• 한국가축번식학회지
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• 제22권3호
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• pp.245-252
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• 1998

The three-dimensional structure of the Sertoli cell in the rat was investigated by scanning electron microscopy. Morphologically, seven types of Sertoli cell processes were evident : Shrot, flat and ramified processes are projected from the lateral side of the basal portion of Sertoli cell. Leaf-like processes are attached to the surface of spermatocytes and spermatids. Slender cord-like processes, flat and irregular shaped processes, sucker-like processes and club-like processes are observated in the middle and apical portion of seminiferous epithelium. The sheet-like processes rest upon more than one-thirds of the surface of each spermatogonium, spermatocyes and spermatids located in the proximity of the Sertoli cell. All Sertoli processes are originated from Sertoli cell column. Just before spermiation, the processes which are attached to the head of maturation spermatid are eliminated. Though the mechanism for elimination of residual body is not known, these observations segget that the Sertoli cell process are thought to have a reciprocity with the germ cells.

• 한국발생생물학회지:발생과생식
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• 제11권1호
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• pp.31-41
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• 2007

작은땃쥐(Crocidura shantungensis)의 정자 변태에 대한 연구를 전자현미경을 이용한 방법을 통해 이루어졌다. 정자세포의 핵과 세포질내 소기관의 형태학적 특징을 기초하여 정자 변태 전 과정을 11기(phase) 15 단계(step)로 각각 구분되었다. 골지 및 두모 단계의 정자세포가 구형인데 반해 첨체 전기에는 타원형으로 변하고, 이 시기부터 꼬리가 생성되기 시작하였고, 성숙기에는 가늘고 긴 정자 두부가 형성되었다. Step 7까지는 정자세포의 두부 방향이 내강쪽을 향하고 있는데 반해 step 8부터 step 15까지는 세정관 상피의 기저막쪽으로 향하였다. Step 12에서 정자세포는 핵과 첨체가 최대로 신장되어 나타났다. Step 13에서부터 정자세포의 핵은 납작해지고, 첨체는 납작하게 확장되면서 전체길이는 짧아지는 경향을 보였다. Step 14에 도달한 정자세포의 첨체는 정자 두부와 더불어 최종적인 모양을 취하게 되고, 핵은 쐐기모양을 하고 있으며, 염색질은 완전히 응축되고 균질화 되어졌다. 이탈기(spermiation phase)의 정자세포는 세르톨리 세포의 세포질로부터 점차적으로 떨어져 나갔으며, 이 시기에 정자세포의 첨체는 짧아지고 납작해져서 완전한 정자를 형성하였다. 이상의 결과를 종합하여 볼 때, 정자 변태과정은 정자 형성세포의 분화 단계를 분석하는데도 유용한 정보를 제공하리라 여겨진다.

• 한국발생생물학회지:발생과생식
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• 제17권4호
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• pp.353-361
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• 2013

The objective of this study was to characterize the reproductive cycle of the chameleon goby, T. trigonocephalus. Gonadal development was investigated using a histological method. Specimens were collected monthly, from April 2009 to March 2010. The gonadosomatic index (GSI) of females began to increase in April, reaching the maximum in May, and declined sharply in August. In males, the GSI began to increase in April and reaching the maximum in July. The annual reproductive cycle of T. trigonocephalus can be divided into four successive stages in females: the growing (November-March), maturing (April-May), ripe and spawning (June-July), and recovery (August-October) stages. Males passed through growing (November-March), maturing (April-June), ripe and spermiation (July-August), and recovery (September-October) stages. These results indicate the spawning season is from June to July. The relationship between fecundity (Fc) and body length (BL) was $Fc=86.1511BL^{2.6506}$. Fecundity was ranged from 3,448-9,654 eggs in a BL of 4.8-7.2 cm and it was increased as BL increased.

• 한국발생생물학회지:발생과생식
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• 제10권1호
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• pp.9-17
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• 2006

제주땃쥐(Crocidura dsinezumi)의 세정관 상피 주기와 정자세포의 형태적인 특징을 알아보기 위하여 조사하였다. 제주땃쥐의 세정관 상피 주기는 12 stages로 구분되어졌다. Ad형 정원세포는 모든 단계에서 관찰되어졌으며, In형 정원세포는 IV단계에서, B형 정원세포는 V단계와 VI단계에서 관찰되었다. 정자세포의 첨체 발달과 핵의 형태적 변화는 14 steps로 구분되어졌다. 골지, 두모, 첨체, 성숙 및 이탈단계는 각각 $1{\sim}2,\;3{\sim}6,\;7{\sim}10,\;11{\sim}14$ 및 14 step으로 구분되어 나타났다. 이러한 우리의 결과들은 제주땃쥐의 정자 변태 과정에 대한 금후의 연구에 대한 기초를 제공해준다.

• 대한수의학회지
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• 제32권3호
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• pp.295-308
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• 1992

In order to study on the Sertoli cell, we attempt have been made to measure the average number of each germ cells per Sertoli cell on the 12 stages of cycle in matured korean Jindo dog. The fine structure of Sertoli cell junctional specialization was studied with electron microscope. The results were summarized as follows; 1. The average number of various germ cells associated with Sertoli cell was 9.77 to 13. 80 through stages of cycle and the total average number was 11.62. 2. Sertoli-Sertoli cell junctional specialization was present in seminiferous epilthelium, and Sertoli-spermatid cell junctional specialization rose from stage 8 spermatid, persisted to step 13 spermatid and then disappeared. The structure of Sedoli-spermatid cell juncticnal specialization was not similar to that of Sertoli cxlls. 3. Just after spermiation, free-surface of Sertoli-spermatid cell junctional specialization was replaced by Sertoli cell cytoplasm with tubulobulbar complex at the neiglaboring region observed. 4. The Sertoli cell process was located within the cytoplasm of late stage spermatids. Some membranes of residual body and spermatid cytoplasm partly disappeared, resulting in opening of the cytoplasm of spermatid into that Sertoli cell. This fact suggested that spermatid cytoplasm was partly eliminated.

• 한국발생생물학회지:발생과생식
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• 제14권1호
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• pp.1-5
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• 2010

We investigated the androgenic effects of 11-ketotestosterone (11-KT) on gonadal sex reversal and spermatogenesis in honeycomb grouper Epinephelus merra by method of gonadal biopsy. 11-KT was injected intramuscularly at a concentration of 1 and $10{\mu}g$ body weight. The proportion of cross sectional area of the gonad occupied by each germ cell type was measured and compared pre- and post-injection group. During the sex change phase, the distribution ratio of oocytes was decreased in all fish of 11-KT treatment group while the distribution ratio of spermatocytes was increased than pre-injection group. In male phase, all fish of 11-KT treatment group shown the increased distribution ratio of spermatocytes, but the distribution ratio of spermatozoa was decreased than pre-injection group. The present results suggest that 11-KT can stimulate degeneration of oocytes, proliferation of spermatocytes and spermiation in honeycomb grouper.

• 대한의생명과학회지
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• 제13권1호
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• pp.61-69
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• 2007

The cycle of the seminiferous epithelium and the development of spermatids of Apodemus agrarius coreae were observed using a light microscope. The cycle of the seminiferous epithelium was divided into 10 stages, and developing spermatids were subdivided into 10 steps. The Golgi phases occurs the first two steps ($St_1,\;St_2$), and the cap phases had the next two consecutive steps ($St_3$ and $St_4$). The acrosomal phases consisted of steps $5{\sim}8$ ($St_5-St_8$), and the remaining two steps consisted the maturation ($St_9$) and spermiation ($St_{10}$) phases, respectively. Type Ad spetmatogonia are appeared in all stages (I-X). Type Ap spermatogonia appeared from stage I and II, In spermatogonia from stage III, IV and V, and B spermatogonia from stages VI. The leptotene spermatocytes appeared from stage VII, zygotene from stages I, II, VIII, IX and X, pachytene from stage III to VIII, diplotene in stage IX, and meiotic figures and secondary spermatocytes in stage X. These data are considered in relation to interspecific differences in sperm morphology.

• Applied Microscopy
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• 제31권3호
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• pp.257-266
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• 2001

황소개구리의 정자변태과정과 정자형성단계 중에 글리코겐이 정자 성숙에 미치는 역할을 알아보기 위하여 관찰한 결과는 다음과 같았다. 정자변태과정은 핵과 세포질 소기관의 형태적 특징을 토대로 하여 3단계로 나눌 수 있었다. 특히, 정자형성단계 중에서 글리코겐은 정원세포부터 정모세포발생 단계까지는 관찰되지 많았지만, 정자변태단계인 초기 정자세포부터 성숙기까지는 정자세포의 핵과 첨체 및 세포질 내에 존재하고 있었고, 성숙한 정자의 중편부에도 위치하고 있었다. 이러한 사실은 글리코겐이 정자 성숙에 중요한 역할을 수행할 뿐만 아니라 정자의 파동운동에 에너지원으로서 중요한 역할을 할 것으로 사료된다.

• Applied Microscopy
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• 제31권2호
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• pp.143-156
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• 2001

본 연구는 황소개구리의 정소내 생식세포분화 단계와 정자변태과정중의 정자의 형태적 특징을 알아보기 위하여 조사한 결과 다음과 같은 결론을 얻었다. 황소개구리의 정자형성과정 중 생식세포는 제1정원세포, 제2정원세포, 제1정모세포, 제2정모세포 및 정자세포로 구성되어져 있으며, 이들 생식세포의 분화단계는 세포의 형태적 특정을 기초로 하여 총 8단계로 구분되어졌다. 제1정원세포를 제외한 정모세포발생 단계에서부터 이탈 전까지의 정자세포는 정낭내에 존재하고 있었다. 정자변태과정은 3단계로 구분되어졌다. 성숙기의 정자의 첨체는 낭상이고, 두부의 모양은 양끝이 가는 원통형이었으며, 꼬리는 단지 축사로만 구성되어져 있었다.

• 한국발생생물학회지:발생과생식
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• 제25권3호
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• pp.157-171
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• 2021

To determine whether the reproductive processes of sea bass, Lateolabrax japonicus, proceed normally after transportation from an outdoor net-cage into indoor tanks, we examined changes in the gonadosomatic index (GSI), histological gonadal tissue, and plasma levels of sex hormones (testosterone and estradiol-17ß) during their annual reproductive cycle. We also measured maturation and spawning across two sea water salinity levels (full and low salinity). Fecundity was estimated by the relationship between egg number and body size in female sea bass. Monthly changes in the GSI, histological gonadal tissues, and oocyte size showed both male and female sea bass reach final maturation in January and February, respectively, indicating that the spermiation of males occurs earlier than the spawning of females. The histological results indicated that the sea bass is a multiple spawner, similar to many marine teleosts, exhibiting group-synchronous oocyte development. Female maturation and spawning were enhanced in lower salinity seawater (29.6-31.0 psu) compared to that of normal salinity (34.5-35.1 psu). These results confirm that sea bass reproduction can occur successfully in captivity and imply that fertilized eggs can be collected from February to March. Additionally, our results show that lower salinity enhances oocyte maturation and spawning of female sea bass.