• 한국임상수의학회지
• /
• 제3권1호
• /
• pp.227-233
• /
• 1986

A total of 600 Holstein cows in Chonnam province was examined to make a diagnosis on the ovarian follicular cyst. By clinical signs and rectal examination, 57 cows were found to have ovarian follicular cyst. Attempts were made to treat the cows which had ovarian follicular cyst with GnRH, HCG respectively. The results obtained were summarized as follows : 1. The rates of estreous induction with GnRH or HCG were 91.4%, 77.2%, respectively. The GnRH treated group was showed significantly higher than HCG treated group. The mean days from the GnRH or HCG treated to estrum were 25.1 and 23.5 days, respectively. 2. The Conception rates with GnRH or HCG treatment were 78.2% and 76.5％, respectively. 3. Services per conception with GnRH or HCG treatment were 1.5 and 2.1 respectively. 4, Days from GnRH or HCG treatment to concept were 38.2 and 45.8 days, respectively. 5. Intramuscular injection with GnRH and intraovarian injection with HCG were revealed the most effective routes in all the other routes.

• Clinical and Experimental Reproductive Medicine
• /
• 제29권4호
• /
• pp.259-267
• /
• 2002

Objective: This study was performed to compare the clinical outcomes of GnRH antagonist (Cetrorelix) single dose and multiple dose protocols for controlled ovarian hyperstimulation with GnRH agonist long protocol. Materials and Method: From September 2001 to March 2002, 48 patients (55 cycles) were performed controlled ovarian hyperstimulation for ART using by either GnRH antagonist and GnRH agonist. Single dose of 3 mg GnRH antagonist was administered in 15 patients (17 cycles, single dose group) at MCD #8 and multiple dose of 0.25 mg of GnRH antagonist was administered in 15 patients (18 cycles, multiple dose group) from MCD #7 to hCG injection day. GnRH agonist was administered in 18 patients (20 cycles, control group) by conventional GnRH agonist long protocol. We compared the implantation rate, number of embryos, and clinical pregnancy rate among three groups. Student-t test and Chi-square were used to determine statistical significance. Statistical significance was defined as p<0.05. Results: There were no significant differences in ampules of used gonadotropins, number of mature oocytes, obtained embryos between single and multiple dose group, but compared with control group, ampules of used gonadotropins, number of mature oocytes, obtained embryos were decreased significantly in both groups. Clinical pregnancy rate and implantation rate were not different in three groups. There were no premature LH surge and ovarian hyperstimulation syndrome in three groups. Multiple pregnancy were occurred 1 case in multiple dose group and 2 case in control group. Conclusions: GnRH antagonist is a safe, effective, and alternative method in the controlled ovarian hyperstimulation compared with GnRH agonist. Clinical outcomes and efficacy of both single and multiple dose protocol are similar between two groups.

• 대한약리학회지
• /
• 제23권2호
• /
• pp.57-75
• /
• 1987

Two modalities of gonadotropin secretion, pulsatile gonadotropin and preovulatory gonadotropin surge, have been identified in the mammals. Pulsatile gonadotropin secretion is modulated by the pulsatile pattern of GnRH release and complex ovarian steroid feedback actions. The neural mechansim that regulates the pulsatile release of GnRH in the hypothalamus is called "GnRH pulse generator". Ovarian steroids, estradiol and progesterone, appear to exert thier feedback effects both directly on the pituitary to modulate gonadotropin release and on a hypothalamic site to modulate GnRH release; estradiol primarily affects the amplitude while progesterone decreases the frequency of the pulsatile GnRH. Steroid hormones are known to affect catecholamine transmission in brain. MBH-POA is richly innervated by NE systems and close apposition of NE terminals and GnRH cell bodies occurs in the MBH as well as in the POA. NE normally facilitates pulsatile LH release by acting through ${\alpha}-receptor$ mechanism. However, precise nature of facilitative role of NE transmission in maintaining pulsatile LH has not been clearly understood. Close apposition of DA and GnRH terminals in ME might permit DA to influence GnRH release. Action of DA transmission probably is mediated by axo-axonic contacts between GnRH and DA fibers in the ME. Dopamine transmission does not normally regulate pulsatile LH release, but under certain conditions, increased DA transmission inhibit LH pulse. Endogenous opioid acts to suppress the secretion of GnRH into hypophysial portal circulation, thereby inhibiting gonadotropin secretion. However, an interaction between endogenenous opioid peptides and gonadotropin release is a complex one which involves ovarian hormones as well. LH secretion appears to be most suppressed by endogenenous opioids during the luteal phase, at a time of elevated progesterone secretion. The arcuate nucleus contains not only cell bodies for GnRH and ${\beta}-endorphin$ but also a dense aborization of fibers suggesting that GnRH release is changed by the interactions between GnRH and ${\beta}-endorphin$ cell bodies within the arcuate nucleus. The frequency and amplitude of pulsatile LH release seem to be increased during the preovulatory gonadotropin surge. Estradiol exerts positive feedback action on the hypothalamo-pituitary axis to trigger preovulatory LH surge. GnRH is also crucial hormonal stimulus for preovulatory LH surge. It is unlikely, however, that increased secretion of GnRH during the preovulatory gonadotropin surge represents an obligatory neural signal for generation of the LH discharge in primates including human. Modulation of preovulatory LH surge by catecholamines has been studied almost exclusively in rats. NE and E may be involved in distinct way to accumulate GnRH in the MBH and its release into the hypophysial portal system during the critical period for LH surge on proestrus in rats. However, the mechanisms whereby augmented adrenergic transmission may facilitate the formation and accumulation of GnRH in the ME-ARC nerve terminals before the LH surge have not been clearly understood.

• Clinical and Experimental Reproductive Medicine
• /
• 제37권3호
• /
• pp.239-244
• /
• 2010

목 적: 본 후향적 연구는 성선자극호르몬분비호르몬 작용제 (gonadotropin-releasing hormone [GnRH] agonist)와 길항제 (GnRH antagonist) 치료를 받은 불량반응군의 결과를 비교, 분석하고자 하였다. 연구방법: 총 172회의 체외수정시술 주기에서 GnRH agonist 또는 antagonist protocol로 과배란유도를 시행받고 채취된 난자의 수가 5개 이하인 불량반응군을 대상군으로 하였다. 난포 및 채취된 난자의 수, 수정률 등의 결과를 두 군 간에 비교하였다. 결 과: GnRH agonist long protocol과 antagonist protocol 두 군 간에 난포 및 난자의 수와 수정률은 차이를 보이지 아니하였다. 반면, 과배란유도 제7/8일의 혈중 $E_2$ 농도는 GnRH antagonist군에서 더 높았던 반면, 사용한 평균 성선자극호르몬의 용량은 유의하게 적고 과배란유도 기간은 짧은 것을 확인할 수 있었다 (각각 p<0.01). 결 론: 불량 반응군에서 GnRH agonist long protocol에 비하여 GnRH antagonist protocol의 경우 노력이 상대적으로 적게 필요한 반면 비슷한 임상적 결과를 고려할 때, GnRH antagonist protocol이 상대적으로 우수한 것으로 생각된다.

• Animal cells and systems
• /
• 제2권4호
• /
• pp.483-488
• /
• 1998

We previously found that a potent gonadotropin-releasing hormone (GnRH) agonist, buserelin, decreases GnRH promoter activity together with GnRH mRNA level, providing evidence for an autoregulatory mechanism operating at the level of GnRH gene transcription in immortalized GT1-1 neuronal cells. To examine whether agonist-induced decrease in GnRH mRNA level requires the continuous presence of buserelin, we performed a pulse-chase experiment of buserelin treatment. Short-term exposure (15 min) of GT1-1 neuronal cells to buserelin ($10{\mu}M$) was able to decrease GnRH mRNA levels when determined 24 h later. When GT1-1 cells were treated with buserelin ( $10{\mu}M$) for 30 min and then incubated for 1, 3, 6, 12, 24, and 48 h after buserelin removal, a significant decrease in GnRH mRNA levels was observed after the 12 h incubation period. These data indicate that inhibitory signaling upon buserelin treatment may occur rapidly, but requires a long time (at least 12 h) to significantly decrease the GnRH mRNA level. To examine the possible involvement of de novo synthesis and/or mRNA stability in buserelin-induced decrease in GnRH gene expression, actinomycin D ($5{\mu}m/ml$), a potent RNA synthesis blocker, was co-treated with buserelin. Actinomycin D alone failed to alter basal GnRH mRNA Revel, but blocked the buserelin-induced decrease in GnRH mRNA level at 12 h of post-treatment. These data suggest that buserelin may exert its inhibitory action by altering the stability of GnRH mRNA. Moreover, a polvsomal RNA separation by sucrose gradient centrifugation demonstrated that buserelin decreased the translational efficiency of the transcribed GnRH mRNA. Taken together, these results clearly indicate that GnRH agonist buserelin acts as an inhibitory signal at multiple levels such as transcription mRNA stability, and translation.

• 한국동물학회지
• /
• 제37권4호
• /
• pp.504-513
• /
• 1994

The present study was carried out 1) to show the ontogenic development of CA-and GnRH-containing nerve fobres in the median eminence, 2) to simultaneously demonstrate the synaptic contact between these two nenre fibres in the rat median eminence at the ultrastructural level using light and electron microscopic doublelabel immunostainlngs. GnRH-and CA-nenre terminals were detectable in the median eminence at embryonic day 19.5. The CA-newe terminals were obsenred in the entire legion of the extern31 lavers, while GnRH-newe terminals only in the lateral portion. At the 14th postnatal daw, both %ropes of nerve terminals showed a very similar distribution to those of adult one. In the median eminence of adult rats, a substantial overlap existed in the distribution of GnRH fibres with CA-containing nerve fibres. This overlap was most intense throughout the external palisade zone. Furthermore, an electron microscopic double label immunostaining showed that there was a close apposition of CA- and GnRH-nenre fobres. These axo-axonic contacts occurred frequently in the internal and palisade zones, i.e. at the level of the fobre preterminals. These morphological results suggest that the CA-mediated GnRH secretion may occur via sxo-axonic interaction in the median eminence.

• 한국수정란이식학회지
• /
• 제18권3호
• /
• pp.187-193
• /
• 2003

본 연구는 한우에 GnRH ＋ PGF$_2$$\alpha$＋GnRH (Ov-synch)를 처리하여 배란동기화를 시켰으며, 2차 GnRH 투여후 배란시간, 수태율, 계절별 수태율, 산차별 수태율을 조사하였으며, 시험축은 2산 이상의 개체를 무작위로 선발하여 실험에 공시하였으며, 배란동기화 처리후 1회 인공수정을 실시하고 수태율을 환산하였다. 호르몬 처리방법으로는 GnRH ＋ PGF$_2$$\alpha$ ＋ Gn-RH(Ov-synch)법을 이용하였으며, 배란시간의 조사는 초음파를 이용하여 2차 GnRH 투여 후 24시간부터 31시간까지 2시간 간격으로 난소를 촬영하여 배란 여부를 조사하였다. 1. 배란동기화 처리후 24시간부터 31시간까지 2시간 간격으로 난소의 상태를 확인한 결과 28∼30시간 사이에 80%(20/25)로 가장 많이 배란된 것으로 나타났다. 2. 수태율에 있어서는 계통별 1회 수정 수태율은 고급육 계통이 48.1%(38/79)로 다소 높게 나타났다. 3. 산차에 따른 수태율은 1∼2, 3∼4산차에서 각각 44.3, 55%로 나타났다. 4. 계절별로는 여름보다는 봄과 가을에서 47.3%로 다소 높은 경향이였다.

• 한국수산과학회지
• /
• 제32권3호
• /
• pp.266-270
• /
• 1999

성숙 점농어 뇌에서 세 종류의 생식소자극호르몬 분비호르몬 (GnRH)의 소재를 면역조직화학법에 의해 동정하였다. sGnRH 양성 신경세포체는 후각망울, 복측 종뇌와 전시각 지역에 분포하였다. 양성 신경섬유는 후각망울에서부터 척수에 이르기까지 다양하게 분포하였다. 면역신경섬유는 뇌의 전지역인 후각망울, 종뇌, 시각시개, 소뇌, 연수 그리고 머리쪽 척수에서 발견되었다. 대부분의 경우 이들은 모두 다발을 형성하지는 않았다. 그러나 후각망울에서 뇌하수체로 뻗어있는 양성 신경섬유는 가장 뚜렷하였다. cGnRH-II 양성 신경세포체는 후엽에서 발견되었다. 그러나 cGnRH-II 면역신경섬유도 후각망울에서 뇌하수체로 뻗은 면역신경섬유를 제외하고는 기본적으로 sGnRH 양성 신경섬유와 분포가 유사했다. 이것은 점농어 뇌에서 sGnRH와 cGnRH-II가 알려진 내인성 펩타이드이며, 이들이 다양한 신경내분비 기능을 수행할 것이라는 점을 의미한다. sGnRH는 GTH의 분비를 조절 할 뿐만 아니라 신경전달조절자로서, cGnRH-II는 단지 신경전달조절자로서 작용할 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제11권4호
• /
• pp.416-421
• /
• 1998

The objective of this study was to investigate the responsiveness of hypophysis and gonads to synthetic GnRH among noncycling Murrah buffalo heifers at 24 months of age. The plasma FSH, LH, estradiol and progesterone levels were measured in blood samples collected at 1 hour before and upto 18th day subsequent to the administration of GnRH ($(200 {\mu}g)$) or saline (2 ml). The pretreatment levels of plasma FSH, LH estradiol and progesterone among GnRH treated heifers (N = 6) were $11.55{\pm}0.57ng/ml$, $0.68{\pm}0.06ng/ml$, $19.84{\pm}0.82pg/ml$ and $0.45{\pm}0.07ng/ml$ respectively. A quick elevation of FSH (p < 0.01) and LH (p < 0.05) within 5 min of GnRH administration was observed in all the heifers. The peak FSH ($74.97{\pm}18.63ng/ml$) and LH ($3.09{\pm}0.54ng/ml$) level was obtained at 30 min of GnRH administration. The elevated level of plasma estradiol on 5th to 18th day, FSH on 7th to 9th day (n = 3) and the progesterone on 13th to 18th day (n = 2) of GnRH injection was obtained. The study indicates that gonads of buffalo heifers at 24 months of age are responsive of GnRH induced gonadotropin release for folliculogenesis and luteal tissue formation

• 한국발생생물학회지:발생과생식
• /
• 제7권1호
• /
• pp.49-56
• /
• 2003

높은 농도로 투여된 성선자극호르몬 분비호르몬 이성체(GnRH-Ag)는 성선자극호르몬의 분비를 억제시키고 난소의 기능을 억제하는 하는 것으로 보고되고 있다. 그러나 체외수정 및 배아이식 시술과정에서 과배란 유도를 위해 다량의 GnRH-Ag를 사용하고 있으며, 이는 progesterone을 보충해 주어야 하는 황체기 결함을 유발시킨다. 본 실험의 목적은 이러한 황체기 결함을 유발시키는 원인을 알아보고자 사람 과배란 유도 과정과 비슷하게 생쥐에 GnRH-Ag와 PMSG를 투여하고 난소내 세 포자연사와 호르몬 합성 의 변화를 조사하고자 하였다. GnRH-Ag과 생리 식염수를 PMSG 투여 전 48시간부터 투여 후 48시간까지 12시간 간격으로 10$\mu$g씩 주사한 후 난소와 혈액을 채취하였다. 결과로서 난소의 무게는 GnRH-Ag만을 투여한 군에서 다른 두 실험군(PMSG 투여군, PMSC + CnRH-Ag 투여군)에 비해 유의하게 감소하였다. GnRH-Ag 투여군에서 난소내 강소형성전 난포의 비율은 증가한 반면, PMSC + GnRH-Ag투여군에서는 강소형성 난포의 비율은 감소하였고 황체의 비율은 증가하였다. 한편 난소내 세포자연사를 보이는 난포의 비율은 GnRH-Ag 투여군에서 PMSG 투여군에 비해 두배 이상 증가한 것을 알 수 있었고, 이러한 증가는 PMSC를 함께 투여함으로서 감소하는 것을 알 수 있었다. 혈청내 estradiol과 progesterone의 농도는 GnRH-Ag 투여군에서 다른 두군에 비해 유의하게 감소하였다. 그러나 GnRH-Ag와 함께 PMSG를 투여 한 경우 estradiol 농도는 PMSG 투여군 수준까지 완전히 회복되었으나, progesterone농도는 완전히 회복되지 않았다. 결론적으로 체외수정 및 배아이식 과정에서 사용되는 GnRH-Ag는 난소내 세포자연사를 유발하고 호르몬 합성을 억제시켜 황체기 결함을 유발시킬 수 있으며, 이를 막기 위해 적절한 progesterone 보충이 필요한 것으로 사료된다.