• 한국가금학회지
• /
• 제23권1호
• /
• pp.1-7
• /
• 1996

본 연구는 일본산 메추리(Japanese quail)에 대해 다배체의 유기를 목적으로 성숙된 수컷에 일정량의 분열 억제제를 투여하여, 정자 형성과정 중 이에 미치는 영향과 배수성 정자 세포들의 유기 양상을 분석하고자 하였다. 시험은 25∼30주령된 메추리 수컷 50수를 공시하고 체중 100 g당 37 g의 colcemid를 3일간 연속복강 주사한 후 5일째, 10일째, I5일째 및 20일째 정소세포들의 감수분열 양상을 살펴보고자 각 정원세포들의 中期像, 제 1정모세포들의 중기상 및 제 2정모세포들의 중기상의 양상들을 분석하였다. 분석 결과 colcemid 처리에 따른 전체 정소 세포 중 9.4%％가 배수성 세포로 유기된 반면, colcemid를 투여하지 않은 대조구에서는 2.3％만이 배수성 정소 세포를 나타내어 colcemid 처리에 따른 배수성 정자의 유기 가능성을 시사하고 있다. Colcemid 처리 후 10일째 11.7％의 다배수성 정자세포 유기율을 나타내어 처리 중 가장 높은 유기율을 보인 반면, 정원세포로 성숙되기 5일 이전의 대부분 원시 정세포들은 colcemid의 처리 영향을 거의 받지 않는 것으로 나타났다. 따라서 가금류에 있어 분열 억제제 투여에 의한 정자 세포의 배수성 유기는 정자 형성과정 개시 최소 10∼15일 이전의 원시 정세포에 주로 이의 영향이 미치는 것으로 나타나고, 제1, 2감수 분열 중의 방추사의 억제로 인한 배수성의 유기보다는 정원세포들의 유사분열 중 방추사 형성의 억제에 보다 민감하게 작용하여 배수성 정모세포를 형성하는 것으로 생각된다.

• Applied Microscopy
• /
• 제26권3호
• /
• pp.267-275
• /
• 1996

The internal ultrastructural changes of germ cells and external morphology of spermatozoon during the spermatogenesis in the rockfish, Sebastes inermis were studied using transmission and scanning electron microscope. The testis is seminiferous tubule type in internal structure. Seminiferous tubule consist of many cyst which contain numerous germ cells in same developmental stage. Spermatogonium contained a large nucleus with single nucleolus in interphase. Primary spermatocyte identified by the presence of synaptonemal complex in nucleus and the contained a number of mitochondria, endoplasmic reticula and Golgi bodies in cytoplasm. The nucleoplasm of secondary spermatocyte was more concentrated than that of the previous phase. Spermatids were more condensed in nucleus and cytoplasm, and show the long-spherical shape. In the cytoplasm of spermatid mitochondria located to lower portion of the nucleus and Golgi bodies located to upper portion, but proacrosomal granule is not appeared. The spermatozoon consist of the head and tail. No acrosome could be found in the head. The cytoplasmic collar of posterior part in sperm head contained mitochondria which surrounded axial filament. The well developed axonemal lateral fins were identified in sperm flagellum, and the axial filament of the flagellum consist of nine pairs of peripheral microtubules and one pair of central microtubules.

• Clinical and Experimental Reproductive Medicine
• /
• 제26권1호
• /
• pp.103-109
• /
• 1999

Objective: Heat shock protein 70-2 (Hsp70-2) gene knockout mice are found to have premeiotic arrest at the primary spermatocyte stage with a complete absence of spermatids and spermatozoa. This observation led to the hypothesis that hspA2 may be disrupted in human testes with abnormal spermatogenesis. To test this hypothesis, we studied the mRNA expression of hspA2 in infertile men with azoospermia. Design: The mRNA expression were analyzed by competitive RT-PCR among testes with normal spermatogenesis, pachytene spermatocyte arrest, and sertoli-cell only syndrome. Materials and methods: Testicular biopsy was performed in men with azoospermia (n=15). Specimens were subdivided into three groups: (group 1) normal spermatogenesis (n=5), (group 2) spermatocyte arrest (n=5), (group 3) Sertoli-cell only syndrome (n=5). Total RNA was extracted by Trizol reagent. Total extracted RNA was reverse transcribed into cDNA and amplified by PCR using specific primers for hspA2 target cDNAs. A competitive cDNA fragment was constructed by deleting a defined fragment from the target cDNA sequence, and then coamplified with the target cDNA for competitive PCR. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was used as an internal control. Results: On Competitive RT-PCR analyses for hspA2 mRNA, significant amount of hspA2 expression was observed in group 1, whereas a constitutively low level of hspA2 was expressed in groups 2 and 3. Conclusion(s): The study demonstrates that the hspA2 gene expression is down-regulated in human testes with abnormal spermatogenesis, which in turn suggests that hspA2 gene may play a specific role during meiosis in human testes.

• 대한생식의학회:학술대회논문집
• /
• 대한불임학회 2006년도 The 5th Biannual Meeting of Pacific Rim Society for Fertility and Sterility
• /
• pp.168.1-168.1
• /
• 2006

• 한국가금학회지
• /
• 제27권1호
• /
• pp.63-71
• /
• 2000

The testis is an extremely heterogeneous organ, containing numerous compartments types. Morphometric studies were performed of 3 avian species (pigeon, pheasant and chicken) to determine volume density absolute volume, numerical density, total number of serminiferous tubule components, and sperm production, especially those related to the Sertoli cell, and to make comparisons among the species. Volume density of seminiferous tubule components per testis was determined by point counting method. Testis volume and sperm production were measured by routine techniques. Numerical density (the number of cells per unit volume of testis) of seminiferous tubule components per testis was determined by morphometry (Floderus method). The volume density of seminiferous tubules per testis was 91.58, 92.18 and 94.21% in pigeon, pheasant, and chicken, respectively. The volume density of spermatogonium, spermatocyte, spermatid, spermatozoon, and Sertoli cell did not produce significant changes in the three species. The absolute volume of spermatogonium, spermatocyte, spermatid, and Sertoli cell showed significant changes in the three species (p<0.05). The average volume of Sertoli cell ranged from 758.34(pheasant) to 1,212.9 ㎛$^3$(chicken) and was not significantoy different in the three species(p>0.05). The number of Sertoli cells per testis showed significant differences in the three species : 34.52 $\times$10(sup)6, 186.82$\times$10(sup)6, 810.62$\times$10(sup)6 in pigeon, pheasant, and chicken, respectively(p<0.05). The sperm production was significantly different in the three species : 3,018$\times$10(sup)6, 993.9$\times$10(sup)6, and 8.9$\times$10(sup)6 in chicken, pheasant, and pigeon, respectively(p<0.05). These results suggest that number of Sertoli cells may be more important than Sertoli cell size in explaining the difference in sperm production among the three species.

• 대한수의학회지
• /
• 제31권4호
• /
• pp.355-365
• /
• 1991

This study was conducted in order to observe the changes in cellular association of seminiferous tubules from 16 to 24 weeks of age and to obtain the cycle and relative duration of the seminiferous epithelia from 28 to 44 weeks of age in Korean native dogs. The results were summarized as follows; 1. Gonocytes were seen at 16 weeks of age, however they were not observed as from 20 weeks of age. Both type A and type B-spermatogonia occurred from 20 weeks, while primary spermatocytes were found from 20 weeks. Secondary spermatocytes and spermatids appeared from 28 weeks. Spermatozoa were observed at first at 28 weeks of age. 2. Type A-spermatogonia appeared approximately 1.6 times as many at stage II compared to stage I, while the same numbers of cells were seen in both stage I and VII, showing the least number among VIII stages of the cycle of the seminiferous epithelia. The type B-spermatogonia were found from stage VI to VIII, Leptotene phase of the primary spermatocyte divided from type B-spermatogonia in stage VII observed at the stage VIII. Pachytene phase of the primary spermatocytes were shown the least in number at stage IV. The secondary spermatocyte could be seen only at stage IV. 3. The relative frequency of each stage from stage I to VIII of the cycle of the seminiferous epithelia was 30.3, 12.0, 9.8, 4.2, 8.5, 10.5, 11.4 and 13.4% respectively. Thus the establishment of spermatogenesis in Korean native dog was completed from 28 weeks of age.

• 한국해양생명과학회지
• /
• 제6권1호
• /
• pp.23-30
• /
• 2021

북방전복 Haliotis discus hannai 웅성생식세포의 분화과정과 정자의 형태를 미세구조적으로 기재하였다. 정자의 분화과정은 정원세포기, 정모세포기, 정세포기 및 정자기의 4단계로 구분하였다. 정원세포기에서 정모세포기로의 분화과정은 형태학적 변화가 크지 않았다. 그러나 정자변태과정 동안 염색질 응축, 핵의 형태 변화, 첨체와 중편 및 편모 형성 등의 급격한 형태학적 변화를 나타냈다. 북방전복의 정자는 두부, 중편 및 미부로 구성되며, 두부의 길이는 약 5.3 ㎛로 전자밀도가 높은 핵과 총알형의 첨체로 이루어져 있었다. 중편은 기저체와 미토콘드리아로 구성되어 있었으며, 기저체를 중심으로 5개의 미토콘드리아가 한 층으로 배열되어 있었다. 미부의 횡단면은 "9+2"의 미세소관 구조를 보였다. 이러한 형태 및 구조적 특징은 북방전복의 정자는 원시형(primitive type) 정자임을 보여주는 결과이다.

• 한국임상수의학회지
• /
• 제16권2호
• /
• pp.448-453
• /
• 1999

The three-dimensional structure of the Sertoli cell in the Korean native bull was investigated by scanning electron microscopy. Morphologically, four types of Sertoli cell processes were evident: 1) sheet-like processes, 2) sleeve-like processes, 3) bough-like processes and 4) finger-like processes. The sheet-like processes rested upon more than half of the surface of each spermatogonia, spermatocyte and spermatid. Sleeve-like processes, bough-like processes and finger-like processes are observed in the middle and apical portion of seminiferous tubule. All Sertoli cell processes are originated from Sertoli cell column. Just before spermiation, the apical sheet-like processes are shifted from their position at the spermatid head, and bough-like processes covered the disengaged residual body, after which the residual body was no longer evident in the tubule. Though the mechanism for this elimination is not known, the process suggests a reciprocity between the Sertoli and germ cells.

• BMB Reports
• /
• 제45권1호
• /
• pp.7-13
• /
• 2012

Phospholipase D (PLD), a superfamily of signaling enzymes that most commonly generate the lipid second messenger Phosphatidic Acid (PA), is found in diverse organisms from bacteria to man and functions in multiple cellular pathways. A fascinating member of the family, MitoPLD, is anchored to the mitochondrial surface and has two reported roles. In the first role, MitoPLD-generated PA regulates mitochondrial shape through facilitating mitochondrial fusion. In the second role, MitoPLD performs a critical function in a pathway that creates a specialized form of RNAi required by developing spermatocytes to suppress transposon mobilization during meiosis. This spermatocyte-specific RNAi, known as piRNA, is generated in the nuage, an electron-dense accumulation of RNA templates and processing proteins that localize adjacent to mitochondria in a structure also called intermitochondrial cement. In this review, we summarize recent findings on these roles for MitoPLD functions, highlighting directions that need to be pursued to define the underlying mechanisms.

• 한국연초학회지
• /
• 제21권2호
• /
• pp.171-181
• /
• 1999

We examined the ultrastructure of eupyrene and apyrene spermatogenesis in the testis of Helicoverpa assulta (Lepidoptera: Noctuidae). The spermatogenesis was progressed near the fringe adjacent to the follicular layer of the testicular follicle, surrounding the apical cell concentrically. Eupyrene and apyrene were firstly distinguished at the telophase stage of the primary spermatocyte. Chromatin was evenly scattered in eupyrene nuclei, whereas it was lumped near the nuclear envelope in apyrene spermatogenesis. Then, the nucleus of eupyrene was transformed into two daughter nuclei by meiosis, while the nucleus of apyrene was divided into many micronuclei by irregular meiosis. After the meiosis was completed, a number of mitochondria in the cytoplasm of the early spermatids of the eupyrene and the apyrene were fused into one nebenkern. Also, as axial filament was formed due to the elongation of the spermatid, the nebenkern became splitted into mitochondrial derivatives. An acrosome precursor was present only in the eupyrene, attached to nuclear envelope.