• Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.143-149
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• 2007

This study describes spermatogenesis and sperm ultrastructure of the granular ark, Tegillarca granosa using light and electron microscopy. In the active spermatogenic season, the testis comprises many spermatogenic follicles that contain germ cells in different developmental stages. Primary spermatocytes in the pachytene stage are characterized by synaptonemal complexes. The early spermatids are characterized by the appearance of several Golgi bodies, increased karyoplasmic electron density, and tubular mitochondria. The mass of proacrosomal granules consists of numerous heterogeneous granules with high electron density that are about 20 nm in diameter. From the midstage of spermiogenesis, the well-developed mitochondria in the cytoplasm aggregate posterior to the nucleus and surround the proximal and distal centrioles. The proacrosomal granules condense and form a single acrosome with a thin envelope. During late spermiogenesis, the acrosome begins to elongate becoming conical. The sperm is approximately $35.0{\mu}m$ long and consists of a head, midpiece, and tail. The head comprises a round nucleus and a conical acrosome. A micro fibrous axial rod is observed between the nucleus and acrosome. The midpiece has a calyx-like structure with five mitochondria, and the tail, which has the typical "9+2" microtubular system, originates from the distal centriole.

• Toxicological Research
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• v.17 no.4
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• pp.241-248
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• 2001

Exposure to 2-Bromopropane has been known to cause degeneration of male germ cells. However the mechanism underlying this process is poorly understood. The objective of this study was to determine whether or not the exposure of male Sprague-Dawley rats to 2-BP induces apoptosis in male germ cells. Male rats(N=3 or 4 in each group) were orally administered either with the corn oil vehicle (10 ml/kg body weight) or with 2-BP (3,500 mg/kg) once a day for 3 days. The presence of apoptosis was determined by TUNEL detection in situ and by an increase in DNA fragmentation. A low spontaneous incidence of apoptosis was observed in vehicle control animals, especially in pre-meiotic germ cells of stages I-VI and stages XII-XIV the seminiferous tubules. In 2-BP exposure rats, the incidence of apoptosis markedly increased at 4 h, reached a peak at 8 h (about 7-fold over control), and then decreased rapidly to control level by 48 h after the last administration. Although apoptosis induced by 2-BP occurred in all stages of germ cells, it was most pronounced in spermatogonia and early spermatocytes in stages I-VI and stages XII-XIV. Taken together, our results suggest that apoptosis is involved in the toxicity of testicular germ cells resulting in oligospermia or azoospermia after exposure to 2-BP.

• Molecules and Cells
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• v.28 no.1
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• pp.31-36
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• 2009

Centrobin/Nip2 was initially identified as a centrosome protein that is critical for centrosome duplication and spindle assembly. In the present study, we determined the expression and subcellular localization of centrobin in selected mouse tissues. Immunoblot analysis revealed that the centrobin-specific band of 100 kDa was detected in all tissues tested but most abundantly in the thymus, spleen and testis. In the testis, centrobin was localized at the centrosomes of spermatocytes and early round spermatids, but no specific signal was detected in late round spermatids and elongated spermatids. Our results also revealed that the centrosome duplication occurs at interphase of the second meiotic division of the mouse male germ cells. The centrobin protein was more abundant in the mitotically active ovarian follicular cells and thymic cortex cells than in non-proliferating corpus luteal cells and thymic medullary cells. The expression pattern of centrobin suggests that the biological functions of centrobin are related to cell proliferation. Consistent with the proposal, we observed reduction of the centrobin levels when NIH3T3 became quiescent in the serum-starved culture conditions. However, a residual amount of centrobin was also detected at the centrosomes of the resting cells, suggesting its role for maintaining integrity of the centrosome, especially of the daughter centriole in the cells.

• Applied Microscopy
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• v.44 no.1
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• pp.1-7
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• 2014

The spermatogenesis of Siamese fighting fish, Betta splendens, belongs to Osphronemidae was investigated by light and electron microscopic observations. In primary spermatocyte stage, the nucleus was comparatively large ellipsoidal, and mitochondria showed a marked development in cytoplasm. In secondary spermatocyte stage, the germ cells were smaller than that of primary spermatocytes. The nucleus was a spherical shape and intercellular space was formed between germ cells. In spermatid stage, the early spermatids were not much different from a secondary spermatocyte. But, the chromatin condensation was occurred from the outside to the inside. The nucleus was more condensed. Intracellular space was larger than early spermatid. The mitochondria were rearranged in a middle piece, and occupied about half of the head part in early sperm. In sperm stage, the head of mature sperm was a spherical shape and had no acrosome. The flagellum was showed the typical 9+2 array of microtubules. Also, the tail of sperm had no lateral fins and outer coarse fibers. These ultrastructural characteristics can be used in classification of species.

• Journal of Radiation Protection and Research
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• v.31 no.1
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• pp.31-35
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• 2006

For the purpose of the biological effect in black mouse by neutron irradiation, mice were irradiated with 16 or 32 Gy neutron (flux: 1.036739E+09) by tying flat pose at BNCT facility on HANARO Reactor. And 90 days later of irradiation, physical changes of testis and testis tissue were examined. There were no weight changes but a little bit volume changes and sperm counts in the testes. Atrophy of seminiferous tubules irradiated with 32 Gy neutron is increased in number and severity and those in stage VI showed depletion of spermatogonia and pachytene spermatocytes compared to the non-irradiated control group. Testis damage of black mouse was not recovered after long time by 32 Gy neutron irradiation.

• The Korean Journal of Zoology
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• v.20 no.2
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• pp.67-76
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• 1977

The periodic changes of testis and \ulcorner션 epididymidis in Korean hibernating bats, the oriental discoloured bats (Vesportilio superans Thomas) and the Korean greater horseshoe bats (Rhinolophus ferrumequinum korak Kuroda) were studied in order to clarify the possibility of correlation between their histological findings and one of physiological facets, hibernation, and the results obtained were as follows: 1. The spermatogenic function of the oriental discoloured bats obtained in July and August was depressed although the spermatocytes showed a considerable cell proliferation. Few mature sperms were observed in the seminiferous tubules of the bat obtained in August. 2. The spermatogenic function of the Korean greater horeshoe bats obtained in September was not remalkable but a considerable number of sperms were stored in the excretory ducts which were characterized by existence of para-tubular spaces in the ductus epididymidis. 3. The spermatogenic epithelia of the Korean greater horseshoe bats obtained in December showed histologically atrophied figures. However, a vast number of sperm remained in extremely expaned luminae of the ductuc epididymidis which epithelial cells were maintained rectangular in shape. 4. These results suggest that there are periodic changes of the spermatogenic epithelia and the excretory ducts, and that those histological changes are closely related to their wintering.

• Korean Journal of Veterinary Research
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• v.38 no.1
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• pp.9-15
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• 1998

To investigate the involvement of protein kinase C(PKC) isoenzyme in the testes which control spermatogenesis and hormone secretion, we examined cellular distribution of four types of PKC $\alpha$, ${\beta}I$, ${\delta}$ and ${\theta}$ in the horse testes using PKC antisera by western blot analysis and immunohistochemistry. By the western blot analysis, PKC $\alpha$ and ${\beta}I$ were detected at 82KD, while PKC ${\delta}$ and ${\theta}$ were detected at 80KD in the testes of both juvenile and adult horses. In juvenile horse, PKC $\alpha$, ${\delta}$ and ${\theta}$ except ${\beta}I$ were not detected in the cells of the testes, whereas PKC ${\beta}I$ was immunoreacted with only in spermatocytes. In adult, PKC $\alpha$, ${\beta}I$, ${\delta}$ and ${\theta}$isoenzymes were localized in interstitial cells of the testes. In the seminiferous tubules, PKC ${\beta}I$ is localized in spermatocyte, spermatid and spermatozoa, while PKC ${\delta}$ is localized only in spermatids. We suggest that this is a first report to localize PKC in the testes of horse and PKC isoenzymes are upregulated in the cells of horse testes depending on ages. These findings also suggest that certain PKC isoenzyme plays an important role in the signal transduction of spermatogenic cells and interstitial cells in horse testes.

• International Journal of Oral Biology
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• v.35 no.4
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• pp.137-144
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• 2010

To evaluate the biohazard properties of an extremely low frequency electromagnetic field (ELF-EMF), we explored the physical properties of the ELF-EMF that generates the electric current induction in the secondary coil from the chamber of a primary solenoid coil. We subsequently explored the biological effects of a strong alternating electromagnetic field (EMF), ranging from 730-960 Gauss, on the mouse testis. Mice were exposed to an alternating EMF field induced by a rectangular electric current at 1, 7, 20, 40, and 80 Hertz, for 1, 3, 5, and 7 hours. The mouse testes were examined for proliferative activity and apoptosis using the in situ terminal deoxynucleotidyl transferase (TdT) method and by immunostaining of proliferating cell nuclear antigen (PCNA), respectively. We found that the electric currentm induction increased in the 6-8 Hertz range, and that exposure to an ELF-EMF induced the apoptosis of mouse spermatocytes. In situ TdT staining was found to be most prominent in 7 Hertz group, and gradually reduced in the 20, 40, and 80 Hertz groups. These data suggest that a strong EMF can induce reproductive cell death within a short time, and the harmful effects of the EMF are maximal at low frequency alternating EMFs.

• Advances in Traditional Medicine
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• v.3 no.3
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• pp.133-140
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• 2003

Petroleum ether, chloroform and ethanol extracts of the seeds of Melia azedarach Linn. administered orally to male rats at the dose level of 25 mg/100 g body weight for 48 days showed antispermatogenic activity, as the number of spermatocytes, spermatids and spermatozoa was decreased. The total cholesterol content was increased while protein and glycogen contents were decreased. The acid phosphatase content was also decreased while that of alkaline phosphatase increased. At the same time the weight of caput and cauda epididymis, prostate gland, seminal vesicle and Levator Ani muscle was decreased indicating its antiandrogenic property. Of the three extracts, the petroleum ether extract was more potent in its antispermatogenic and antiandrogenic activities and did not produce any sings of toxicity upto a dose of 25 mg/100 g body weight oral administration. After subjecting it to preliminary phytochemical screening the petroleum ether extract showed positive tests for steroids and saponins.

• Development and Reproduction
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• v.22 no.1
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• pp.65-72
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• 2018

Cyclic AMP-response element binding protein zhangfei (CREBZF), a member of ATF/CREB (activating transcription factor/ cAMP response element binding protein) family, regulates numerous cellular functions and development of cells by interacting transcription factors. This study discovered the expression pattern of CREBZF in seminiferous tubule of testes during the postnatal development of mice. In testis, CREBZF mRNA expression was the highest among other organs. Immunofluorescence analyses showed that the CREBZF was specifically expressed on spermatocyte but not in spermatogonia and Sertoli cells in seminiferous epithelium of mouse testis. Semi-quantitative polymerase chain reaction (PCR) analysis showed that CREBZF transcript level was significantly elevated during postnatal development of mouse testis. Confocal imaging analysis indicated that the protein expression of CREBZF in seminiferous tubule remained low until postnatal day (PD) 14, and was dramatically increased in PD 21. Interestingly, only one type of the spermatocyte expressed CREBZF specifically among SCP3-positive spermatocytes. Taken together, these results suggest that CREBZF may be novel putative marker of the spermatocyte and regulate meiosis during postnatal development of mice.