• Development and Reproduction
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• v.9 no.1
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• pp.15-22
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• 2005

The objective of the present study was to investigate changes of sex steroid(testosterone: T and $estradiol-17{\beta}:\;E_2$), cortisol levels and gonadal development following $T_3$ treatment to protandrous black porgy, Acanthopagrus schlegeli. Exogenous $T_3$ was found to significantly stimulate the increase of T levels in plasma of black porgy after 60 days of treatment. However no effects of $T_3$ on $E_2$ levels and oocyte size were found. $T_3$ treatment resulted in stimulated spermatogenesis and testicular development in gonad and prolonged spermiation. Also, the levels of cortisol were significantly increased in the fish treated with $T_3$ as compared to control fish at 60 days. The results showed that exogenous $T_3$ had direct effect on the release of T and cortisol, thus $T_3$ seems to play, either directly or indirectly, an important role in the testis development of functional male black porgy.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.346-351
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• 2002

The effect of fetal number (single or twin) on plasma concentrations of progesterone, estradiol $17{\beta}$, cortisol, prolactin, growth hormone, triiodothyronine, thyroxine and insulin around parturition (periparturient period) were studied on ten $Alpine{\times}Beetle$ crossbred goats in their first to third lactation. The hormone profiles were studied on days -20, -15, -10, -5, -4, -3, -2, -1 prior to kidding and on day 0 and +1, +2, +3, +4, +5, +10, +15, +20 days postkidding. Plasma progesterone levels were significantly (p<0.01) higher in twin bearing goats comparison to single bearing goats during all the days of sampling. The decline in progesterone concentration from day 20 to day 1 before kidding was 56% in twin and 42% in single bearing goats. In single bearing goats plasma estradiol $17{\beta}$ was significantly (p<0.01) higher during prekidding days compared to twin bearing goats. The level of estradiol $17{\beta}$ was highest on the day of kidding in both the groups. The plasma prolactin level in twin bearing goats from day 10 to day 1 prepartum was higher as compared to single fetus bearing goats. However there was abrupt increase in prolactin level on the day of kidding in both the groups. The plasma growth hormone levels were significantly (p<0.01) higher in twin compared to single bearing goats. On the day of kidding growth hormone levels were significantly (p<0.01) higher in twin as compared to single bearing goats (1.40 vs. 0.95 ng/ml). In twin bearing goats plasma cortisol values from day 5 till the day of kidding remained elevated and the levels on the day of kidding was significantly highest in both the groups. The levels of triiodothyronine ($T_3$) were significantly higher (p<0.01) during all the periods of sampling in single compared to twin bearing goats. Plasma thyroxine ($T_4$) was significantly (p<0.01) lower in twin compared to single bearing goats. In single bearing goats plasma insulin levels were significantly (p<0.01) higher than twin bearing goats during prepartum period however during post partum period the levels in both the groups remained similar. It can be concluded that number of fetuses is having significant influence on the hormone profile during periparturient period.

• Journal of Aquaculture
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• v.11 no.3
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• pp.311-317
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• 1998

Effects of Cu and Zn on estradiol-17$\beta$-Induced vitellogenin (VTG) production were electro-phoretically examined in hepatocyte cultures of rainbow trout. Hepatocytes were precultured for 2 days and then Cu ($10^{-5}$ ~$10^{-4}$M) and Zn ($10^{-5}$~$10^{-3}$M) were added to the incubation medium with estradiol-17${\beta}$ ($2{\times}10^{-6}$M). The hepatocytes were cultured for 5 more days. The relative VTG production rate was expressed as the percentage of VTG to total proteins including the VTG. The addition of CU and Zn to the incubation medium had no appreciable toxin effect on the viability of hepatocytes in the culture. However, Cu markedly reduced VTG production at any concentration used. Zn also specifically reduced VTG production by hepatocytes in a concentration dependent way and there was a significnt reduction at Zn concentrations of $10^{-3}$M. The reduction recovered by removing Zn from the media, but Cu did not. Additionally, enriched Ca concentrations (1.8 to 2.5 or 5.0 mM) in the incubation medium had no protective effect on the reduction of VTG production by Cu $10^{-4}$ M. These results suggest that the production of VTG is more susceptible to Cu and Zn than are other hepatocyte-derived proteins.

• Development and Reproduction
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• v.22 no.2
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• pp.155-163
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• 2018

This study aimed to investigate changes in the activity and mRNA expression of plasminogen activators (PAs) induced by $17{\beta}$-estradiol ($E_2$), human chorionic gonadotropin (hCG), and interleukin-$1{\beta}$ ($IL-1{\beta}$) in porcine endometrial cells. Endometrial cells were isolated from the epithelium and cultured to 80% confluence. They were then treated for 24 h with $E_2$ (0.2, 2, 20, and 200 ng/mL), $IL-1{\beta}$ (0.1, 1, 10, and 100 ng/mL), and hCG (0.5, 1, 1.5 and 2 IU/mL). mRNA expressions of urokinase-type (uPA) and tissue-type (tPA) PAs were analyzed using reverse transcription PCR, and activities were measured using a PA activity assay. mRNA expressions of uPA and tPA increased with $E_2$ treatment; however, this was not significant. Similarly, treatment with hCG did not influence the mRNA expressions of PAs. Interestingly, treatment with 0.1 ng/mL $IL-1{\beta}$ significantly reduced the mRNA expression of uPA, but did not affect that of tPA. Treatment with 2, 20, and 200 ng/mL $E_2$ increased PA activity compared with the control group; treatment with 0.1 and 1 ng/mL $IL-1{\beta}$ significantly increased PA activity compared with the other $IL-1{\beta}$ treatment groups, whereas treatment with 10 and 100 ng/mL $IL-1{\beta}$ decreased. Treatment with 2 IU/mL hCG increased PA activity compared with the other treatment groups, although there were no significant differences between the hCG and control groups. In conclusion, the activity and mRNA expression of PAs were differently regulated by the hormone/cytokine and its concentration in porcine endometrial cells. Therefore, understanding PA regulatory mechanisms may help to improve the reproductive potential of domestic animals.

• Korean Journal of Animal Reproduction
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• v.14 no.3
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• pp.175-182
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• 1990

Behavioural estrus and short estrous cycles were observed and serum concentrations of estradiol-17$\beta$(E2) before and after of estrous were measured following superovulation treatments in 30 pluriparous Korean native goats. The goats were divided into 2 groups. Fifteen goats were injected IM with 1,000IU PMSG on Day 12 of the estrous cycle followed by 10mg PGF2$\alpha$ 48h later(P4＋PMSG), and the other 15 goats were injected IM with 10mg progesterone(P4)in oil once daily for 10d beginning at any days of estrous cycle followed by 1,000IU PMSG and 10mg PGF2$\alpha$ at the 8th day of progesterone treatment(P4＋PMSG group). After injection of PGF2$\alpha$, onset of standing estrus occurred in 12 of 15 goats(80.0%) at 50.0$\pm$7.7h and in 11 of 15 goats(73.3%) at 135.6$\pm$10.1h in PMSG and group and P4＋PMSG group, respectively. The mean interval from PGF2$\alpha$ injection to first estrus was significantly(P<0.01) earlier in PMSG group than in P4＋PMSG group. This result indicate that the delayed infusion of P4 in P4＋PMSG group caused the later exhibition of their estrous behaviors. However, duration fo frist estrus(31.5$\pm$2.6h vs 26.2$\pm$2.3h), length of estrous cycle(14.1$\pm$3.3d vs 16.6$\pm$3.8d) and percentage of short estrous cycle(50.0% vs 45.5%) were not different between PMSG and P4＋PMSG group. The mean concentration of serum E2 in 4 goats showing normal estrous cycle in P4＋PMSG group(PP-NEC) was higher than in 6 goats showing normal(P-NEC) or in 6 goats showing short estrous cycle(P-SEC) in PMSG group. The peak level of serum E2 was observed at the time of onset of standing estrus in PP-NEC(67.6pg/ml), 6h earlier in P-NEC(53.1pg/ml) and 6h later in P-SEC(52.3pg/ml) than the onset of standing estrus. The profiles of serum concentration of E2 during the period of peri-estrus was similar in the goats of PMSG or P4＋PMSG and also in the goats showing the subsequent estrous cycle of normal or short length.

• Korean Journal of Animal Reproduction
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• v.7 no.1
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• pp.41-51
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• 1983

The purpose of this experiment was to investigate the effects of adrenalectomy and PMSG treatment on reproductive organs and serum steroid hormone level in immature female rats. The animals used in this experiment were 25 days old female rats weighing a, pp.oximately 70g. They were randomly divided into two groups of intact rat group (Int-) and adrenalectomized rat group (Adx-) and each group were subdivided into two groups of Non-PMSG (-Cont) and PMSG treated (-PMSG) group. The rat of PMSG-treated group (-PMSG) was administered subcutaneously with 25 IU PMSG on first day (9 a.m.) after adrenalectomy. The adrenalectomized rat groups were su, pp.ied with saline solution through the experiment period. The rate of ovulation and vaginal opening and reproductive organ weights were observed at 8, 32, 56, 80 and 104 hours after PMSG treatment. At the same time, the serum level of estradiol-17${\beta}$ and progesterone were measured by the radioimmunoassay. The results obtained were as follows: 1. Ovulation was shown at 56 hours after treatment in Int-PMSG group and Adx-PMSG group and Adx-PMSG group. The rate of ovulation was very low in PMSG-treated groups, but it was increased in 80 to 90% at 104 hours after treatment. However, there was no ovulation in Int-Cont group and Adx-Cont group. 2. Vaginal opening was shown at 56 hours after treatment in Int-PMSG group and Adx-PMSG group and a, pp.ared in 80% at 104 hours after treatment. The rate of vaginal opening in PMSG-treated groups was very low, but Int-Cont group and Adx-Cont group had no vaginal opening. 3. The weight of ovary and uterus in two PMSG-treated groups were increased with the elapse of time after treatment and were significantly heavy in all observation time, but changes in Int-Cont group and Adx-Cont group were not recognized. The weights of ovaries and utera in Adx-Cont group were increased with the elapse of time. 4. The level of serum estradiol-17${\beta}$ was remarkably increased in PMSG-treated groups (Int-PMSG and Adx-PMSG groups) compared with Int-Cont and Adx-Cont group, and significant difference was recognized between Non-PMSG group and PMSG-treated group in the experimental period. Especially, the highest levels of Int-PMSG groups and Adx-PMSG groups were shown at 80 and 56 hours after treatment and after ward estradiol-17${\beta}$ levels of PMSG-treated groups were decreased. However, changes of the levels did not a, pp.ared in Non-PMSG groups at 104 hours after treatment. 5. The level of serum progesterone in PMSG-treated groups was significantly increased between 80 and 104 hours after treatment. With the elapse of time, the level was increased in all observed groups except for Int-Cont and Adx-Conx group. And the order from the highest level at 104 hours after treatment was Int-PMSG, Adx-PMSG, Int-Cont and Adx-Cont group.

• Korean Journal of Veterinary Research
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• v.39 no.2
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• pp.276-286
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• 1999

In the present study, to understand how gonadotropin-releasing hormone (GnRH) affects ovarian functions in superovulated rats, we examined the effects of GnRH agonist on the ovulatory response, the morphological normality and nuclear maturation of ovulated oocytes, the ovarian weight, the ovarian histology, and the circulating steroid hormone ($17{\beta}$-estradiol, progesterone and testosterone) levels in immature rats pretreated with 30IU pregnant mare serum gonadotropin (PMSG) and supplemented with 10IU human chorionic gonadotropin(hCG). GnRH agonist was intravenously injected via jugular vein catheter every 20min for 4hrs in early follicular phase (from 6hr after PMSG) of superovulated rats. In addition, GnRH antagonist, Antide, was intravenously injected in combination with GnRH agonist to verify the effects of GnRH agonist on ovarian functions. All animals were sacrificed at 72hr after PMSG administration. The administration with GnRH agonist in early follicular phase of superovulated rats caused inhibition of ovulatory response, increased the proportion of abnormal appearing oocytes(especially, in the rats of the group treated with 500ng GnRH agonist), decreased ovarian weight and promote follicular atresia, compared to those from the rats of control regimen that were not treated with GnRH agonist. In addition, the treatment with GnRH agonist in the superovulated rat distinctly decreased serum steroid hormone ($17{\beta}$-estradiol, progesterone and testosterone) levels in preovulatory phase. On the other hand, the inhibitory effects of GnRH agonist treatment in superovulation-pretreated rats on ovarian functions were totally reversed by the combination with GnRH antagonist, Antide. The nuclear maturation of oocytes recovered from the oviducts in immature rats treated with GnRH agonist and/or GnRH antagonist was characterized by prematurity and asynchronization in early follicular phase, which was similar to control group. The overall results of this study indicate that GnRH agonist disturbs directly ovarian function in early follicular phase of superovulated immature rats in terms of ovulatory response and morphological normality of ovulated oocytes. This concept has been further evidenced by the findings of a great decrease in ovarian weight, a marked increase in follicular and a distinct decrease circulating steroid hormone ($17{\beta}$-estradiol, progesterone and testosterone) levels in GnRH agonist treatment regimen in early follicular phase.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.55-61
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• 1985

This study was carried out to investigate reproductive traits and sex hormone levels by growth in Korean native goats. Serum levels of FSH, LH, prolactin, estradiol-$17{\beta}$ and progesterone were determined every 15 days from the 70 days of age to 190 days by radioimmunoassay. The age and weight at sexual maturity were 183.6 days and 14.3 kg; the length of estrous cycle and estrus period were 20.3 days and 36.7 hours, respectively. The gestation period, litter size and body weight at birth were 148.4 days, 1.4 head and 1.8 kg, respectively. The levels of serum LH were highest with 3.93 mIU/ml at 70 days of age, thereafter decreased gradually to 1.21 mIU/ml at 190 days of age. The concentrations of FSH in serum were below 1.25 mIU/ml throughout the experimental period. The levels of prolactin were lowest with 3.09ng/ml at 85 days of age and highest with 4.65 ng/ml at 175 days of age. The serum levels of estradiol-$17{\beta}$ were increased with age, thus highest with 7.95 pg/ml at 190 days of age. The serum progesterone concentrations were maintained low levels (below 1.0 ng/ml) throughout the experimental period.

• Clinical and Experimental Reproductive Medicine
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• v.14 no.1
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• pp.61-70
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• 1987

This study was carried out to investigate the effects of the antiestrogens, LY-117018 and tamoxifen on reproductive organ of ovariectomized immature rats and also to elucidate the mechanism of action of said compounds by bioassay. Each of LY-117018, tamoxifen and estradiol-17${\beta}$ was administered to ovariectomized immature rats at various dose levels. Forty hours after drug administration, tested rats were sacrificed and uterine wet weight, DNA and RNA contents in uterine and liver tissues were investigated. At the same time, uterine wet weight was also investigated with some other rats treated with 125${\mu}g$ of LY-117018 together with increasing doses of tamoxifen. Ovariectomized immature rats given 25${\mu}g$ single dose of each drug were sacrificed on Day 1, 2, 3, 4, and 5 after drug administration and uterine was weighed to estimate the duration of action of LY-117018 and tamoxifen. The results were summarized as follows: 1. The administration of LY-117018 or tamoxifen to ovariectomized rats increased uterine wet weight and DNA and RNA contents in uterine tissues with more increase in tamoxifen groups, but significant differences between groups treated at dose levels of 5${\beta}$ or more of both drugs were observed. Estradiol-17${\beta}$ groups showed significant increases in each group(P<0.01). 2. The administration of LY-117018 or tamoxifen to each group significantly increased DNA and RNA contents in liver tissues with more increase in tamoxifen groups. Estradiol-17${\beta}$ groups showed no significant differences between treatment groups of 5${\beta}$ or more. 3. Treatment with 125${\beta}$ of LY-117018 together with various doses of tamoxifen resulted in more increase of uterine wet weight than treatment with a single dose of LY-117018 or tamoxifen. 4. Treatment with 0.2${\beta}$ of LY-117018 or tamoxifen in ovariectomized rats decreased uterine wet weight,DNA and RNA contents in liver and uterine tissues compared with ovariectomized control. 5. The duration of effective action of LY-1l7018 and tamoxifen was 4 days or more. 6. There was significant difference(P<0.001) in uterine wet weight between Day 9after ovariectomy (two days after LY-117018 or tamoxifen treatment) and Day 10(63.7${\pm}$3.5mg, 39.2${\pm}$9.9mg, respectively).

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.743-749
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• 2005

Estrogen is known to play an important role in maintaining bone mass, since the concentration of serum estrogen decrease after menopause and the estrogen deficiency results in bone loss. Phytoestrogens are plant compounds with estrogen-like biological activity, In this study, to investigate the bioactivities of phytoestrogen, which act on bone metabolism, we examined the effect of selected food-borne phytoestrogens (genistein, daidzein and resveratrol) on osteoblast proliferation and IGF-I production using MC3T3-El cells, a mouse calvaria osteoblast-like cell line. Cells were cultured in a serum free medium for 48 hr in the presence of genistein $(10^{-5}\;M)$, daidzein $(10^{-5}\;M)$ and resveratrol $(10^{-5}\;M)$. The effects of genistein, daidzein and resveratrol on the cell proliferation and growth were evaluated by total cell numbers, MTS assay and cell migration assay. Their effect was compared with the $17\beta-estradiol$. Genistein, daidzein and resveratrol exhibited stimulatory effects on the growth of MC3T3-El cells, and the most pronounced effect was shown with daidzein. In addition, these phytoestrogen increased alkaline phosphatase activity of MC3T3-El cells. These effects were similar to that of $17\beta-estradiol$ effects. Moreover, treatment with genistein, daidzein and resveratrol increased production of insulin like growth factor-I (IGF-I) in conditioned media, indicating that the growth promoting effects of these phytoestrogen were related to the changes in production of IGF-I by MC3T3-El cells. These results show that genistein, daidzein and resveratrol have a stimulatory effect on osteoblast function, and that these findings in a cell model may prove relevant to protecting against the loss of bone mass and the development of osteoporosis in human subjects.