• 한국수정란이식학회지
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• 제33권4호
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• pp.297-304
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• 2018

The purpose of the present study was to determine the elaborate characteristics of ovarian changes including follicles and corpus luteum, and hormonal patterns of gonadotropin surge mode secretions during the normal consecutive estrous cycle in three dairy cows. Non-lactating and multiparous Holstein cows (n=3) used as experimental animals. The cows were assigned to examine the relationship among ovarian changes (follicle, corpus luteum), ovarian steroids (estradiol, progesterone) and gonadotropin (LH, FSH) surge mode secretion during the successive estrous cycles by rectal palpation, ultrasonography and hormonal assay. The mean length of the estrous cycle for the three cows was $23.1{\pm}1.44days$ (${\pm}SEM$), with a range of 20-28 days. In six estrous cycles, the number of two follicular waves, three follicular waves and four follicular waves was 2, 3 and 1, respectively. The sequential ultrasonographic monitoring showed that the corpus luteum with ${\geq}10mm$ in diameter detected from Day 2 (Day 0 is ovulation) in six estrous cycles of all cows. Preovulatory increases in estradiol concentration reached $10.36{\pm}1.10pg/ml$ on the 2 days before ovulation of the last dominant follicle. All cows exhibited a preovulatory rise in estradiol concentration followed by a typical preovulatory LH and FSH surge. The mean interval from the peak of LH/FSH surge to ovulation of the last dominant follicle was $31.3{\pm}1.76h$ (${\pm}SEM$). In these results, each dairy cow showed that ovarian morphological changes and gonadotropin surge mode secretion will be regulated by various environmental factors including age, breeds, nutrition, breeding conditions, etc.

• Clinical and Experimental Reproductive Medicine
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• 제22권2호
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• pp.155-161
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• 1995

The present investigation has been undertaken to elucidate the differentiation mechanism the uterus which is the environment of the embryo development, by demonstrating the role of ovarian steroids hormone in the decidualization of the pseudopregnant rat uterus. To determine the effect of ovarine steroids and artificial stimulation (trauma) on the differenciation of the uterine endometrium and decidualization for implantation, attempt was made to measure concentrations of serum estradiol($E_2$), progesterone($P_4$) and nuclear $P_4$ receptor in the traumatized and non-traumatized uterine tissue of the pseudopregnant rat. The results obtained are as followings : The concentration of serum $E_2$ on day 9(implantation stage) was similar in both of intact pseudopregnant rat(47.63pg/ml) and normal pregnant rat(40.71pg/ml). And among the treated groups, $E_2$ concentration was highest in the $E_2$ treated group in comparision with intact control group(relative value; 73.27%). The concentration of serum $P_4$ was also highest in the $P_4$ treated group(23.12pg/ml). Relative value of $P_4$ treated group in comparision with intact group(24.88pg/ml) was 92.93%. The nuclear $P_4$ receptor levels in the artificial traumatized groups were higher compared with the non-traumatized control groups. This study, therefore, clearly demonstrates that the methods for inducing pseudopregnant (vagina tapping;120/min) and inducing decidualization(oil injection; 0.1ml/uterine horn) appear to be effective, $P_4$ appears to be effective in the differenciation of the uterine endometrial tissue for the implantation process. Concentration of serum $P_4$ seems to be well correlated with the level of the nuclear $P_4$ receptor during the early embryo development. These results seem to be well correlated with ALPase activities in the normal and pseudopregnant rat uterus shown in the previous study.

• Fisheries and Aquatic Sciences
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• 제25권1호
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• pp.12-19
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• 2022

In the present study, we investigated the effects of recombinant eel gonadotropins (rec-GTHs) on maturation induction in immature ovarian culture in vitro and sex steroid hormones in vivo in the Japanese eel Anguilla japonica. To study the in vitro effects of rec-GTHs on estradiol-17β (E2) production in immature ovarian tissues, ovarian tissues were incubated with different doses of rec-follicle-stimulating hormone (rec-FSH) or rec-luteinizing hormone (rec-LH). The results revealed that the E2 levels in the rec-FSH (0.1, 0.5, or 1 ㎍/mL)- and rec-LH (0.1 or 0.5 ㎍/mL)-treated groups were significantly higher than those in the female eels from the control group. Furthermore, to investigate the in vivo effects of rec-GTHs on the gonadosomatic index (GSI) and plasma sex steroid hormone levels, the eels were injected intraperitoneally with eel's ringer (control), salmon pituitary extract (SPE; for female eels), human chorionic gonadotropin (hCG; for male eels), rec-FSH, rec-LH, and rec-FSH + rec-LH once a week. The results revealed that except for the SPE and the hCG groups, none of the groups exhibited a significant difference in GSI values. However, in vivo plasma E2 levels increased at the end of 4 weeks after rec-FSH treatment in female eels. Based on these results, it is suggested that rec-GTHs may have a positive effect on sexual maturation in female eels; however, further studies on complementary rec-protein production systems and additional glycosylation of rec-hormones are needed to elucidate hormone bioactivity in vivo and in vitro.

• Clinical and Experimental Reproductive Medicine
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• 제18권1호
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• pp.41-48
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• 1991

The present investigation has been undertaken to elucidate the functional role of ovarian steroids on the mechanism of oviduct differentiation during early embryonic development in rat. The activity of alkaline phosphatase (ALPase) was measured in the oviduct tissue under different steroids treatment regime on day 9 pregnancy. The ALPase activity of the oviduct of pseudopregnant rat was compared with that of normal pregnant rat. The results of day 9 pregnancy rat oviduct clearly demonstrated that $17{\beta}-estradiol$ and progesterone were effective in pseudopregnant rat oviduct. In the ovary intact group the ALPase activity was similar in both of normal and pseudopregnant oviduct, but in the $17{\beta}-estradiol$ treated group the ALPase activity in normal pregnancy was significantly higher than that in pseudopregnancy. The effect of estradiol on the normal pregnant rat oviduct was apparently found on day 3 and day 9 pregnancy. This study, therefore, clearly demonstrates that $17{\beta}-estradiol$ is much potent in oviduct tissue differentiation. It is suggested that absence of $17{\beta}-estradiol$ effect on pseudopregnant rat oviduct is due to there is no embryo passing througth the oviduct.

• Animal cells and systems
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• 제1권1호
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• pp.115-121
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• 1997

To precisely analyze the role of ovarian steroids in the regulation of laminin chain gene expression in mouse uterine tissues, the ovariectomized mouse model was used. Ovariectomized mice received a single injection of steroid hormones and total RNA was isolated from whole uterine tissues. Messenger RNA levels of each laminin chain (A, 81, and 82) were determined by competitive RT-peR procedures. Estradiol decreased mRNA levels of laminin 81 chain about two-fold, and 82 chain rather moderately. Estradiol-induced inhibition of laminin 81 and 82 chain mRNA levels were completely blocked by pretreatment with estrogen receptor antagonist tamoxifen. Estriol, a short acting estrogen which cannot induce hyperplastic responses of rodent uterine tissues, also showed an inhibitory effect on 81 and 82 chain mRNA levels, while estrone, an inactive estrogen, failed to influence either 8 chain mRNA levels. Effects of steroids on A chain mRNA level were quite different from those on 8 chains. Laminin A chain mRNA level was slightly increased by estradiol treatment, but negatively affected by progesterone. Progesterone treatment greatly increased both 8 chain mRNA levels, but slightly decreased A chain mRNA level compared to the control. The effect of progesterone on laminin chain-specific mRNA levels was further increased by co-injection of estradiol in a time-dependent manner. Progesterone-induced 81 and 82 chain mRNA transcription was inhibited by RU486, a synthetic anti-progesterone /anti-glucocorticoid. The present study demonstrates for the first time that steroids are able to regulate laminin gene expression in mouse uterine tissues, indicating that steroid-regulated laminin gene expression is involved in uterine growth and probably differentiation.

• Clinical and Experimental Reproductive Medicine
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• 제28권4호
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• pp.255-264
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• 2001

Objective : This study was performed to investigate the effect of metformin therapy on ovulation induction & pregnancy rate in clomiphene citrate-resistant PCOS women. Method: This study used a randomized, single-blinded, case-controlled methods. Total study group consisted of 21 women who showed clomiphene citrate-resistant parttern on previous ovulation induction cycles. Patients of metformin group received metformin 500 mg three times daily, for 7 weeks. Control group received none. Metformin group was consisted of 10 women and control group was consisted of 11 women. Then clomiphene was administrated at daily 50 mg for 5 days to both groups. Clomiphene dosage was increased to daily 150 mg until ovulation was occurred. Before and After metformin treatment, blood samples for measurement of insulin, glucose, steroids were obtained. Results: In the metformin and control groups, 6 of 10 women (60%) and 2 of 11 women (18%) ovulated. And 4 of 10 women (40%) and 0 of 11 women (0%) conceived. Comparisons between the groups were significant. Conclusion: In PCOS women who are resistant to CC, metformin use increased the ovulation rate and pregnancy rate from CC treatment, significantly.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.240-240
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• 2004

The modification of in vitro maturation (IVM) conditions should be required to efficient production of matured porcine oocyte in vitro. Estradiol-17β (E₂) as steroid hormone exists in ovarian follicular fluid and plays a major role in ovulation. It has been reported that estradiol as well as other steroids are involved in keeping the oocytes in meiotic arrest. (omitted)

• Clinical and Experimental Reproductive Medicine
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• 제11권2호
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• pp.41-49
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• 1984

임신직후 자궁조직은 난소 스테로이드 호르몬에 의하여 분화한다. 착상전 여러 단계에 있는 자궁조직내의 cAMP의 함량을 측정함으로서 cAMP와 호르몬과의 관계를 규명할 목적으로 흰쥐를 재료로 해서 본 실험을 행하였다. 임신제 2일에 난소를 제거하고 즉시, 제3, 또는 제 4일에 estradiol과 progesterone 을 각각 혹은 동시에 주사한 뒤 대조군인 정상임신군, 난소제거군, 난소제거후 호르몬주사군의 자궁조직에서 cAMP농도를 competitive protein-binding assay로 측정하여 이를 각각 비교하였다. 본 연구결과는 다음과 같았다. 정상임신군인 경우 자궁조직이 분화해 갈수록 자궁조직내 cAMP의 농도는 낮아지고 있다. 난소제거군에서는 임신기간이 길수록 자궁조직내의 cAMP농도가 높아진다. 난소제거후 progesterone 혹은 progesterone 과 estradiol을 주사한 실험군에서는 임신 제 6일이 되면 cAMP 농도가 정상임신군과 난소제거군의 중간수치를 보여준다. 한편, estradiol 단독주사인 경우는 임신제3, 제6일의 자궁조직내의 cAMP의 농도는 크게 감소한다. 이처럼 estradiol의 영향아래 세포분열등 분화가 왕성한 자궁조직에서는 cAMP 농도가 크게 낮아지지만 자궁조직의 분화가 억제된 상태에서는 cAMP의 농도가 반대로 높아진다. 난자, 배아 또는 여러 형태의 세포에서처럼 cAMP의 농도는 세포의 대사에 크게 영향을 주고 있다는 것을 알 수 있었다.

• 한국수산과학회지
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• 제37권3호
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• pp.192-196
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• 2004

The in vitro effect of bisphenol A (BPA) on ovarian steroidogenesis of the longchin goby (Chasmichthys dolichognathus) was investigated. Oocytes taken during the maturing phase (vitellogenic, fully vitellogenic or germinal vesicle breakdown stage) were incubated with BPA (100 ng/mL) in the presence of exogenous precursor $^{3}H-17\alpha\;hydroxyprogesterone\;(^{3}H-17\alphaOHP).$ Steroids were extracted from the media and the isolated oocytes, and the extracts were separated and identified by thin layer chromatography and gas chromatography-mass spectrometry. The identities of the major metabolites were progestogens $[17{\alpha}-hydroxy,20{\alpha}-dihydroprogesterone\;(17{\alpha}20{\alpha}OHP)\;and\;17{\alpha}-hydrxy,20{\beta}-dihydroprogesterone\;(17{\alpha}20{\beta}OHP),$ androgens [androstenedione (A4) and testosterone (T)] and estrogens [estrone $(E_1)\;and\;estradiol-17{\beta}(E_2)].$ BPA treatment inhibited production of estrogens in all the maturing phases and progestogens in the germinal vesicle migrating stage. Percentage yield of estrogens was decreased with increased yield of androgens. In conclusion, BPA had an inhibitory effect on the conversion of $^3H-17\alphaOHP$ to estrogens and progestogens. These results demonstrate that BPA can act either estrogenic or anti-estrogenic effects.

• 대한약리학회지
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• 제29권2호
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• pp.225-235
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• 1993

난소호르몬에 의하여 황체형성호르몬(luteinizing hormone; LH) subunit의 유전자 발현이 어떻게 조절되는가를 조사하기 위하여 성숙한 흰쥐에서 난소를 제거하거나 또한 난소호르몬을 재 투여한 후 ${\alpha}$ 및 $LH{\beta}$ subunit mRNA의 수준을 조사하여 다음과 같은 결과를 얻었다. 1. 난소를 제거한 후 시간이 경과함에 따라 혈중 LH 농도 및 뇌하수체 LH 함량이 급격히 증가하였다. 또한 난소제거 후 14일 후부터 ${\alpha}$ subunit mRNA 수준이 증가하기 시작하였으며, $LH{\beta}$ subunit mRNA 수준은 난소제거 후 1일부터 증가하기 시작하여 혈중 LH 농도와 같은 양상으로 증가하였다. 2. 난소제거 후 21일 경과후에 난소호르몬을 투여하였을때 난소제거로 증가된 혈중 LH 농도와 ${\alpha}$ 및 $LH{\beta}$ subunit mRNA 수준이 감소하였다. Estradiol을 1일간 투여하였을때 부터 혈중 LH 농도 및 ${\alpha}$와 $LH{\beta}$ subunit mRNA 수준이 감소하였으며, progesterone을 4일간 처리하였을때에 혈중 LH농도가 감소하였다. 3. Estrogen 길항제인 LY117018를 estradiol과 동시에 처리하거나, progesterone 길항제인 RU 456을 progesterone과 동시에 처리하였을때 estradiol과 porgesterone에 의하여 감소되었던 혈중 LH 농도 및 ${\alpha}$와 $LH{\beta}$ subunit mRNA 수준이 유의하게 회복되었다. 이상의 결과로 보아 LH 분비에 있어서 $LH{\beta}$ subunit mRHA 수준의 변화가 속도결정단계 (rate limiting step)인 것으로 보이며, 난소홀몬은 ${\alpha}$ 및 $LH{\beta}$ subunit mRNA 수준을 조절하므로써 pretranslation 단계에서 LH 생합성을 조절하는 것으로 생각된다.