• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.63-63
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• 2003

In an effort to uncover the spermatogenic impairment by the polychlorinated biphenyls (PCBs), the expression of tight junctions (TJs) genes important for the formation of the blood testis barrier (BTB) were examined following the 3,3',4,4',5-pentachloro biphenyl (PCB126) treatment in cultured neonatal testis in mice. At 4 days (D4) after 10 and 100 nM PCB126 treatment the expression of claudin-11 was significantly increased when compared with vehicle control. In contrast no difference in occludin and claudin-1 expression was found among the experimental group. On D8, 100 nM PCB126 significantly increased the expression of claudin-11 but not occludin and claudin-1. 1 uM PCB126 treatment significantly decreased expressions of occludin and ciaudin -1, suggesting the general toxic effect on the Sertoli cell. Because PCB126 does not alter the proliferative activity of spermatogenic cells and Sertoli cells in neonatal testis, it is likely that increase in the expression of claudin-11 by low dose of PCB126 may attribute to the alteration of the Sertoli cells differentiation in testis. It also emphasized that PCB126 might have differentially affected the transcription of TJ genes in Sertoli cells. In conclusion, this result suggests that the structure of TJ may be targeted by PCB126 in neonatal testis in mice and that co-PCB is potentially harmful to spermatogenesis by alteration of the development of BTB.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2003년도 학술발표대회 발표논문초록집
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• pp.96-96
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• 2003

Nek2 (NIMA-related protein) is a mammalian cell cycle-regulated kinase that involves in chromosome condensation and centrosome regulation and NuMA (nuclear mitotic apparatus protein) is involved in spindle assembly during a cell cycle. The cellular distribution and organization of the centrosomal components is completely unknown during fertilization and embryonic development. We examined distribution of two well-known centrosomal proteins, Nek2 and NuMA in mouse gametes and embryos to get an insight in the reorganization of centrosomal proteins during germ cell development and early fertilization. Spermatogenic cells, gametes, and embryos were analyzed with anti-Nek2 or -NuMA antibodies by immunological assay, RT-PCR, and overexpression through gene transfection. Mitotically or meiotically active spermatogenic cells were intensively stained with these antibodies in both centrosomes and cytoplasm, whereas the oocytes showed different staining patterns depending on the meiotic stages. During maturation, GV, GVBD, and MI stage were clearly stained with NuMA antibody in the nucleus or cytoplasm at MII. Also, Nek2 was detectable in cytoplasm as scattered spots or chromosome associated at MII. In early developmental embryo, NuMA was detected in nucleus of each blastomere, while Nek2 was detected in cytoplasm. In contrast to previously reported results, Nek2 and NuMA were detected in both decondensing head, and the centriole of demembranated and decondensed sperm or whole body of trypsin-treated sperm for Nek2. During meiotic progress in oocytes, transcripts levels were the highest in MI stage and then downregulated in MII. Also, it shows dramatically change in early developmental embryos, firstly, it was increased until 4 cell stage and reduced in 8 cell stage, and finally, transcript levels were upregulated until blastoscyst. This finding suggests that cnetrosomal component may play an important role in reorganizing of functional centrosome during fertilization process and subsequent development.

• Applied Microscopy
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• 제31권3호
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• pp.245-256
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• 2001

본 연구는 붉은머리오목눈이(Paradoxornis webbiana)의 정자변태 과정을 알아보기 위하여 전자현미경으로 세포분화 단계에 따른 세포구조물의 특징을 기초로 하여 관찰한 결과 정자변태의 전과정을 10단계로 나타내었다. 염색질의 변화는 골지기에서 균질한 섬유상의 형태가 두모기에서는 서서히 응축하여 첨체기에 막대상으로 응축되고 성숙기에 이르러 더욱 응축되고, 균질화되어 완전한 핵을 형성하였다. 꼬리의 형성시기는 초기 골지단계에서 시작하여 성숙후기에 완료되었다. 축사는 9+2구조이며, 미토콘드리아 다발은 2개가 1조를 이루어 축사를 중심으로 $15^{\circ}$ 각도로 규칙적으로 배열되어 있었다. 그리고 microtubules들이 미토콘드리아 외막을 둘러싸고 있었다 정자의 파동막의 형태는 S자형으로 정자원형질막을 둘러싸고 있었다.

• 대한수의학회지
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• 제34권4호
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• pp.665-678
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• 1994

This study was undertaken to investigate histological changes according to the radiosensitivity in the spermatogenic cells in Korean native pheasants. During spermatogenetic period, testes wete collected from male adult Korean native pheasant and they were used as experimental and control birds. The experimental group was divided into a single-dose whole body irradiation group(400, 600, 800 and 1000 rads) and a split-dose whole body irradiation groups(400/2, 600/2, 800/2 and 1000/2 rads). A Henseky's $^{60}Co$ ${\gamma}$-radiotherapy machine was used for this experiment and the dose rate of $^{60}Co$ ${\gamma}$-ray was 104 rads/min. The experimental birds were sacrificed at 24 and 72 hrs after irradiation and the control pheasants were sacrificed at the same time. General histological changes of seminiferous epithelial cells were observed by hematoxylin-eosin stain with light microscope. The results obtained are summarized as follows ; 1. In the single-dose and the split-dose irradiation groups, the average diameter of the seminiferous tubule was decreased compared with control group. 2. Seminiferous epithelial cells were more severely damaged after 72 hrs than after 24 hrs of single-dose irradiation of 400, 600 and 800 rads but the difference of cell injury was almost not observable with the elapsed time in the group of the single-dose irradiation of 1000 rads. 3. The damage of spermatogenic cells were more severe after 24 hrs than after 72 hrs of the split-dose irradiation of 400 rads but the split-dose irradiation of 600, 800 and 1000 rads were more severe after 72 hrs than after 24 hrs.

• BMB Reports
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• 제41권9호
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• pp.664-669
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• 2008

Znf230, the mouse homologue of the human spermatogenesis-related gene, ZNF230, has been cloned by rapid amplification of cDNA ends (RACE). This gene is expressed predominantly in testis, but its expression in different testicular cells and spermatogenic stages has not been previously analyzed in detail. In the present study, the cellular localization of the Znf230 protein in mouse testis and epididymal spermatozoa was determined by RT-PCR, immunoblotting, immunohistochemistry and immunofluorescence. It is primarily expressed in the nuclei of spermatogonia and subsequently in the acrosome system and the entire tail of developing spermatids and spermatozoa. The results indicate that Znf230 may play an important role in mouse spermatogenesis, including spermatogenic cell proliferation and sperm maturation, as well as motility and fertilization.

• 대한수의학회지
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• 제34권1호
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• pp.9-18
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• 1994

The morphological changes of Sertoli cells of the Korean native pheasant were studied in the active and inactive spermatogenic phases. Twenty-four male of the pheasants were studied in the active (April~June) and inactive(August~March) phase. These data are useful in studying the male genital organs of the Korean native pheasant. Light microscopic morphological changes of the Sertoli cells were studied on paraffin-embedded sections stained with hematoxylin-eosin stain. Ultrastructural changes of Sertoli cells were investigated of ultrathin section using electron microscope. Results are summarized as follows: During the active phase, the average diameter of seminiferous tubule was $245.33{\pm}29.93{\mu}m$ and was largely decreased by $94.50{\pm}14.10{\mu}m$, and the thickness of interstitial tissue was comparatively increased during the inactive phase. During the active phase, in the cytoplasmic process of Sertoli cell and lipid droplets appeared disperse. Well-developed smooth Endoplasmic Reticulum and microtuble were observed in the cytoplasmic process. The nuclei of Sertoli cells were adjacent to the basement membrane. The size of nuclei was reduced and nuclei of Sertoli cells were densely packed within the tubule. Few collagen fibers, fibroblast and various sizes of lipid droplets were observed in the interstitial cell of the seminiferous tubule.

• Applied Microscopy
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• 제41권3호
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• pp.179-188
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• 2011

성숙한 2년산 미꾸라지(Misgurnus mizolepis) 친어로부터 3배체를 유도하여 이들 3배체의 정자형성과정에 따른 생식세포의 미세구조를 조사하여 2배체 숫컷과 비교하였다. 3배체 숫컷의 정자형성과정과 세포학적 미세구조는 2배체와 유사한 특징을 나타내었다. 정자변태과정이 일어나는 시기에 3배체의 정소 소엽내 Sertoli cell은 세포질 내 다수의 미토콘드리아 로제트, 소포체, 그리고 소량의 지방적 등을 함유하는 등 높은 활성을 나타내었다. 3배체 숫컷의 정소에서 일부 성숙한 정자들이 식별되었다. 변태를 완료한 3배체의 정자는 두부, 중편 그리고 미부축사로 구성되어 2배체 정자와 같은 anacrosomal aquasperm으로 나타났으나 생식세포 발달단계별 핵의 크기가 2배체보다 크고, 정자를 구성하는 cytoplasmic cannal의 직경이 크며 cytoplasmic collar의길이가 길고 미부축사의 직경이 굵고 두 개 이상의 미부축사를 가지는 등 비정상적인 구조를 나타내었다.

• Fisheries and Aquatic Sciences
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• 제21권11호
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• pp.34.1-34.13
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• 2018

Sexual maturity ($L_{50}$), the length at which 50% of fish in a size class are mature, is a key aspect of domestication of new fish species because it guides the procedure for identification of appropriate broodstock size for artificial spawning. In this study, the $L_{50}$ was determined for 1083 Barbus altianalis samples obtained from Lake Edward and the Upper Victoria Nile. Gonads of freshly killed samples were examined macroscopically and verified with standard histological procedures for the maturation stages that were used to determine $L_{50}$. Oocytes and spermatogenic cell sizes were compared for fish obtained from both water bodies. Results indicated that there were no variations in macro gonad features observed for fish from Lake Edward and Upper Victoria Nile. Similarly, there were no significant differences in oocyte sizes (P > 0.05) between the two populations but significant differences in spermatogenic cell sizes were noted (P < 0.05) except for spermatozoa (P > 0.05). This however did not suggest peculiar differences between the two populations for staging the gonads. Consequently, no staging variations were suggested for both populations in determination of $L_{50}$. Sexual maturity was found in the same class size of fork length (FL) 20-24.9 cm and 35-39.9 cm for males and females from both water bodies, respectively. At this FL, however, males were too small, and for good selection of vigor broodstocks for spawning and conservation purposes, they are better picked from class size of 30-34.9 cm FL and above. These findings were crucial for integration of appropriate breeding size in spawning protocol by farmers and fisheries scientists conserving wild B. altianalis populations.

• 한국발생생물학회지:발생과생식
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• 제1권2호
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• pp.125-132
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• 1997

To investigate the cadmium (Cd) toxicity on the testis, male rats were treated with 1, 2, 4 and 8 mg/kg of Cd by IP. According to histochemical studies, Cd-treated testis tissue showed death of spermatozoa, death of Sertoli cells, death of all the spermatogenic cells, and finally disappearance of basal lamina of seminiferous tubules with increasing doses, and showed decreased ground substances and Leydig cells, increased inflammatory cells and fibroblasts, and fibroblasts, and finally disappearance of ground substances and all the cells except fibroblasts within interstitial tissues with increasing doses. According to biochemical studies, two kinds of proteins, 25 and 45 kDa, were dramatically disappeared from the total protein of rat testis treated with Cd comparing to normal testis. The result of electrophoresis of total protein suggests that actin (45 kDa), presumed on its mmolecular weight and amount, in the testis-cells is the primary target of Cd poisoning. Although its exact mechanism is not clear, the disappearance of two proteins when testis is exposed to Cd should give some clues to understnad the mechanism of necrosis of testis tissue crumbling by heavy metal pollutant such as Cd.

• 한국발생생물학회지:발생과생식
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• 제17권2호
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• pp.87-97
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• 2013

The seminiferous epithelium cycle and developmental stages of spermatids in Clethrionomys rufocanus were observed under a light microscope. The seminiferous epithelium cycle was divided into 8 stages. Type Ad spermatogonia appeared through all stages. Type Ap, In, and B spermatogonia appeared in stages I, II, III, and IV. In the first meiosis prophase, the leptotene spermatocytes appeared from stage V, the zygotene spermatocytes in stages I, VI, VII, VIII, the pachytene spermatocytes from stages II to VI, the diplotene spermatocytes in stage VII. The meiotic figures and interkinesis spermatocytes were observed in stage VIII. Developing spermatids were subdivided into 10 steps, based on the morphological characteristics such as the acrosome formation changes in spermatozoa, nucleus, cytoplasm, and spermiation changes. The C. rufocanus spermatocytogenesis and spermiogenesis results displayed similar results with Apodemus agrarius coreae and A. speciosus peninsulae. Considering all the results, the spermatogenesis may be useful information to analyze the differentiation of spermatogenic cells and the breeding season.