• Asian-Australasian Journal of Animal Sciences
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• 제22권8호
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• pp.1113-1116
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• 2009

The objective of this study was to compare the follicular population during spontaneous and $PGF_2{\alpha}$ induced oestrous cycles in Nili-Ravi buffaloes. In Exp.1, (n = 13 oestrous cycles) follicular population was monitored using ultrasonography on alternate days. Buffaloes were monitored for ovarian follicles from day 0 (first oestrus) until next oestrus. These animals were observed for oestrus twice daily using a teaser bull. Of 12 oestrous cycles, 9 (75%) had two waves of follicular activity and only 3 (25%) had three waves during the oestrous cycle. The mean number of small, medium and large follicles among various days of the oestrous cycle between two and three waves of follicular development were not significantly different (p>0.05). In Exp. 2, follicular population 3 days before oestrus was compared in buffaloes undergoing spontaneous (n = 12 oestrous cycles) and $PGF_2{\alpha}$ induced (n = 6) luteolysis. The mean number of small and large follicles increased (p<0.05) and the number of medium follicles decreased (p<0.05) during the 3 days before oestrus in buffaloes undergoing induced luteolysis as compared to those with spontaneous luteolysis. These results showed that the mean number of small, medium and large follicles among various days of the oestrous cycle were similar between the two and three waves of follicular development, and three days before oestrous the number of small, medium and large follicles altered due to induced luteolysis on day 9, compared to those with spontaneous luteolysis.

• 한국수정란이식학회지
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• 제15권1호
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• pp.77-83
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• 2000

The purpose of this study was to develop a breeding technique to increase Hanwoo of superior characteristics. In the present study, reproductive status of Hanwoo such as size of farm, breeding system and gestationi length was investigated. In addition, effect of low dose administration of prostaglandin F2$\alpha$(PGF2$\alpha$) on luteolysis was examined. The size of farm was classified by the total number of cows and the number of breeding stocks, respectively. The distribution of herd size of < 5, 6~10, 11~30, 31~50 and > heads was 31%, 15%, 39%, 4% and 11%, respectively. Furthermore, the distribution of breeding stock size of <5, 6~10, 11~30, 31~50 and > 50 heads was 36%, 28%, 31%, 3% and 3%, respectively. Average parity was 2.1 in breeding stock. In breeding pattern, artificial in semination(A.I), estrus synchronization-A.I and natural mating was 92.7%, 2.4% and 4.9% respectively. Gestational length of Hanwoo was ranged 253~316 days (average length : 285 days) after estrus( estrus=0). To induce luteolysis, PGF2$\alpha$ was injected into ovarian parenchyma by a modified ovarian injector. The effect of administration of 6mg PGF2$\alpha$ on luteolysis and estrus induction was betweer (P<0.01) when PGF2$\alpha$ was administered into ovarian parechyma than when administered intramuscluarly (71 vs. 91%). When PGF2$\alpha$ was injected into ovarian parenchyma, a decreased concentration to 3 mg did not significantly decreaed its luteolytic effect(92%). When AI was performed following PGF2$\alpha$ treatment, the intraovarian injection group yielded a higher pregnancy rate(69 vs. 88%) than the IM injection groups, regardless of the dosage. In conclusion these results suggest that increasing herd size and regular reproductive management are needed to improve reproductive efficiency in Hanwoo industry. Furthermore, intraovarian administration of PGF2$\alpha$ is effective way to induce luteolysis compared with intramuscular injection.

• Journal of Animal Science and Technology
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• 제48권2호
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• pp.191-202
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• 2006

황체내에서 대식세포는 자신이 분비하는 사이토카인을 통해 황체형성기에는 황체형성세포들의 증식과 성장에 관여하고 황체용해시기에는 황체세포들의 아포토시스와 그들의 제거에 직간접적으로 관여하는 것으로 알려져 있다. 본 실험에서는 돼지에서 최대성숙황체 시기와 황체의 용해에 따른 대식세포의 역할과 작용기전 등을 알아보기 위해 면역조직화학적 및 투과전자현미경적 방법으로 황체의 형태학적 변화를 관찰하였다. 그 결과 돼지에서는 황체용해시에 아포토시스 소체들을 포식하는 대식세포들이 관찰되지 않았고, 최대 황체시기와 황체용해시기에 대식세포들은 미세구조와 그것들이 위치하는 부위가 각기 다른 2가지 아형들이 관찰되었다. 이같은 결과로 볼 때, 돼지에서는 황체용해시 아포토시스 소체들이 대식세포의 포식작용에 의하지 않고 자체 혈관을 통해 제거되는 것으로 보이며, 황체에는 각 시기별로 각기 다른 임무를 띤 아형의 대식세포들이 혈류로부터 들어와 시기특이적으로 작용하는 것으로 추정된다.

• Reproductive and Developmental Biology
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• 제39권1호
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• pp.1-6
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• 2015

Luteolysis is a cyclical regression of the corpus luteum in many non-primate mammalian species. Prostaglandin $F_2{\alpha}$($PGF_2{\alpha}$) from the uterus and ovary induces functional and structural luteolysis in bovine. The action of $PGF_2{\alpha}$ is mediated by $PGF_2{\alpha}$ receptor located on the luteal steroidogenic and endothelial cell membranes. $PGF_2{\alpha}$ plays an important role in regulating nitric oxide production in endothelial cells of the bovine corpus luteum. Nitric oxide production and nitric oxide synthase activity are stimulated and induced by $PGF_2{\alpha}$ in luteal endothelial cells. Moreover, the reactive oxygen species inhibits progesterone secretion in bovine luteal cells and induces apoptosis. Thus, the interaction between $PGF_2{\alpha}$ and reactive oxygen species provides important aspects in physiology of the corpus luteum forfunctional and structural luteolysis.

• Clinical and Experimental Reproductive Medicine
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• 제35권1호
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• pp.61-67
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• 2008

목 적: Glucocorticoid가 황체용해에 미치는 효과의 기전의 일부를 면역 조직학적 연구를 통해 알아보고자 하였다. 연구방법: 8주령의 Rat 암컷 30마리 대조군, 덱사메타손 0.1 mg 투여군 및 덱사메타손 1mg 투여군의 3군으로 나누어 황체용해의 차이와 대식세포의 침투여부를 비교하기 위하여 광학현미경을 이용하여 계수하였다. 결 과: TUNEL 면역염색 결과 덱사메타손 0.1 mg 투여군과 1 mg 투여군 모두에서 대조군에 비해 황체용해의 비율이 현저히 감소하였고, ED1 면역염색 결과 덱사메타손 1 mg 투여군에서 대식세포의 황체 내 침투가 현저히 억제된 것으로 나타났다. ED1 면역염색 결과 덱사메타손 1 mg 투여군에서 대식세포의 면역반응성이 대조군에 비해 감소되어 나타났다. 결 론: 덱사메타손은 직접 황체세포에 작용하여 세포자멸사를 억제한다. 또한 대량 투여했을 때는 대식세포의 황체 내 침투를 억제하거나 황체 내에 이미 존재하는 대식세포의 활성화를 억제함으로써 황체용해를 억제한다.

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2001년도 The Asia-Pacific Conference on Reproductive Biology and Environmental Sciences
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• pp.23-26
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• 2001

• 한국식품위생안전성학회:학술대회논문집
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• 한국식품위생안전성학회 2001년도 The Asia-Pacific Conference on Reproductive Biology and Environmental Sciences
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• pp.213-218
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• 2001

• Reproductive and Developmental Biology
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• 제37권3호
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• pp.149-154
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• 2013

The aim of this study was to evaluate the changes of protein patterns in granulosa cells and corpus luteum in ovaries during the estrus cycle in cows. The estrus cycle was devided into five steps of follicular, ovulatory, early-luteal, mid-luteal and late-luteal phases. In results, 61 spots of total 85 spots were repeated on follicular phase and 51 spots of total 114 spots were repeated on ovulatory phase. The 40 spots of total 129 spots were repeated on early-luteal phase and 49 spots of total 104 spots were repeated on mid-luteal phase. Also 41 spots of total 60 spots were repeated on late-luteal phase. On the other hands, the 16 spots were indicated difference in follicular phase and ovulation phase had a difference 10 spots. It was showed difference No. 103 spot in ovulation phase, No. 135 spot in early-luteal phase and No. 175 and 176 spots in mid-luteal phase. Also, the 11 spots were expressed specifically in mid-luteal phase and No. 178 and 179 spots were difference of expression in late-luteal phase. We confirmed that there were 7 spots for ovulation, 4 spots for luteinization and 2 spots for luteolysis. Spot No. 89~93 in ovulation phase were transferrin, and spot No.94~98 were HSP60. Spot No. 103 was Dusty PK, spot No. 135 was OGDC-E2, and spot No. 175 and 176 were Rab GDI beta from luteinization. Spot No. 178 and 179 in luteolysis were vimentin. This results suggest that will be help to basic data about infertility.

• 한국가축번식학회지
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• 제23권4호
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• pp.365-369
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• 1999

Interferon tau (IFN$\tau$), the pregnancy recognition signal in ruminants, suppresses transcription of the estrogen receptor (ER) gene in the endometrial luminal (LE) and superficial glandular epithelium (sGE) to prevent oxytocin receptor (OTR) expression and pulsatile release of luteolytic prostaglandin $F_{2{\alpha}}$ (PGF), Interferon regulatory factors one (IRF-l) and two (IRF-2) are transcription factors induced by IFN$\tau$ that activate and silence gene expression, respectively. Available results suggest that IFN$\tau$ acts directly on LE and sGE during pregnancy to induce sequentially IRF-l and then IRF-2 gene expression to silence transcription of ER and OTR genes, block the luteolytic mechanism to maintenance a functional corpus luteum (CL) and, signal maternal recognition of pregnancy. The theory for maternal recognition of pregnancy in pigs is that the uterine endometrium of cyclic gilts secretes PGF in an endocrine direction, toward the uterine vasculature for transport to the CL to exert its luteolytic effect. However, in pregnant pigs, estrogens secreted by the conceptuses are responsible, perhaps in concert with effects of prolactin and calcium, for exocrine secretion of PGF into the uterine lumen where it is sequestered to exert biological effects and / or be metabolized to prevent luteolysis.

• 대한의생명과학회지
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• 제19권3호
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• pp.180-187
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• 2013

Hypoxia is an integral part of the environment during luteolysis. In this study we examined whether hypoxia could directly stimulate endothelial cells to produce nitric oxide (NO). Endothelial cells were cultured in hypoxic (5% $O_2$) or normoxic (20% $O_2$) conditions and the levels of total NO, inducible NO and endothelial NO was measured. We found that hypoxia but not normoxia upregulated NO production. The increased NO levels correlated with increased inducible NO synthase (iNOS) expression whereas expression of endothelial NOS (eNOS) expression remained constant. Addition of the iNOS specific inhibitor 1400W to hypoxic cultures prevented NO production suggesting that hypoxia-induced NO production in endothelial cells was due mainly to upregulation of iNOS. We also found that prostaglandin $F_{2{\alpha}}$ (PGF) production was unaffected by hypoxia suggesting that upregulation of NO was not due to increased synthesis of PGF. In summary, we report that endothelial cells cultured under hypoxic conditions produce NO via the iNOS pathway. This study provides the importance of the relation between the hypoxic environment and the induction of NO by endothelial cells during regression of the corpus luteum in the ovary.