• 한국발생생물학회지:발생과생식
• /
• 제13권3호
• /
• pp.163-172
• /
• 2009

Some organotin compounds such as butyltins and phenyltins are known to induce impo-sex in various marine animals and are considered to be endocrine disruptors. In this study, the effect of organotins on follicular steroidogenesis in amphibians was examined using ovarian follicles of Rana dybowskii and Rana catesbeiana. Isolated follicles were cultured for 6 or 18 h in the presence and absence of frog pituitary homogenate (FPH) or various steroid precursors, and the levels of product steroids in the culture media oassay. Among the butyltin compounds, tributyltin (TBT) strongly and dose-dependently inhibited the FPH-induced synthesis of pregnenolone ($P_5$) and progesterone ($P_4$) by the follicles. TBT also strongly suppressed the conversion of cholesterol to $P_5$ and partially suppressed the conversion of $P_5$ to $P_4$. A high concentration of dibutyltin (DBT) also inhibited steroidogenesis by the follicles while monobutyltin and tetrabutyltin had negligible effects. The toxic effect of TBT or DBT was irreversible and a short time of exposure (30 min) was enough to suppress steroidogenesis. All the phenyltin compounds significantly inhibited FPH-induced $P_5$ synthesis by the follicles. The effective dose of 50% inhibition by diphenyltin was $0.04\;{\mu}M$ and those of monophenyltin and triphenyltin were $0.24\;{\mu}M$ and $0.3\;{\mu}M$, respectively. However, none of the phenyltin compounds significantly suppressed the conversion of $P_4$ to $17{\alpha}$-hydroxyprogesterone ($17{\alpha}$-OHP) (by $17{\alpha}$-hydroxylase), $17{\alpha}$-OHP to androstenedione (AD) (by $C_{17-20}$ lyase), or AD to testosterone by the follicles. Taken together, the data show that among the steroidogenic enzymes, P450scc in the follicles is the most sensitive to organotin compounds and that an amphibian follicle culture system can be a useful screening model for endocrine disruptors.

• Clinical and Experimental Reproductive Medicine
• /
• 제42권2호
• /
• pp.67-71
• /
• 2015

Objective: Elevated serum progesterone (P) levels on triggering day have been known to affect the pregnancy rate of in vitro fertilization (IVF). This study aimed to identify the possible factors influencing serum P levels on triggering day in stimulated IVF cycles. Methods: Three hundred and thirty consecutive fresh IVF cycles were included in the study. All cycles were first attempts and were performed in a single infertility center. The indications for IVF were male factor infertility (n=114), ovulatory infertility (n=84), endometriosis (n=61), tubal infertility (n=59), unexplained infertility (n=41), and uterine factor infertility (n=39). A luteal long protocol of a gonadotropin-releasing hormone (GnRH) agonist (n=184) or a GnRH antagonist protocol (n=146) was used for pituitary suppression. Ovarian sensitivity was defined as the serum estradiol level on triggering day per 500 IU of administered gonadotropins (OS[a]) or the retrieved oocyte number per 500 IU of administered gonadotropins (OS[b]). Results: Univariate analysis revealed that the serum P level on triggering day was associated with the serum estradiol level on triggering day (r=0.379, p<0.001), the number of follicles ${\geq}14mm$ (r=0.247, p<0.001), the number of retrieved oocytes (r=0.384, p<0.001), and ovarian sensitivity (OS[a]: r=0.245, p<0.001; OS[b]: r=0.170, p=0.002). The woman's age, body mass index, antral follicle count, and basal serum follicle stimulating hormone and estradiol levels were not associated with serum P level on triggering day. The serum P level on triggering day did not show significant variation depending on the type or cause of infertility, pituitary suppression protocol, or the type of gonadotropins used. Conclusion: The serum P level on triggering day was closely related to the response to ovarian stimulation.

• Asian-Australasian Journal of Animal Sciences
• /
• 제15권7호
• /
• pp.1045-1050
• /
• 2002

The aims of this study were to detect spontaneously occurring apoptosis in cultured porcine ovarian cells, to examine the role of growth hormone (GH), tyrosine kinase (TK), protein kinase G (PKG) and cyclin-dependent kinase (CDK) in the control of this process, and to determine whether the effect of GH on apoptosis is mediated by TK-, PKG- and cdc2-dependent intracellular mechanisms. We studied the action of pGH (10 ng/ml), blockers of TK (genistein, lavendustin, both 100 ng/ml), PKG (Rp-Br-PET-cGMPS, 50 nM; KT5823, 100 ng/ml) and CDK (olomoucine, $1{\mu}g/ml$), as well as combinations of GH with these blockers, on the onset of apoptosis in cultured granulosa cells isolated from antral (3-6 mm) porcine follicles. The functional characteristics of an early apoptotic event, DNA fragmentation, were determined using terminal deoxynucleotidyltransferase (TdT)-mediated dUTP nick end labelling (TUNEL), whilst morphological signs of advanced apoptosis such as pyknosis, chromatin marginalization, shrinkage and fragmentation of nucleus, were detected using routine light microscopy. After culture, some ovarian granulosa cells exhibited DNA fragmentation, which in some cases was associated with morphological apoptosis-related changes (pyknosis, shrinkage and fragmentation of the nucleus). GH significantly reduced the proportion of TUNEL-positive cells. Neither TK nor CDK blockers when given alone, significantly affected the percentage of TUNEL-positive cells although both PKG blockers significantly increased this index. Furthermore, TK and PKG blockers given together with GH, prevented or reversed the inhibitory effect of GH on apoptosis, whilst the CDK blocker olomoucine promoted it. These observations demonstrate apoptosis in porcine ovaries and suggest the involvement of GH, TK, PKG and CDK in the control of this process. They also suggest that the effect of GH on ovarian apoptosis is mediated or regulated by multiple signalling pathways including TK-, PKG- and CDK-dependent intracellular mechanisms.

• Asian-Australasian Journal of Animal Sciences
• /
• 제29권8호
• /
• pp.1065-1074
• /
• 2016

Growth factors play an important role during early ovarian development and folliculogenesis, since they regulate the migration of germ cells to the gonadal ridge. They also act on follicle recruitment, proliferation/atresia of granulosa cells and theca, steroidogenesis, oocyte maturation, ovulation and luteinization. Among the growth factors, the growth differentiation factor 9 (GDF9) and the bone morphogenetic protein 15 (BMP15), belong to the transforming growth factor beta (TGF-${\beta}$) superfamily, have been implicated as essential for follicular development. The GDF9 and BMP15 participate in the evolution of the primordial follicle to primary follicle and play an important role in the later stages of follicular development and maturation, increasing the steroidogenic acute regulatory protein expression, plasminogen activator and luteinizing hormone receptor (LHR). These factors are also involved in the interconnections between the oocyte and surrounding cumulus cells, where they regulate absorption of amino acids, glycolysis and biosynthesis of cholesterol cumulus cells. Even though the mode of action has not been fully established, in vitro observations indicate that the factors GDF9 and BMP15 stimulate the growth of ovarian follicles and proliferation of cumulus cells through the induction of mitosis in cells and granulosa and theca expression of genes linked to follicular maturation. Thus, seeking greater understanding of the action of these growth factors on the development of oocytes, the role of GDF9 and BMP15 in ovarian function is summarized in this brief review.

• 한국발생생물학회지:발생과생식
• /
• 제4권1호
• /
• pp.125-131
• /
• 2000

Differential display-PCR 방법을 이용하여, hCG 처리에 의한 참돔, Pagrus major의 난성숙 능력의 획득 경과시간에 따라 새롭게 발현하는 cDNA를 해석하였다. Differential display-PCR과 5'RACE 방법을 이용하여, 2,662 염기와 434개의 아미노산을 코드하고 있는 cDNA의 전염기배열을 결정하였다. DNA의 데 이터베이스인 GenBank 및 EMBL을 이용하여 상동성을 검색한 결과, 본 cDNA와 높은 상동성을 나타낸 유전자는 검색되지 않았다. 따라서 본 cDNA는 참돔의 난성숙 능력 유도와 함께 그 발현량이 증가하는 난성숙 관련 유전자로 판단되었다. 또한 본 cDNA에서는 protein kinase C 인산화 및 casein kinaseII 인산화 consensus 배열의 존재가 확인되었다. 본 연구에서 cloning된 난성숙 관련 유전자는 난여포에 hCG 처리 9～24시간 후에 그 발현량이 증가하였으며, GH-II (300 ng/ml)로 배양한 난여포에서 특이적으로 증가하였다. 또한 in vivo 실험에서 난성숙 관련 유전자는 난성숙 능력 획득 이전의 난소에서는 거의 발현하지 않았으나, 난성숙 능력을 획득한 난소에서 강하게 발현된 점으로 보아, hCG에 의한 난성숙 능력 유도에 성숙기간 중 새롭게 합성되는 난성숙 관련 유전자가 관여할 가능성이 높다.

• Clinical and Experimental Reproductive Medicine
• /
• 제39권3호
• /
• pp.107-113
• /
• 2012

Objective: To determine whether animal age impacts in vitro preantral follicle growth. Effects of hCG, stem cell factor (SCF), and/or insulin-like growth factor (IGF) supplementation in growth medium were also investigated. Methods: Intact preantral follicles were mechanically isolated from fresh ovaries of BDF1 mice and cultured in growth medium for 9 to 11 days. Surviving follicles with antrum formation were transferred to maturation medium for 14 to 18 hours. Follicle survival, antrum formation, and retrieval of metaphase II (MII) oocytes were compared among three age categories (4-5, 7-8, and 10-11 week-old). By using 7- to 8-week-old mice, preantral follicles were cultured in growth medium supplemented with hCG (0, 5, or 10 mIU/mL), SCF (50 ng/mL), IGF-1 (50 ng/mL), and SCF+IGF-1. Results: Seven- to eight-week-old mice showed a higher follicle survival and antrum formation and produced more MII oocytes compared to other groups. In the 7- to 8-week-old mice, supplementation of 5 mIU/mL hCG significantly enhanced the antrum formation but the percentage of MII oocytes was similar to that of the control. Supplementation of SCF+IGF-1 did not enhance follicle survival or antrum formation but the percentage of MII oocytes increased modestly (39.1%) than in the control (28.6%, p>0.05, statistically not significant). Conclusion: Seven- to eight-week-old mice showed better outcomes in growth of preantral follicles in vitro than 4- to 5- or 10- to 11-week-old mice. Supplementation of hCG enhanced antrum formation and supplementation of SCF+IGF-1 yielded more mature oocytes; hence, these should be considered in the growth of preantral follicles in vitro.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권12호
• /
• pp.1711-1715
• /
• 2003

The experiment was designed on 42 non pregnant Black Bengal goat. Out of which 18 were subjected to a superovulatory treatment comprising of eCG and hCG for embryo transfer study. The remaining 24 goats received no treatment and served as control for parameter studied as well as recipient for embryo transfer studies. Important biochemical constituents such as acid and alkaline phosphatase, total protein and cholesterol and inorganic phosphorus were estimated in the follicular fluid of control and treated group and the values were separately recorded for small medium and large size follicle. The results indicated a significant effect on acid phosphotase activity due to size of follicle. The value increased progressively from small to medium and from medium to large follicles. Alkaline phosphotase activity showed reverse trend. Alkaline phosphotase decreased progressively as size increased. The concentration of inorganic phosphorus did not reveal any significant difference between the control and treatment groups and also between the different size follicles. The concentration of protein decreased significantly from small to medium and from medium to large, although no difference was observed between the control and treatment groups. The concentration of Cholesterol in the follicular fluid indicated a significant increase from small to medium and to large follicle. Here also no difference was observed due to treatment. Similar in the composition of follicular fluid in the respect of above mentioned constituents indicated no of super ovulatory treatment on follicular fluid composition.

• 한국동물학회지
• /
• 제33권2호
• /
• pp.152-157
• /
• 1990

면역조직화학적 방법을 이용하여 생쥐 난소에서 $\beta$-endorphin이 생성되는 부위를 조사하기 위하여 본 실험을 행하였다. 성숙한 생쥐를 4% neutral buffered paraformaldehyde로 관류고정하였으며 난소를 적출한 후 cryostat로 절편을 만들어 avidin-biotin complex(ABC)를 이용하여 면역색을 하였다. $\beta$-endorphin에 대한 항체반응은 주로 황체에서 일어났으며, theac interna와 theca externa에서는 반응이 나타나지 않았다. 황체에서의 염색 양상은 퇴화가 많이 진행된 황체세포에서 보다 강한 연색반응을 관찰할 수 있었다. 때로 황체세포에서 유래된 것으로 보이는 간질세포에서도 양성반응을 관찰할 수 있었다. 이외에도 large antral follicle의 여포강에 인접한 과립세포에서 약한 반응을 보여주었으나, 제 1차 여포에서는 양성반응이 나타나지 않았다.

• Reproductive and Developmental Biology
• /
• 제31권3호
• /
• pp.181-186
• /
• 2007

DNA 결합 단백질 억제(Inhibitor of DNA binding protein) 또는 분화억제(Inhibitor of differentiation) 인자인 Id는 네 종류(Id1-4)가 있으며, 세포의 증식과 분화, 혈관 형성 및 세포자가사멸 등에 정 또는 부의 조절인자로서 널리 알려져 있다. 하지만 아직까지 번식생리 분야에서 이들 유전자들의 발현이나 기능에 관해 알려진 것은 거의 없다. 따라서 본 연구에서는 쥐 난소에서 난포의 발달에 따른 Id3 mRNA의 발현 양상을 살펴보고자 실시하였다. 쥐에게 PMSG주사 후, 3, 6, 12, 24, 36 및 48시간째에 난소를 회수하여 고정, 탈수 및 파라핀 포매를 실시하였다. In situ hybridization 실험을 위하여 anti-sense와 sense Id3 cRNA 탐침자를 제작한 다음 난소 절편에 반응시켰다. 반응이 끝난 난소 절편은 NTB-2 유광제에 노출시킨 후 현상액에 반응시켰다. 모든 처리가 끝난 슬라이드는 H&E 염색을 실시한 다음 현미경하에서 hybridization 감도를 1+에서 4+로 구분하여 평가하였다. 난자에서는 Id3 mRNA 감도가 원시와 제1차 난포에서 ${\geq}2+$으로 확인되었으나, 제2차, 우성 및 배란전 난포에서는 1+ 이하로 관찰되었다. 한편, 과립막세포에서는 우성과 배란 전 난포에서 Id3 mRNA가 3+ 또는 4+로 강하게 발현되는 것을 확인하였다. 이상의 결과를 종합하여 보면, Id3 mRNA는 난포의 발단 단계 또는 난포세포에 따라 특이적으로 발현하는 것으로 보아 난포의 발달과 밀접한 연관이 있을 것으로 사료된다.

• 한국동물학회지
• /
• 제33권1호
• /
• pp.63-69
• /
• 1990

포유류의 난소내 여포의 폐쇄기작을 알아보기 위하여 본 실험을 행하였다. 정상과 폐쇄를 형태적으로 판정한 돼지의 난소내 개개 중여포의 여표액내 스테로이드 호르몬과 단백질을 방사면역측정법과 SDS-전기영동으로 각각 분석하여 다음과 같은 결과를 얻었다. Progesterone은 여포성숙기의 여포액내 폐쇄여포에서 높은 농도를 나타내었고testosterone의 경우 황체기의 정상여포 및 여포성숙기의 폐쇄여포에서 높은 농도를 나타내었다. estradiol은 여포성숙기의 폐쇄여포에서 정상여포에 비해 현저히 낮았다. 여포액내 존재하는 단백질의 SDS-PAGE 결과, 혈청에 존재하지 않는 4종의 단백질을 확인하였다. 난소주기에 따라 112K, 141K의 단백질이 확인되었고, 폐쇄여포액내 특이하게 존재하는 23K, 24K의 단백질도 확인할 수 있었다. 이상의 결과로 보아 난소주기에 따라 여포액재에 존재하는 스테로이드 호르몬의 농도와 단백질의 조성이 서로 같지 않음을 알 수 있었으며 여포의 폐쇄기작에 있어서도 난소주기에 따라 분명한 차이가 있음을 알 수 있었다. 그러나 이들 폐쇄여포에 존재하는 단백질들의 생리적인 역할을 이해하기 위하여는 많은 연구가 수행되어야 한다고 사료된다.