of non-pregnancy from Day 35 to Day 63. Plasma estradiol-$17\;{\beta}$ concentration was above 9.0 pg/ml at the first day of vulval bleeding, and it showed 26.4 pg/ml on Day -2. When it was timed from the first day of male acceptance (Day 0), plasma estradiol-$17{\beta}$ concentration showed a peak on Day 0 and plasma progesterone concentration was first increased above 4.0 ng/ml on Day 2 which was the third day after plasma estradiol-$17{\beta}$ peak. CI was first increased above 80 and 90% on Day -1 and Day 1, respectively. CI was maintained above 80% from Day -1 to Day 8 (10 days) and above 90% from Day 1 to Day 6 (6 days), respectively. CI was maintained above 80% from Day 0 to Day 8 (9 days) and above 90% from Day 1 to Day 6 (6 days), respectively. Plasma progesterone concentration was first increased above 4.0 ng/ml on the second day after the day which CI was first increased above 90%. In conclusion, beagle bitches ovulated on the second day after the day which CI was first increased above 90% and on the day which plasma progesterone concentration was first increased 4.0 ng/ml, and it was estimated that the optimal mating time was the day which the second day after CI was first increased above 90% and plasma concentration was between $2{\sim}25ng/ml$. The measurement of plasma progesterone was used to determine of and accurate ovulation time and the optimal mating time, but vaginal cytology is low-priced and simple method to estimate estrous cycle, optimal mating time and ovulation time.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.897-900
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• 2000

The experiment was conducted to study the effect of GnRH administration at induced estrus on pituitary and ovarian response in buffalo heifers. Eight Murrah river buffaloes of 12 to 13 months of age were treated with $PGF_{{2}{\alpha}}$ and eCG combination. GnRH (Fertagyl) 200 ug was injected (iv) at estrus in four heifers (treated group) while saline (2 ml, iv) was injected in remaining four heifers (control group). Blood was collected through jugular catheter to estimate plasma FSH, LH and estradiol level. The pretreatment plasma FSH, LH and estradiol values ranged from $8.46{\pm}1.97ng/ml$ to $12.31{\pm}1.30ng/ml$, $0.87{\pm}0.21ng/ml$ to $1.19{\pm}0.29ng/ml$ and $19.09{\pm}2.38pg/ml$ to $20.24{\pm}1.00pg/ml$ respectively. The plasma estradiol concentration elevated significantly (p<0.05) within 24 hr after eCG administration and reached its peak levels of $154.09{\pm}17.28pg/ml$ and $181.95{\pm}31.82pg/ml$ at estrus in respectively treatment and control groups. The plasma FSH and LH concentrations did not increase during follicular development after eCG administration while initial significant (p<0.05) increases in both plasma FSH and LH concentrations occured within 5 and 10 min, reaching peak levels of respectively $110.06{\pm}23.56ng/ml$ and $13.15{\pm}3.13ng/ml$ within 90 min after GnRH injection was detected. A sharp and significant decline in plasma estradiol concentration ($59.27{\pm}8.78pg/ml$) associated with synchronized ovulation within 24 hours after GnRH injection was recorded. The observation suggest that the hypophysis of prepubertal buffaloes treated with eCG have gonadotrophins awaiting the releasing factor to evoke release of gonadotrophin during the follicular phase to induce synchronized ovulation.

• The Korean Journal of Pharmacology
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• v.29 no.1
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• pp.73-83
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• 1993

In order to examine the effect of ${\beta}-estradiol$ on the cell growth, using a primary rabbit kidney poximal tubule cell culture system. We investigated the effect of ${\beta}-estradiol$ on alpha 1 (IV) collagen and ${\beta}-actin$ mRNA levels from primary rabbit kidney cell cultures, and also the effects of 3 growth factors and ${\beta}-estradiol$ supplementation on the growth of primary rabbit kidney proximal tubule cells in the serum-free medium. 1 nM of ${\beta}-estradiol$ showed a sizable potentiation effect on the growth of the proximal tubule cell in serum-free medium, but higher concentration (> 10 nM) of estradiol indeed inhibited the growth. In the absence of hydrocortisone as a growth supplement in serum-free medium, ${\beta}-estradiol$ caused to potentiate the growth of the cell. In the presence of hydrocortisone, ${\beta}-estradiol$ also potentiated the growth of the proximal tubule cells. According to the Northern analysis, ${\beta}-estradiol$ increased the level of ${\beta}-actin$ mRNA, although mRNA level of the alpha I(IV) collagen was not changed significantly.

• Clinical and Experimental Reproductive Medicine
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• v.14 no.1
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• pp.7-17
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• 1987

It appears that a major determinant of the success of in vitro fertilization is the selection of the optimal follicle containing an oocyte capable of being fertilized and producing a normal pregnancy. However, the hormonal basis of oocyte maturation is not well substantiated by the as yet available informations. It has been suggested that prolactin(PRL) may stimulate the formation of an oocyte maturation inhibitor and thus inhibit the maturation of oocyte. During the hyperstimulated menstrual cycles serum estradiol($E_2$) levels are markedly elevated, and it seems justified to assume that serum prolactin levels may be elevated since estrogens are potent stimulators of prolactin secretion. This study was carried out to ascertain the effect of the elevated serum estradiol levels on the serum prolactin levels in women undergoing ovarian hyperstimulation with either hMG and/or clomiphene citrate. Serum estradiol and prolactin profiles were measured from third menatrual cycle day to ovulation or ovum aspiration day in 11 normal menstruating women and 30 women who underwent an in vitro fertilization procedure with ovarian hyperstimulation by hMG, clomiphene citrate/hMG, clomiphene citrate. Ovum aspiration was performed 36 hours after hCG administration. The day of ovum aspiration or ovulation was designated Day 0. Serum estradiol levels increased progressively during the follicular phase and this rise peaked on Day-1 at a mean concentration of 1,204${\pm}$189.0pg/ml in Group II(hMG), 1,194${\pm}$167.9pg/ml in Group III(clomiphene citrate/hMG), 1,035${\pm}$195.1pg/ml in Group IV(clomiphene citrate) respectively and on Day -2 of 336${\pm}$34.5pg/ml in Group I(normal control). The elevated estradiol levels fen rapidly after ovulation or ovum aspiration. Serum estradiol values of hyperstimulated groups(Group II, III, IV) were significantly higher than that of control group(Group I) from Day -6 to Day +1, but there was no significant difference of estradiol values among the hyperstimulated groups. Serum prolactin levels increased and peaked on Day +1 at a mean concentration of 60.8${\pm}$14.4ng/ml in Group II, 34.2${\pm}$7.0ng/ml in Group III, 30.1${\pm}$5.7ng/ml in Group IV respectively, but no significant elevation was observed in Group I. Levels of estradiol and prolactin can be positively and significantly correlated in the hyperstimulated groups. However, the increase of serum prolactin levels in hMG group was significantly higher than those in clomiphene citrate/hMG or clomiphene citrate group.

• Journal of Veterinary Clinics
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• v.31 no.1
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• pp.25-30
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• 2014

This study tested the hypothesis that the priming effects of progesterone on the timing of the LH surge induced by exogenous estradiol are more potentiated the negative feedback actions of progesterone on LH secretion by the existence of estradiol. In previous studies, the time interval from estradiol infusion until the peak of LH surge was gradually and significantly extended by the different levels of progesterone treated before estradiol infusions. Longterm ovariectomized Shiba goats that had received implants of estradiol capsules (Day 0) and three different progesterone silastic packet inducing follicular, subluteal and luteal levels of progesterone were divided into three groups such as non-P, low-P and high-P group. Blood samples were collected daily throughout the experiment for the analysis of gonadal steroid hormone levels. On Day 7, all devices of progesterone and estradiol packets were removed but estradiol capsules were maintained during the experiment, and blood samples were collected at 1 hr interval for 12 h from the time of progesterone removals to determine peripheral changes of estradiol and progesterone concentration. Then all animals were infused estradiol on the Day 7 after 13 h from the removals of progesterone devices with a peristaltic pump into jugular vein at a rate of 3-6 ${\mu}g/h$ for 36 h. For analysis of peripheral LH and estradiol concentration, blood samples were collected via another jugular vein at 2 h intervals for 52 h (from 4 h before the start of estradiol infusion to 48 h after the start of estradiol infusion). In all animals of the three groups treated with estradiol infusion, an LH surge was expressed but the peak time of LH surge was different. This time interval was not extended by the different levels of progesterone treated before estradiol infusions and the difference was not significant during this interval between the Low P and the High P groups. Progesterone pretreatment may contribute to regulating the neural system that is responded by estradiol, and estradiol existence potentiates the negative feedback effect of progesterone on GnRH/LH surge-generating system.

• Korean Journal of Veterinary Research
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• v.37 no.2
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• pp.311-319
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• 1997

The mechanisms of $estradiol-17{\beta}$ regulating growth of both normal and neoplastic cells are not clear until now. In studies using various estrogen-dependent breast cell lines, it is recently known that estrogen controls the cell growth by regulating the expression of growth factors and/or their receptors. In the present study, we investigated the effects of $estradiol-17{\beta}$on cell growth and IGF-I binding sites using primary cultured renal proximal tubule cells. We have obtained results as follows : $Estradiol-17{\beta}(10^{-9})$ has stimulatory effects in cell growth. Cotreatment of $estradiol-17{\beta}(10^{-9}M)$ and $IGF-I(5{\times}10^{-8}M)$ significantly increased the growth of primary rabbit renal proximal tubule cells compared to that of $estradiol-17{\beta}$ or IGF-I alone treated cells. In binding studies, we found that the binding of $^{125}IGF-I$ on cell membranes was incubation time- and temperature-dependent. Incubation at $37^{\circ}C$ results in higher binding of $^{125}IGF-I$ than that of $23^{\circ}C$ or $4^{\circ}C$. Maximum binding was observed at $37^{\circ}C$ between 30 and 60 minutes. The binding of $^{125}IGF-I$ to both control and $estradiol-17{\beta}-treated$ cells was inhibited by unlabelled $IGF-I(10^{-8}{\sim}10^{-12}M)$ in a concentration-dependent manner. However, EGF did not compete for $^{125}IGF-I$ binding at $10^{-8}{\sim}10^{-12}M$. IGF-I binding to the membranes from both control and $estradiol-17{\beta}-treated$ cells was also analyzed. We found that $estradiol-17{\beta}-treated$ cells exhibited higher binding activity for IGF-I. When $estradiol-17{\beta}$ or tamoxifen alone, or $estradiol-17{\beta}$ and tamoxifen cotreated cells were compared, the binding ratio of $^{125}I-IGF-I$ of $estradiol-17{\beta}-treated$ cell was significantly increased but was similar to control in both $estradiol-17{\beta}$ and tamoxifen cotreated cell. These results suggest that $estradiol-17{\beta}$ in part controls cell proliferation by regulating the expression of IGF-I receptors in primary rabbit renal proximal tubule cells.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.3
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• pp.69-82
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• 2006

Purpose : Taraxaci Herba is a herb with an effect on extravasated blood and is widely used in gynecology. This study examined the effects of Taraxaci Herba on endometriosis. Methods : Rats with surgically induced endometriosis were given an oral dose of Taraxaci Herba for 40 days. The size of the ectopic uterine implants at the serosal wall and the concentration of progesterone, estradiol, tumor necrosis factor-${\alpha}$(TNF-${\alpha}$) and interleukin(IL)-2, 4, 6, and 10 in the blood were examined and compared with the control group. Results : The size of the ectopic uterine implants in the treated group was much smaller than that in the control group. The estradiol concentration was significantly lower in the experimental group than in the control group. The IL-10 level was higher and the TNF-${\alpha}$, IL-2 and IL-4 concentration were lower in the experimental group than in the control group and there was statistically significant difference. There was no significant difference in the IL-6 level between the experomental and the control group. Conclusion : These results indicate that Taraxaci Herba reduces the size of ectopic uterine implants at the serosal wall and inhibits the growth of ectopic uterine implants. This suggests that Taraxaci Herba is an effective treatment for endometriosis.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.756-762
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• 2003

In the current study, our research focused on the estrogenic activity of isoflavonoids, mainly genistein, biochanin A and daidzein. Genistein enhanced the reporter gene expression of MCF-7-ERE-Luc cells, at a concentration as low as 10 nM, with a concentration of 100 nM the achieved gene expression effects were similar to those of 10 pM 17$\beta$-estradiol. Based on the estrogenic activities of biochanin A and daidzein, hydroxyl groups at the 4 and 5 positions are needed for the maximal effect of the genistein. The estrogenic effects of these isoflavonoids were inhibited by the concomitant treatment with tamoxifen. The data showed that the estrogenic effects of isoflavonoids were mediated through estrogen receptors. When the isoflavonoids were tested as mixtures, the estrogenic effects were lower than the arithmetic sum of those induced by each individual isoflavonoid. The estrogenic potency of each isoflavonoid was presented at EC50 levels with a 17$\beta$-estradiol equivalent concentration (EEQ) based on the dose response of each chemical. The EC50s and EEQs of genistein, biochanin A and daidzein were 4.15, 0.89 and 0.18 $\mu$M, and 15.0, 5.12 and 1.83 $\mu$ M/M, respectively. Our data clearly demonstrated that the pERE-luciferase reporter gene assay was suited for the sensitive and quantitative measurement, and large scale screening, of the estrogenicity of chemicals in vitro.