• The Korean Journal of Zoology
• /
• v.37 no.2
• /
• pp.161-173
• /
• 1994

면역효소법을 이용하여 3종의 한국산 개구리 참개구리(Rono nigromaculuto), 옴개구리(R. rugosa), 북방산개구리(R. 겨대bowskii)의 뇌에서 GnRH 뉴우런의 분포 부위와 GnRH의 종류 등을 연구하였다. 1차 항체로는 anti-rat GnRH, anti-salmon GnRH anti-chicken 11 GnRH 항체를 사용하였다. 3종의 개구리에서 mGnRH cGnRH 11와 sGnRH가 이둔 동정되었으나 3가지 항체에 대한 각 종의 면역 반응성은 종에 따라 달리 나타났다 mGnRH는 옴개구리와 참개구리에서, sGnRH는 북방산개구리에서 강한 면역 반응을 나타냈으며 cGnRH 11는 3종의 개구리에서 중간 정도의 면역 반응을 나타냈다. 각각의 GnRH의 상대적인 양에는 차이가 있으나 일부 경우를 제외하고는 뇌의 동일한 지역에 분포하였다. 참개구리에서는 GnRH가 중격 내측핵(NMS), Broca band 핵(NDB)에 집단으로 분포하였다. 북방산개구리에서는 GnRH가 중격 내측핵, Broca bnad 핵에서 등쪽에서 배쪽으로 길게 선상으로 가장 협소하게 분포하였으며, 번식기와 직전(1월-3월)에만 면역 반응을 나타냈다. 옴개구리의 뇌에서 가장 광범위한 지역, 즉 종뇌의 중격 내측핵, Broca band 핵, 아래 교차 지역(SCA)과 간뇌에 GnRH 신경세포가 분포하였으며. 제3뇌실 맥락얼기에서 mGnRH 신경세포가 처음으로 동정되었다. 3종에서 공통적으로 중격 내측핵과 Broca band 핵에서 유래한 신경섬유는 복측 시상하부를 거쳐 정중융기에 이르렀다. 이러한 결과는 GnRH가 뇌하수체에서 생식소 자극 호르몬의 분비 조절에 밀접한 관계가 있음을 뜻한다.

• 대한생식의학회:학술대회논문집
• /
• 2002.11a
• /
• pp.23-30
• /
• 2002

• Animal cells and systems
• /
• v.11 no.2
• /
• pp.93-98
• /
• 2007

Gonadotropin-releasing hormone (GnRH), synthesized in the hypothalamus, plays a pivotal role in the regulation of vertebrate reproduction. Since molecular isoforms of GnRH and their receptors (GnRHR) have been isolated in a broad range of vertebrate species, GnRH and GnRHR provide an excellent model for understanding the molecular co-evolution of a peptide ligand-receptor pair. Vertebrate species possess multiple forms of GnRH, which have been created through evolutionary mechanisms such as gene/chromosome duplication, gene deletion and modification. Similar to GnRHs, GnRH receptors (GnRHR) have also been diversified evolutionarily. Comparative ligand-receptor interaction studies for non-mammalian and mammalian GnRHRs combined with mutational mapping studies of GnRHRs have aided the identification of domains or motifs responsible for ligand binding and receptor activation. Here we discuss the molecular basis of GnRH-GnRHR co-evolution, particularly the structure-function relationship regarding ligand selectivity and signal transduction of mammalian and non-mammalian GnRHRs.

• Animal cells and systems
• /
• v.13 no.4
• /
• pp.429-437
• /
• 2009

The control mechanism of gonadotropin-releasing hormone (GnRH) on gonadotropin (GTH) release was studied using cultured pituitary cell or cultured whole pituitary obtained from Testosterone (T) treated and control immature rainbow trout. The release of FSH was not changed by salmon type GnRH (sGnRH), chiken-II type (cGnRH-II), GnRH analogue ([des-$Gly^{10}D-Ala^6$] GnRH ethylamide) and GnRH antagonist ([Ac-3, 4-dehydro-$Pro^1$, D-p-F-$Phe^2$, D-$Trp^{3,6}$] GnRH) in cultured pituitary cells of T-treated and control fish. Indeed, FSH release was not also altered by sGnRH in cultured whole pituitary. All tested drugs had no effect on the release of LH in both culture systems of control fish. The levels of LH, in contrast, such as the pituitary content, basal release and responsiveness to GnRH were increased by T administration in both culture systems. In addition, the release of LH in response to sGnRH or cGnRH-II induced in a dose-dependent manner from cultured pituitary cells of T-treated fish, but which is not significantly different between in both GnRH at the concentration examined. Indeed, LH release was also increased by sGnRH in cultured whole pituitary of T-treated fish. GnRH antagonist suppressed the release of LH by sGnRH ($10^{-8}\;M$) and GnRH analogue ($10^{-8}\;M$) stimulation in a dose-dependent manner from cultured pituitary cells of T-treated fish, and which were totally inhibited by $10^{-7}\;M$ GnRH antagonist. These results indicate that the sensitivity of pituitary cells to GnRH is elevated probably through the T treatment, and that GnRH is involved in the regulation of LH release. GnRH-stimulated LH release is inhibited by GnRH antagonist in a dose-dependent manner. The effects of gonadal steroids on FSH levels are less clear.

• Development and Reproduction
• /
• v.22 no.2
• /
• pp.119-132
• /
• 2018

GnRH (gonadotropin-releasing hormone) is a supreme hormone regulating reproductive activity in most animals. The sequences of amino acid and nucleic acid of GnRH reported up to now are examined from the evolutionary framework of Chordata. All identified GnRH are classified into GnRH1, GnRH2, or GnRH3. In all three forms of GnRH both N-terminal and C-terminal are conserved, which allows for effective binding to their receptors. The three amino acids in the middle of GnRH1 sequence have altered diversely from the primitive Chordata, which is indicative of the adaptation process to the ambient environment. GnRH2 and GnRH3 sequences are well conserved. There are more diverse modifications in the nucleic acids than in amino acid sequence of GnRH1. These variations can result from meiosis, mutation, or epigenetics and indicate that GnRH is the product of natural selection.

• The Korean Journal of Zoology
• /
• v.33 no.4
• /
• pp.435-445
• /
• 1990

Gonadotropin releasing horrnone (GnRH) is known to be extrahypothalamically localized with a broad range including gonad. It remains, however, unknown whether GnRH is locally synthesized in the gonad. The present srudy aims to identity expression and cellular localization of GnRH-Iike mRNA and immunoreactive GnRH in the rat gonad. GnRH radioimmunoassay and chromatographic extracts on G-50 sephadex column showed that rat gonadal extracts contained a substantial amount of immunoreactive GnRH similar to the hypothalamic and synthetic GnRH. Although a wide distribution of immunostainable GnRH-like molecule with different cell types in the rat ovary was observed, the major cell population hybridized with GnRH probe appears to be granulosa. theca cells and corpus luteum. Immunoreactive GnRH-Iike peptides were distributed m various regions of testis, including spermatogenic cells, Sertoli cells and Leydig cells. In situ hybridization revealed that positive signals of GnRH-Iike mRNA were predominandy present in Sertoli cells within some seminiferous tubules, but absent in the outside of seminiferous tubules in the testis. This study clearly demonstrated that GnRH-Iike molecule present in the rat gonad may be resulted from the local synthetic machinery of GnRH supporting the notion that this peptide may act as autocrine and/or paracrine role in intra-gonadal communication.

• Development and Reproduction
• /
• v.5 no.1
• /
• pp.81-88
• /
• 2001

Gonadotropin-releasing hormone (GnRH) has been known to play a role in the regulation of hCG secretion by human placenta. Recently, a gene encoding the second f개m of GnRH (GnRH-II) was identified in human. Herein, we demonstrate that GnRH-II is expressed in human placenta and assess GnRH-II expression by nested RT-PCR and immunohistochemistry in human placenta during the first trimester. We found that two altematively spliced transcripts of GnW-II mRNA were expressed in human placental tissues of first trimester and the shorter variant had a 21-bp deletion in GnRH-associated peptide (GAP). Immunoreactive GnRH-II was localized in both cytotrophoblastic and syncytiotrophoblastic cytoplasm. The immunostaining intensity was stronger in cytotrophoblast. Villous stromal cells also showed GnRH-II immunoreactiyiry. The results of our study report that the second isoform of GnRH (GnRH-II) is expressed in the first trimester human placenta and we suggest that GnRH-II may also play a regulatory role in maintenance of early pregnancy and hCG secretion in human placenta.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.11 no.1
• /
• pp.23-32
• /
• 1981

The purpose of this study was to assess temporomandibular joint subluxation by means of cephalometry using two lateral cephalograms from each person with in centric occlusion and wide-open mouth position, and to compare patient group with subluxation to normal control group in the measurements and correlation coefficient. The 200 cephalograms of 100 Korean adults, patient group consisted of 24 females and 26 males ranged from 17 to 63 years age and the normal control group consisted of 20 females and 30 males ranged from 18 to 56 years age, were studied and analyzed statistically. The results were as follows; 1. In the comparison of patient group vs normal control group in the measurements, statistically significant differences were found in C-C', C'-PTM, K-FH, K-PTM, Gn-Gn', C-S-C', Gn-S-Gn', Gn-K-Gn', GoGn-SN, and GoGn-Go'Gn'. K-point* of patient group was located antero - superiorly than of normal control group, and the significance level was higher in K-PTM than in K-FH. There was no statistically significant difference found in local relationship of C-point between patient group and normal control group. The values of correlation coefficient among all measurements were in 0.958≥r≥-0.760, and the highest value was in Gn-Gn' to GoGn-Go'Gn' and Gn-K-Gn' to Gn-Gn', and the lowest value was in C'-PTM to Gn-K-Gn' of normal control group. K was determined as a point of intersection by a perpendicular bisector of Gn-Gn' and a perpendicular bisector of C-C'.

• Fisheries and Aquatic Sciences
• /
• v.3 no.1
• /
• pp.37-43
• /
• 2000

We used a mammalian GnRH antagonist, $[Ac-3,4-dehydro-Pro^1,\;D-p-F-Phe^2,\;D-Trp^{3.6}]$-GnRH, to examine the details of the salmon type gonadotropin-releasing hormone (sGnRH) and GnRH agonist analog $(Des-Gly^{10}$[d-Ala^6]-ethylamide GnRH; GnRHa) functions in the control of maturational gonadotropin (GTH II) secretion, in precocious male rainbow trout, in both in vivo and in vitro experiments. In the in vivo study, plasma GTH II levels increased by sGnRH or GnRHa treatment, but the response was more rapid and stronger in the GnRHa treatment group. The increase in GTH II was significantly suppressed by the GnRH antagonist, while the antagonist had no effect on basal GTH II levels in both groups. The GnRH antagonist showed stronger suppression of GTH II levels in the sGnRH treatment fish than in the GnRHa treatment fish. In addition, plasma androgenic steroid hormones (testosterone and 11-ketotestosterone) increased by the sGnRH or GnRHa treatment. The GnRH antagonist significantly inhibited the increases in plasma androgenic steroid hormone levels stimulated by the sGnRH or GnRHa, while the antagonist had no effect on basal androgenic steroid hormone levels in both groups. In the in vitro study, treatment with sGnRH or GnRHa increased GTH II release from the cultured dispersed pituitary cells, but the response was stronger in the GnRHa treatment group. The increase in GTH II release by GnRH was suppressed by adding the GnRH antagonist, dose­dependently. On the other hand, basal release of GTH II did not decrease by the GnRH antagonist treatment in both groups. These results suggest that the GnRH antagonist, $[Ac-3,4-dehydro-Pro^1,\;D-p-F-Phe^2,\;D-Trp^{3.6}]-GnRH$, used in this study is effective in blocking the action of GnRH-induced GTH II release from the pituitary gland both in vivo and in vitro.

• Journal of Aquaculture
• /
• v.11 no.4
• /
• pp.513-519
• /
• 1998

Ovulation of maturing femal mandarin fish, Siniperca scherzeri was induced using single injection of human chorionic gonadotropin (HCG) or gonadotropin releasing hormone-analogue (GnRH-a), GnRH-a plus prostaglandin F2 (PG$F_2$) or GnRH-a plus pimozide. The response was evaluated by fertilization, embryo-formation and hatching rate after insemination. Those rates were generally higher in GnRH-a group than in HCG group. The higher hatching rat of above 89% was achived using a dosage of 5,000 IU/kg HCG plus 10 ${\mu}$g/kg GnRH-a, 10${\mu}$g/kg GnRH-a plus 500 ng/kg PGF2, and 10 ug/kg GnRH-a plus 1-5 mg/kg pimozide. Ovulation was induced in all female injected with sex-maturation hormones and stimulator, but blocked in female injected with HCG plus GnRH-a plus dopamine combination, and GnRH-a plus PGF2 plus indometacin combination. These results show that the mandarin fish in spawning period secrete a sex-mutruation assosiated hormones and gonadotropin-releasing -inhibiting factor(GRIF).