• Korean Journal of Veterinary Research
• /
• v.40 no.2
• /
• pp.361-371
• /
• 2000

It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

• Development and Reproduction
• /
• v.11 no.1
• /
• pp.31-41
• /
• 2007

The spermiogenesis of Crocidura shantungensis were studied by electron microscope. All process of spermiogenesis was divided into 11 phases 15 steps, based on the morphological features of the nucleus and cell organelles in cytoplasm of spermatids. The spermatids in Golgi and cap phases were a spherical shape. On the other hand, at the early acrosomal phase they changed into an oval shape, and the tail was created in this phase. In maturation phase, the shapes of spermatid head were thin and longish. Until step 7 the direction of spermatids head turned toward the lumen of the seminiferous tubule. From step 8 to step 15 their heads turned toward the basal lamina. In step 12, the nucleus and acrosome shown maximal elongation. From Step 13 the nucleus of spermatids became flat, simultaneously with flat expansion of the acrosome expanded, and the visible whole lengths of spermatids were tend to be shorten. Spermatid heading which arrived to step 14 was taken the final shape. The nucleus was doing the wedge shape, and the nuclear chromatins condensed completely and homogenized. In the spermiation phase, the spermatids were gradually disconnected from the cytoplasm of the Sertoli cell. In this phase, the acrosome of the spermatids were fully shorten and flat, and the spermatozoa completed the process of heading and the tailing. Considering all the results, the spermiogenesis may be useful information to analyze the differentiation of spermatogenic cells.

• Korean Journal of Agricultural Science
• /
• v.2 no.2
• /
• pp.405-413
• /
• 1975

The objective of this study was to examine the effect of testosterone on the spermatogenesis. Testosterone propionate was administered in 20 mg dose to male rat with 10 days interval for 50 days and the treated rat was compared with normal one in their testis weight and histological changes. The results were as follows: 1. The longer treatment gave the more decreased testis weight. Treated rat for more than 20 days was significantly different from the untreated one. 2. Diameter of seminiferous tubule was significantly reduced in 40 and 50 days treatments. 3. The ratio of disrupted spermatogenesis on seminiferous tubles was significantly increased from 20 days treatment. 4. On volumetric proportion of testicular structure, spermatozoa and spermatid were significantly reduced from 20 and 30 days treatments respectively. Other components in testis were not changed. 5. The administration of testosterone in over dose damages spermatozoa and spermatid more than other components in testis.

• Development and Reproduction
• /
• v.13 no.1
• /
• pp.25-33
• /
• 2009

The cycle of the seminiferous epithelium and development of spermatids of Apodemus speciosus peninsulae were observed using a light microscope. On the basis of developing spermatocyte and spermatid, the cycle of the seminiferous epithelium was divided into 9 stages. Type Ad spermatogonia were appeared in all stages ($I{\sim}IX$). The Ap, In, and B types of spermatogonia were appeared from stage I, II and III, and IV, respectively. In prophase of first meiosis, the leptotene spermatocytes appeared from stage V and VI, zygotene spermatocytes from stages I, II, VII, VIII, and IX, pachytene spermatocytes from stage III to VII, diplotene spermatocytes in the stage VIII, and secondary spermatocytes in stage IX. On the basis of morphology of spermatid head, developing of nuclear and acrosome and the morphological change of cytoplasm, the developing of spermatids was divided into 12 steps. Considering all the results, A. s. peninsulae displayed very similar result with A. agrarius coreae that is allied species when compare correct characters developing of spermatids with spermatogonia and appearance time of the spermatocyte. Appearance time of the same cell and number of spermatogonial generation was thought that characters of the species, and information may be useful in identifying the species.

• Clinical and Experimental Reproductive Medicine
• /
• v.17 no.1
• /
• pp.21-28
• /
• 1990

19-nortestosterone(NORA)와 19-norandrostenedione(NT)는 정소내 aromatization과정중 중간 대사물로 검출된다. 본 연구는 이들을 장기간 투여하여 정소 및 부속기관의 무게, 혈청내 testosterone(T)의 농도, 정자형성에 미치는 영향을 조사하였다. NORA, NT 및 TE를 $300/50{\mu}l$농도로 주당 3회씩 12주간 정소에 직접 주사(intratesticular injection, i.t.)하였다. 또한 GnRH antagonist(RS68439)를 처리하여 혈청내 생식소자극호르몬 (GTH)을 감소시킨후 위 호르몬들을 동일방법으로 처리하여 이들의 보상작용을 조사하였다. NORA는 정소무게를 감소시키지 않았으나 GnRH antagonist를 처리하여 감소된 정소무게를 현저하게 보상하였다(P<0.05). NORA, NT, TE는 모두 부속기관의 무게를 증가시켰으며, RS68439가 감소시킨 부속기관의 무게를 현저히 증가시켰다. 그러나 이들은 부정소(epididymis)에는 영향을 주지않았으며 RS68439처리군에서는 보상작용을 나타내었다. 이들의 처리로 혈청내 LH농도는 완전히 감소하였으나 FSH의 농도에는 영향을 나타내지 않았다. 그리고 혈청내 T의 농도를 증가시켰다. NORA는 정자형성과정중 7단계의 spermatid의 수를 현저히 감소시켰다. 위 결과로 보아 NORA는 GnRH antagonist로 FSH의 분비가 억제된 쥐의 FSH분비를 촉진하며, T의 농도를 증가시켜 정자형성과정을 억제하는 것으로 추론된다.

• Applied Microscopy
• /
• v.16 no.2
• /
• pp.75-91
• /
• 1986

Differentiation of the rat testis was studied by light and electron microscope from the fetal stage up to the newborn or adult stage. The purpose of the present study is to investigate the ultrastructural changes of seminiferous tubules and interstitial tissue during the developmental process. The results were as follows: the seminiferous tubule diameter began to increase from birth and was fully developed at 30 to 40 days of age through intratubular cell proliferations. Basement membrane and myoid cells lining the seminiferous tubules were differentiated at 17 days gestation. At the fetal stage, seminiferous tubules were primarily composed of Sertoli cells and the differentiation of Sertoli and germ cells progressed from the newborn stage. Spermatids and immature spermatozoa are appeared at 40 days of age, so from this time, spermatogenesis occurred actively until the adult stage. Sertoli cells aided germ cell differentiation and phagocytosed the parts of the spermatid cytoplasm. Leydig ce]] development follows a biphasic pattern: a fetal phase and then an adult phase from 20 days of age. In conclusion, the rat testis is already developed to some extent by the fetal stage and is functional after 50 days of age. Therefore, these findings indicate that differentiation of Sertoli and Leydig cells precedes the onset of spermatogenesis.

• Development and Reproduction
• /
• v.19 no.1
• /
• pp.1-10
• /
• 2015

The purpose of the present study was to examine the seminiferous epithelium cycle of Bombina orientalis using a light microscope. The cycle was divided into a total of 10 stages, according to the morphological characteristics of the cells. The spermatogenetic cells included primary spermatogonia, secondary spermatogonia, primary spermatocytes, secondary spermatocytes, spermatid and sperm. At stage I, the primary spermatogonia was located closer to basal lamina of the seminiferous tubule without spermatocyst formations. Especially at the stage II, the secondary spermatogonia were located in the spermatocyst. The primary and secondary spermatocytes were found from stages III to VI. The secondary spermatocytes were smaller in size than the primary spermatocytes, but they had thicker nucleoplasm and smaller nuclei. The round-shaped, early sperm cells were formed in stage VII, and further divided at stage VIII to have more concentrated nucleoplasm before division to matured sperm cells. At stage X, the matured sperm cells emerged from the spermatocyst. Considering the above results, this study presented the special characteristics in the generation and type of sperm formation. The germ cell formation occurred in various stages, like the perspectives of Franca et al (1999), ultimately, providing taxonomically useful information.

• Korean Journal of Animal Reproduction
• /
• v.19 no.4
• /
• pp.271-281
• /
• 1996

1960년대에 본격적인 연구가 시도된 난세포질내 정자직접주입법(Intracytoplasmic Sperm Injection ; ICSI)은 1976년에는 Uehara 등에 의한 hamster의 연구에서 최초로 전핵의 형성에까지 성공하였다. 이후 계속된 연구를 통하여 여러 동물종에서 이 방법에 의한 난자의 수정 및 배발달에 성공하여, 1988년에 토끼, 1991년에 소, 1995년에는 생쥐에서 산자의 생산에 성공하였다. 한편, 사람에 있어서는 1988년 Lanzendorf 등에 의해 최초로 사람난자가 난세포질내 정자직접주입법에 의해 수정에 성공한 것이 보고되었으며, 1992년에는 Palermo 등에 의해 이 방법에 의해 수정된 수정란 이식을 통한 임신 및 성공적인 분만이 보고되었다. 난세포질내 정자직접주입법에 있어서는 정자의 운동성 및 첨체반응 등의 유무가 수정에 관여하는 중요한 요인이 아닌 것으로 알려지고 있으며, 성숙한 정자가 아닌 정소상체(미부-두부)정자 혹은 정소내의 미성숙정자를 사용하여 난세포질내 정자직접주입법을 시행하여도 수정 및 임신이 가능한 것으로 보고되었다. 또한 정자세포(spematid)나 원형정자세포(round spermatid)를 수정과 배발달이 관찰되었으며 사람에 있어서는 분만까지 성공하였다. 현재까지 이 난세포질내 정자직접주입법은 학술적으로는 난자-정자가 결합하는 기전을 밝히는 연구에 이용되어 왔으며, 임상적으로는 시험관아기시술에 있어서 정자의 기능, 수 등이 문제가 되어 수정이 어려운 남성불임환자에게 적용하여 좋은 성과를 거두어 왔다. 향후 이 기술은 유전자진단이나 남성불임환자의 처치에 폭넓게 사용될 것으로 기대된다.

• Biomedical Science Letters
• /
• v.12 no.1
• /
• pp.43-48
• /
• 2006

Present study aimed to investigate recovering effect of propolis on blood components and tissues of mouse after low dose irradiation. It is verified that the contents of Fe, Mg, P, Zn and Cu in propolis dosed blood are increased slightly than irradiated blood, however, the contents of Ba and Pb are decreased to one tenth than irradiated blood and the contents of Fe and P are increased to 10% than control group. We consider this result as the propolis acts a role of defence factor minimizing changes of elements caused by irradiation in blood. Among the blood components, Glutamate oxaloacetate transaminase (GOT) value is increased after the radiation but after dosed with propolis and irradiated the value is decreased, suggesting that propolis as a buffering material against irradiation. After dosed with propolis, a number of spermatogenic cells are lowered in testis tissue, however, nucleus and cytoplasm are clearly observed in spermatogonia, spermatocytes and spermatid cells. And nucleus and membrane of cells in the proximal convoluted tubule of renal tissue are clearly observed. Also, cytoplasmand membrane of surface mucous cells in stomach tissue are appeared in normal which is almost like those of control group. We consider that the propolis used in this study is preventing deformations of cells increasing resistance capacity against irradiation rather than recovering damaged tissues.

• Applied Microscopy
• /
• v.26 no.3
• /
• 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.