• 한국환경과학회:학술대회논문집
• /
• 한국환경과학회 1996년도 봄 학술발표회 초록집
• /
• pp.51-51
• /
• 1996

• 한국발생생물학회지:발생과생식
• /
• 제20권3호
• /
• pp.247-254
• /
• 2016

Cytological changes of the epithelial cells according to the developmenatal phases of the seminal vesicle related to the spermatogenic stages in the testicular lobules during spermagenesis in male Neptunea (Barbitonia) cumingii (Gastropoda: Buccinidae) were investigated monthly by electron microscopical and histological observations. N. (B) cumingii is dioecious, and an internal fertilization species. The male genital organ is located near the tentacles. The spermatozoon is approximatley $50{\mu}m$ in length. The axoneme of the tail flagellum consists of nine pairs of microtubles at the periphery and one pair at the center. The process of germ cell development during spermatogenesis can be divided into five succesive stages: (1) spermatogonia, (2) primary spermatocytes, (3) secondary spermatocytes, (4) spermatids, and (5) spermatozoa. A considerable amount of spermatozoa make their appearance in the testicular lobules (or acini) and some of them are tranported from the testis towards the seminal vesicles until late July. In this study, the developmental phases of the epithelial cells of the seminal vesicles of N. (B.) cumingii could be classified into four phases: (1) S-I phase (resting), (2) S-IIphase (early accumulating), (3) S-III phase (accumulating), and (4) S-IV phase (spent). However, in case of N. (B.) arthritica cumingii, the developmental phases of the seminal vesicle were devided into three phases: (1) resting, (2) accumulating and (3) spent. Granular bodies in the inner layer of the seminal vesicles are involved in resorption of digestion of residual spermatozoa.

• 한국가축번식학회지
• /
• 제11권1호
• /
• pp.33-41
• /
• 1987

The cycle of the seminiferous epthelia in the testis of matured Korean Native Cattle was divided into eight stages. The results were summarized as follows: 1. Type A spermatogonia a, pp.ared twice as many at stage 2 as compared to stage 1, while maximum numbers were the average of 2.8 at stage 2. The intermediate and Type B spermatogonia were found during the stage 3 to 8, stage 6 to 8, respectively. The leptolene primary spermatocytes were not observed during the stage 5 to 7, while the pachytene primary spermatocytes were shown the least in number at stage 4, the secondary supermatocytes could be seen only at stage 4 and the round spermatids were not observed at stage 3, 4. 2. The relative frequencies of the eight stages of the cycle of the seminiferous eptithelia were 24.9, 14.2, 19.0, 6.3, 3.7, 7.9, 10.3 and 13.9%, respectively. 3. Some of the nuclei of Sertoli cells transformed from the "parallel" type to the "perpendicular" type. This evolution took place from stage 1 to 5, when the number of "perpendicular" type nuclei reached a peak and the number was decreased in the rest of the stages.sed in the rest of the stages.

• Reproductive and Developmental Biology
• /
• 제39권2호
• /
• pp.43-47
• /
• 2015

Sirtuin proteins are evolutionary conserved Sir2-related $NAD^+$-dependent deacetylases and regulate many of cellular processes such as metabolism, inflammation, transcription, and aging. Sirtuin contains activity of either ADP-ribosyltransferase or deacetyltranfease and their activity is dependent on the localization in cells. However, the expression pattern of Sirtuins has not been well studied. To examine the expression levels of Sirtuins, RT-PCR was performed using total RNAs from various tissues including liver, small intestine, heart, brain, kidney, lung, spleen, stomach, uterus, ovary, and testis. Sirtuins were highly expressed in most of tissues including the testis. Immunostaining assay showed that Sirt1 and Sirt6 were mainly located in the nucleus of germ cells, spermatocytes, and spermatids in the seminiferous tubules, whereas Sirt2 and Sirt5 were exclusively present in the cytoplasm of germ cells and spermatocytes. Our results indicate that Sirtuins may function as regulators of spermatogenesis and their activities might be dependent on their location in the seminiferous tubules.

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

• 한국환경과학회지
• /
• 제7권5호
• /
• pp.599-605
• /
• 1998

The purpose of this work was to examine whether X-Y chromosome dissociation in the primary spermatocytes of mice could be used as an in vivo short-term assaying system that detect environmental mutagens. Four alkylating agents(EMS, MMS, MMC and MNNG) which were known as strong mutagens were administered to BALB/c male mice 3-4 months old. In the control group, the mean frequencies of previously dissociated X and Y chromosomes and autosomes were 7.17% and 2.12%, respectively. Compared to the control group, mutagen-treated groups have no significant differences in dissociation rate of autosomes, while these poops were about 1.2-2.5 times higher in the frequencies of X-Y dissociation. Generally, X-Y dissociation frequency increased consistently with the concentration of mutagens whereas the tendency of autosome dissociation frequency was variable among several mutagens. These results suggest that X-Y dissociation in the primary spermatocytes of mice is applicable as an vivo short-term assaying system for environmental mutagens. There were significantly distinct increase in dissociation of X-Y chromosome in both the hybrid and parents but the X-Y previous dissociation of hybrid appeared higher frequency than BALB /c and wild mice. These results indicate that the factor related to binding X-Y chromosome is specific to strains.

• Asian-Australasian Journal of Animal Sciences
• /
• 제29권6호
• /
• pp.793-800
• /
• 2016

Most hinnies (female donkey${\times}$male horse) and mules (female horse${\times}$male donkey) are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean number of seminiferous tubules was significantly higher in stallion and hinny than Jack donkey (p<0.01), the mean proportion of seminiferous tubules was lower in the hinny (p<0.01) which resulted in a smaller diameter of seminiferous tubules. The mean number of spermatogonia and spermatocytes per unit area were significantly lower in hinny testis (p<0.01) and no spermatids or mature spermatozoa cells were found during immunofluorescent analyses. These results indicated that defects in seminiferous tubule development and structure occur in the testis of hinnies. Furthermore, most spermatogonia and spermatocytes cease development in synapsis during mid-meiosis of spermatocytes, which results in a block to spermatogenesis that prevents the formation of spermatids and matured spermatozoa during meiosis in male hinnies.

• Applied Microscopy
• /
• 제32권2호
• /
• pp.107-119
• /
• 2002

U. unicinctus의 초기 정자형성 과정은 체액 부유성 웅성 생식세포 집단(cluster)에서 수행되는 것으로 관찰되었다. 이들 웅성 생식세포 집단은 체강의 체액 속에 산재하고 다른 체세포와 특정 구조 또는 조직을 형성하지 않았으므로 분산형 정자형성(diffuse spermatogenesis) 또는 단위집단 정자형성 (solitary spermatogenesis) 과정을 거치는 것으로 볼 수 있었다. 단위집단 정자 형성과정은 생식세포들이 체세포와 함께 조직을 형성하는 포유동물의 집단 정자형성(localized spermatogenesis)과 비교하여 미세구조 측면에서 여러 가지 특징을 갖는 것으로 관찰되었다. U. unicinctus의 단위집단 정자형성에서 웅성 생식세포 발생단계는 핵의 크기, 핵질(nuclear matrices)의 위상 그리고 핵 응축도 및 웅성 생식세포 기관의 발달 상태를 고려하여 따로 분류하였다. 정원세포와 제1 정모세포의 차이는 핵질의 위상에서 분명하였고, 정모세포와 정세포는 핵 응축도에서 차이를 볼 수 있었다. 단위집단을 형성하는 시기는 정원세포기로서 각 정원세포 돌기들이 서로 융합한다는 증거를 볼 수 있었다. 제1, 제2 정모세포 그리고 정세포들은 단위집단의 외곽에 부착하고 있었으며 내부에는 웅성 생식세포 응축 과정에 수반되어 분리된 또는 제거된 세포질 성분(cytoplasmic mass)이 채워지는 것으로 볼 수 있었다. 성숙 후 단위집단에서 체강으로 분리되는 시기는 정세포기이며, 체강에서 관찰된 성숙정자는 물질농도에서 구획이 형성된 원반형 첨체, 미토콘드리아와 편모의 구조로 보아서 운동성과 수정력이 있는 것으로 보인다. 이와 같은 단위집단 생식세포 형성은 체액을 통한 간접 방법에 의해 대사 작용에 필요한 정보와 물질을 교환하기 때문에 가능한 것으로 추측하였으며, 이를 응용하면 적절한 양의 체액을 공급하여 in vitro에서 생식세포 배양이 가능할 것으로 사료되었다.

• 한국환경독성학회:학술대회논문집
• /
• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
• /
• pp.120-120
• /
• 2001

방사선 조사는 생물체의 여러 장기에 큰 손상을 일으키며 생식기에도 큰 영향을 미치는 것으로 알려져 있다. 이중 숫컷의 고환내의 분화중인 정모세포는 매우 민감함을 나타내며 그 결과 방사선 조사 정도에 따라 정자의 이상 형태 및 정자수의 감소를 나타내어 무정자증까지 초래할 가능성이 있는 것으로 알려져 있다. 본 실험에는 8주된 Mongolian gerbil 숫컷을 사용하여 5Gy 및 10 Gy(선량률 ： 1 Gy/분)를 조사하였으며 방사선 조사 바로 직후 및 7일에 고환을 채취하였다. (중략)

• Applied Microscopy
• /
• 제24권3호
• /
• pp.55-66
• /
• 1994

This study was carried out to investigate the histological changes of sperm cells in testis, obtained from 100 of 3-year-old male rainbow trout (Oncorhynchus mykiss) collected and analysed from March in 1992 to February in 1993. Especially, the ultrastructural changes of spermatogonia, primary and secondary spermatocytes, spermatids, and spermatozoa were examined to describe the reproductive cycles of this species. The results obtained in this study were as follows: The ultrastructures of the gonadotrophs largely parallel the cyclical changes in the testes. Each nest of cells belongs to one spermatogenetic stage, although nests at different stages can be found within the one lobule. At first keterochromatin is dispersed and then is condensed. In mature gamete, the nucleus is dense and homogeneous. The nuclear membrane appeared at the beginning of differentiation. In spermatogonia, Sertoli cells are located at the periphery of their cytoplasm. In the primary spermatocytes, the small mitochondria are abundant over the outer cytoplasm. During cell differentiation, the cytoplasm decreases and the nucleus increases. In spermatids, the protein masses moved towards the posterior part of the nucleus. In late spermatids, the two large mitochondria are located over the cytoplasm. In spermatozoa, two spheroidal mitochondria (about 145nm long) are situated in parallel between the nucleus and the axoneme. Spermatozoa mitochondria are assembled into an organized sheath surrounding the outer dense fibres and axoneme of the flagellar midpiece. The two centrioles are quite separate and the central pair and sheath complex of the flagellum is inserted into the base of the distal centriole.