• 한국양식학회지
• /
• 제19권4호
• /
• pp.267-274
• /
• 2006

자연산(silver 및 yellow) 뱀장어의 인위적인 성성숙 과정중에 체중 및 혈중 성호르몬 농도를 조사하기 위해 연어 뇌하수체 추출물(SPE; 20 mg pituitary powder/fish)를 Freund's incomplete adjuvant로 water-in oil (W/O) 형태로 유화시켜 매주 복강에 주사하였다. Eel's Ringer액만으로 유화시켜 주사한 대조구(silver 및 yellow) 뱀장어의 경우, 체중은 서서히 감소하는 경향을 나타내었으며, 혈중 성호르몬(testosterone; T, $estradiol-17{\beta};\;E_2$ 및 $17{\alpha},20{\beta}-dihydroxyprogesterone$; DHP)의 농도도 실험기간 동안 거의 변화없이 서서히 감소하는 경향을 나타냈었지만 유의적인 변화는 없었다. 한편, 매주 SPE로 주사한 silver 뱀장어는 투여 6주후부터 급격한 체중변화가 일어났으며, 대부분 개체의 난모세포는 핵이동기로 구성되어져 있었다. 또한 혈중 T와 $E_2$ 농도의 두드러진 증가는 투여 6주후부터 관찰되어 졌다. 매주 SPE로 주사한 yellow 뱀장어의 경우, 대부분 개체는 투여 5주까지 체중 변화가 완만하게 나타났으며 그 이후 급속히 증가하였다. 이들 개체의 대부분은 실험종료시에도 제3 난황구기의 난모세포들로 구성되어져 있었다. 특히 실험 기간중 혈중 T와 $E_2$ 농도는 개체별로 다양하게 나타났으며, 유의한 차이는 제각기 투여 8주째와 투여 6주 후 부터 두드러지게 증가하였다. 그러나 매주 SPE로 주사한 자연산 뱀장어(silver 및 yellow)의 혈중 DHP 농도는 실험 기간동안 불검출 혹은 매우 낮은 농도로 유지하였으며, 유의적인 변화는 관찰되지 않았다. 본 연구의 결과, sliver 뱀장어에 있어서 SPE를 W/O 형태로 유화시켜 반복 투여함으로써 체중 및 혈중 성호르몬(T와 $E_2$)의 급격한 증가 및 최종성숙을 유도하는데 효과적이었다.

• 한국발생생물학회지:발생과생식
• /
• 제11권1호
• /
• pp.1-11
• /
• 2007

착상기 이전 자궁에서 특이적 자궁내막 준비가 진행되어야 하는데, 이는 자궁 내막의 점진적 분화로 배아의 착상과 성공적 임신에 절대적으로 필요하다. 배아 발생 동안에 관찰되는 조직의 재구성은 세포외 기질을 포함한 다양한 요인에 의해 조절된다. 임신 동안에 관찰되는 극적인 변화로는 배아의 이동, 탈락막 반응, 태반의 분화를 그 예로 들 수 있다. 배아와 자궁간의 성공적 착상을 위한 변화들은 배아와 자궁의 착상을 위한 능력 갖출 수 있도록 한다. 이러한 변화과정 중에, 콜라겐이 주성분인 세포외 기질의 극적인 변화가 진행된다. 이러한 변화는 매우 복잡하여 그 기작을 밝히는 것은 쉽지 않으나, 최근 들어 PCR-select cDNA subtraction 방법, microarry 방법 등 대단위 유전자 동정 방법들을 이용하여 많은 후보 유전자가 동정되었다. 스테로이드 호르몬은 임신과 임신 유지에 중요한 역할을 수행하며, 세포외 기질의 재구성을 엄격하게 성스테로이드 호르몬에 의한 유전자 네트워크를 통하여 조절한다. 자궁의 세포외 기질의 병리적 조절이 당뇨병 등에서 보고되고 있다. 세포외 기질의 재구성은 착상과 태아와 자궁의 발달을 이해하는 데 중요하고, 또한 생식과 관련된 질병을 극복하는 데 중요하다. 비록 세포외 기질의 구성성분이 매우 다양하고 복잡하여 논의할 것이 무척 많으나, 본 종설에서는 착상기를 전후한 시기에 콜라겐의 변화를 중심으로 논하였다.

• Toxicological Research
• /
• 제33권1호
• /
• pp.49-54
• /
• 2017

Vitamin D3 is a fat-soluble secosteroid responsible for enhancing intestinal absorption of calcium, iron, and other materials. Vitamin D3 deficiency, therefore, can cause health problems such as metabolic diseases, and bone disorder. Female sex hormones including estrogen and progesterone are biosynthesized mainly in the granulosa cells of ovary. In this study, we isolated granulosa cells from porcine ovary and cultured for the experiments. In order to examine the effect of vitamin D3 on the ovarian granulosa cells, the mRNA and protein levels of genes were analyzed by real-time PCR and Western blot assay. The production of estrogen from the granulosa cells was also measured by the ELISA assay. Genes associated with follicle growth were not significantly altered by vitamin D3. However, it increases expression of genes involved in the estrogen-biosynthesis. Further, estrogen concentrations in porcine granulosa cell-cultured media increased in response to vitamin D3. These results showed that vitamin D3 is a powerful regulator of sex steroid hormone production in porcine granulosa cells, suggesting that vitamin D deficiency may result in inappropriate sexual development of industrial animals and eventually economic loss.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제35권6호
• /
• pp.403-410
• /
• 2009

Those composing temporomandibular joint (TMJ) complex such as the temporal bone, the disc and the mandibular condyle perform their own functions with organic relation. The retrodiscal tissue is the main area of pain induction and contributes to compositional change of synovial fluid. If displacement of the disc lasts long time, not only adaptive changes, but also destructive or degenerative changes may happen. It was reported that these changes and symptoms appear mostly to female rather than male and especially, in the case of patients suffering from TMJ disorder, a large quantity of female sex hormone is found in the joint synovium. And that may play a role in bone resorption and inflammation. Also, the frequency and the intensity of pain perception for female is reported to be much more than for male. In this study, we investigated the expression extents of estrogen receptors (ER) and progesteron receptors (PR) in retrodiscal tissue with immunohistochemistry among the patients received TMJ surgery and compared with MRI findings and surgical findings. We report the relations between the expression of ER in retrodiscal tissue and the pathological change in TMJ, such as inflammation, internal derangement and osteoarthritis.

• 한국발생생물학회지:발생과생식
• /
• 제1권2호
• /
• pp.189-202
• /
• 1997

The hypothalamic peptide GnRH plays a central role in the regulation of the mammalian reproductive axis. Recent studies suggested that GnRH stimulates or inhibits the ovarian steroidogenesis and gametogenesis directly. Our previous report indicated that GnRH gene is expressed in adult rat ovary as well as in hypothalamus and that the expressed GnRH may induce the follicular atresia and apoptosis of ovarian granulosa cells in rat. Therfore, we studied whether GnRH gene is expressed in the mouse fetal ovary, when the germ cells are degenerating by apoptosis during gonad diffeerentiation. Mouse fetal gonads were obtained on the 12, 15,18 and 20th day of gestation from the mother mice superovulated (10 IU PMSG and 10 IU hCG) and mated. The morphological changes of fetal ovaries were examined histochemically by hematoxylin-eosin staining. The fetal sex was confirmed by PCR methods for sexing. RT-PCR methods were used to examine the expression of GnRH gene and the sex steroid hormones were determined by conventional radioimmunoassays. The levels of estradiol (E) and progesterone (P) were increaseduntil 18th day of gestation and then E was decreased just before parturition. The morphological changes of fetal gonadal tissue sections showed the ovarian development and coincided with the result of PCR analysis for sexing using ovary- or testis- specific oligonucleotide primers. Immunoreactive GnRH in placenta was decreased gradually until the end of gestation but fetal brain and ovarian GnRH were increased. The level of GnRH gene expression was increased during fetal ovarian development from 12 till 18th day and decreased suddenly on 20th day just before birth. From these results, it is suggested that ovarian GnRh may play a regulatory role on the germ cell differentiation of fetal ovary.

• 한국양식학회지
• /
• 제20권3호
• /
• pp.154-159
• /
• 2007

Manchurian trout (Brachymystax lenok) is an endangered fish species in East Asia including the Korean peninsula. To establish a method for artificial propagation and to improve our understanding of the reproduction in the species, we have produced recombinant gonadotropins, follicle-stimulating hormone (r-mtFSH) and luteinizing hormone (r-mtLH), which may play central roles in reproductive activities. In the present study, the biological activities of the recombinant hormones were analyzed by gonadosomatic index (GSI), ovarian follicle diameter, and sex steroid levels in mature rainbow trout (Oncorhynchus mykiss). In the 6th day post-injection, FSH-injected fish were slightly decreased in the GSI value, although there were no significant differences among those of control, r-mtFSH, and r-mtLH treatments. Injection of the r-mtFSH increased follicle diameters significantly as compared with those of control- and r-mtLH-injected fish. The plasma steroid levels showed wide differences in the groups at 1, 3, or 6th day post-injection. Despite the variable steroid levels, three individuals receiving either r-mtFSH or r-mtLH showed a great increase in a maturation-inducing steroid, $17{\alpha},20{beta}$-dihydroxy-4-pregnen-3-one, at 3 and 6 days. Taken together, these results suggest that biological efficacies of the recombinant FSH and LH should be further studied in the Manchurian trout.

• 한국환경보건학회지
• /
• 제41권3호
• /
• pp.147-162
• /
• 2015

Objectives: The objective of this review was to summarize the primary role of three representative endocrine axes in aquatic vertebrates and discuss the effects on endocrine systems and their interactions in teleost fish after exposure to environmental contaminants. Methods: We summarized individual traits and mechanisms for hormonal and transcriptional interactions between the hypothalamic-pituitary-gonad (HPG), hypothalamic-pituitary-thyroid (HPT), and hypothalamic-pituitary-adrenal (HPA) axes in fish. We also provided a brief discussion on the effects of nonylphenol-induced toxicity on endocrine systems and their interactions in fish as a demonstration of holistic explanation. Results: Currently-available data showed that thyroid dysfunction is associated with reproductive toxicity due to changes in steroidogenic gene expressions and sex hormone levels as well as gonad glands in fish. As an example, we demonstrated that exposure to nonylphenol could induce estrogenicity in male fish by decreasing thyroid hormones, which contributes to increased aromatase expression. Although the mechanisms are complicated and involved in multiple ways, a number of studies have shown that sex steroids influence the HPT axis or the HPA axis in fish, indicating bi-directional crosstalk. Critically missing is information on the primary target or toxicity mechanisms of environmental contaminants among the three endocrine axes, so further studies are needed to explore those possibilities. Conclusions: This review highlights the interactions between the HPG, HPT, and HPA axes in fish in order to better understand how these endocrine systems could interact with each other in situations of exposure to endocrine disrupting chemicals.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제17권3호
• /
• pp.147-154
• /
• 2014

Purpose: Gender differences in paediatric patients with inflammatory bowel disease (IBD) are frequently reported as a secondary outcome and the results are divergent. To assess gender differences by analysing data collected within the Swiss IBD cohort study database since 2008, related to children with IBD, using the Montreal classification for a systematic approach. Methods: Data on gender, age, anthropometrics, disease location at diagnosis, disease behaviour, and therapy of 196 patients, 105 with Crohn's disease (CD) and 91 with ulcerative or indeterminate colitis (UC/IC) were retrieved and analysed. Results: The crude gender ratio (male : female) of patients with CD diagnosed at <10 years of age was 2.57, the adjusted ratio was 2.42, and in patients with UC/IC it was 0.68 and 0.64 respectively. The non-adjusted gender ratio of patients diagnosed at ${\geq}10$ years was 1.58 for CD and 0.88 for UC/IC. Boys with UC/IC diagnosed <10 years of age had a longer diagnostic delay, and in girls diagnosed with UC/IC >10 years a more important use of azathioprine was observed. No other gender difference was found after analysis of age, disease location and behaviour at diagnosis, duration of disease, familial occurrence of IBD, prevalence of extra-intestinal manifestations, complications, and requirement for surgery. Conclusion: CD in children <10 years affects predominantly boys with a sex ratio of 2.57; the impact of sex-hormones on the development of CD in pre-pubertal male patients should be investigated.

• 한국수산과학회지
• /
• 제39권5호
• /
• pp.391-397
• /
• 2006

This study correlated changes in estradiol-l7$\beta$ ($E_2$), testosterone (T), 17$\alpha$,20-dihydroxy-4-pregnen-3-one (DHP), and vitellogenin (VTG) levels with changes in the gonadosomatic index (GSI) and ovarian histology during the annual reproductive cycle of the wild marbled sole, Limanda yokohamae. Synchronous oocyte development occurs in this fish. Ovary maturity was classified into four periods, based on histological observations: the spawning (December to February), post-spawning (February to April), recovery (May to August), and vitellogenic (September to November) periods. Seasonal changes in the GSI were inversely correlated with water temperatures and reflected the degree of ovarian maturity. Plasma VTG levels were correlated with changes in the GSI, which increased from September to a peak in January, and levels remained comparatively high until February. Estradiol-17$\beta$ was at baseline levels (<0.11 ng/mL) during the spring and summer, and peaked rapidly (1.55$\pm$0.445 ng/mL) from October to January. Plasma T and DHP levels had a similar profile; they rose markedly during the spawning period and remained low (or were not detectable) from spring through autumn. These data indicate that changes in plsama steroid hormones and VTG levels are correlated with the annual ovarian activity of the marbled sole. Based on these results and published reports, it appears that in this species DHP is the most important maturation-inducing steroid and that T is also related to final maturation.

• Ocean and Polar Research
• /
• 제38권1호
• /
• pp.81-88
• /
• 2016

In many fish species, including Nile tilapia (Oreochromis niloticus), gonadal development occurs at the expense of stored energy and nutrients. Therefore, reproductive systems are inhibited by limited food supply. It has been well established that reproductive function is highly sensitive to both metabolic status and energy balance. Nothing is known about the possible mediated connection between energy balance and reproduction. Kisspeptin, a neuropeptide product of the Kiss gene has emerged as an essential gatekeeper of reproduction and may be possibly be linked to energy balance and reproduction in non-mammalians. Thus, in this study, the effect of fasting (10 days) on the expression of kisspeptin and the gonadotropin-releasing hormone (GnRH) gene were assessed in Nile tilapia (male and female) using qRT-PCR. In addition, plasma levels of estradiol-$17{\beta}$ ($E_2$) and 11-ketotestosterone (11-KT) in adult tilapia were measured by ELISA. In male tilapia, fasting reduced Kiss2 and GnRH I mRNA expression in the brain and 11-KT level in comparison with the fed tilapia (p < 0.05). In females, however, there were no significant differences in GnRH I mRNA expression and $E_2$ between fish subjected to fasting and those fed (p > 0.05). These data indicate the impact of nutritional states on kisspeptin as a potential regulatory mechanism for the control of reproduction in male Nile tilapia.