• The Korean Journal of Zoology
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• v.33 no.4
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• pp.435-445
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• 1990

Gonadotropin releasing horrnone (GnRH) is known to be extrahypothalamically localized with a broad range including gonad. It remains, however, unknown whether GnRH is locally synthesized in the gonad. The present srudy aims to identity expression and cellular localization of GnRH-Iike mRNA and immunoreactive GnRH in the rat gonad. GnRH radioimmunoassay and chromatographic extracts on G-50 sephadex column showed that rat gonadal extracts contained a substantial amount of immunoreactive GnRH similar to the hypothalamic and synthetic GnRH. Although a wide distribution of immunostainable GnRH-like molecule with different cell types in the rat ovary was observed, the major cell population hybridized with GnRH probe appears to be granulosa. theca cells and corpus luteum. Immunoreactive GnRH-Iike peptides were distributed m various regions of testis, including spermatogenic cells, Sertoli cells and Leydig cells. In situ hybridization revealed that positive signals of GnRH-Iike mRNA were predominandy present in Sertoli cells within some seminiferous tubules, but absent in the outside of seminiferous tubules in the testis. This study clearly demonstrated that GnRH-Iike molecule present in the rat gonad may be resulted from the local synthetic machinery of GnRH supporting the notion that this peptide may act as autocrine and/or paracrine role in intra-gonadal communication.

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

• Environmental Analysis Health and Toxicology
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• v.15 no.4
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• pp.123-130
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• 2000

2-Bromopropane, important industrial chemical, specially in electronic industry at Yangsan in Korea has been reported to cause amenorrhea for female and azoospermia, oligozoospermia or reduced sperm motility for male. 2-BP was investigated through 21 days of repeated dose in male Sprague-Dawley rats. The dose levels per body weight were 0 (control), 250,500 and 1,000 mg/kg. 2-BP dissolved in vehicle olive oil was injected into the intraperitoneum 6 times per week for 3 weeks, but 1,000 mg/kg dose group was 2 weeks because of serious illness. Male rats showed significant decreases in body weight and right and left testis showed typical weight losses depending on the 2-BP. The number of white blood cell and red blood cell , percentage of monocytes, and hemoglobin decreased significantly in high dose (P< 0.05). Red cell volume distribution width increased significantly in the high dose (P< 0.05). Histopathological findings of testes showed a decrease of spermatogenic cells, exfoliation of spermatid and spermatocyte, vacuolization of Sertoli cells and hyperplasia of Leydig cells. Protein band density between 113,000 dalton ($\beta$-galactosidase) and 53,900 dalton (ovalbumin) has decreased in 250 mg/kg dose group, but it has gradually increased to the higher density in 1,000 mg/kg dose group than in control group.

• Applied Microscopy
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• v.32 no.2
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• pp.107-119
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• 2002

Early spermatocytes of U. unicinctus are found in cluster floating in the coelomic fluid. The spermatocytes in a cluster form a syncytium or cytoplasmic mass, but there are no indications that the cytoplasmic mass is a component of a somatic cell. This work suggested that this type of spermatogenesis can be subordinated to solitary spermatogenesis in the sense excluding structural and functional support of a somatic cell for sperm developments. The solitary spermatogenesis in U. unicinctus is different in appearances and developmental details of sperm organelles and stage distributions from that of localized spermatogenesis. The acrosomal rudiments and centrioles can be observed in the early single cells of spermatogonia and clearly disclosed in the primary spermatocyte. In the stage of secondary spermatocyte, the acrosomal precursor and the centrioles begin to move to each cytoplasmic poles. The polarities of the organelles are attained at stage of spermatids. The spermatocytes and spermatids are arranged circumferentially along the cytoplasmic mass in which some amorphological cytoplasmic components are included. The spermatids reveal to be detached from the cytoplasmic mass into coelomic fluid. It suggests that the spermatogenesis are progressed in support of coelomic fluid, and the fact take into consideration that the spermatogenic cells can be in vitro cultured without somatic cells and with supplements of coelomic fluid.

• Development and Reproduction
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• v.7 no.2
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• pp.89-93
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• 2003

The present study observed the ultrastructure of testis of bluespotted mud hopper(Boleophthalmus pectinirostris), and sperrnatogenesis was discussed also. The testis was surrounded by a thin adventitia, inside which spermatocyst composed the parenchyma of testis. Each lobule was enwrapped by many spermatocysts, which were filled with different kinds of spermatogenic cell clusters at the same developmental stage. In the lobule lumen there are large numbers of spermatozoa The thin adventitia(outer wall) of testis was composed of outer epithelium, and the underlying layers, such as collagen fiber layer, and myoid tissue. The myoid tissue elongated into the inside of testis, became the main componentof interstitium between spermatocyst where sperrnatogenesis occurred. In addition interstitial cells containing dense homogeneous nucleus and abundant mitochondria were observed. Spermatogonia contained round nucleus with diffuse chromatin and nucleolus, and dense nuclear bodies surround by mitochondria in cytoplasm. The synaptonemal . complex was observed in primary spermatocytes clearly. Early spermatid presented larger round nucleus composed of granular chromatin, which was located in the center of cytoplasm. The nucleus of mid-spermatid composed of finely granular chromatin lied on one side of spermatid, and abundant mitochondria had migrated another side. A nuclear fossa appeared in the site near mitochondria in late-spermatid, and the centriole was formed in nuclear fossa.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.11
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• pp.1729-1737
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• 2018

Objective: The aim of the current study is to investigate the relationship between prohibitin (PHB), capping actin protein of muscle Z-line beta subunit (CAPZB), and tektin-2 (TEKT2) and sperm motility in Murrah buffalo. Methods: We collected the high-motility and low-motility semen samples, testis, ovary, muscle, kidney, liver, brain and pituitary from Murrah buffalo, and analysed the expression of PHB, CAPZB, and TEKT2 in mRNA (message RNA) and protein level. Results: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) result showed that the expression of PHB was higher and CAPZB, TEKT2 were specifically expressed in testis as compared to the other 6 tissues, and that in testis, the expression of TEKT2 was higher than that of CAPZB and PHB. Immunohistochemistry test revealed that all three genes were located on the convoluted seminiferous tubule and enriched in spermatogenic cells. Both qRT-PCR and Western Blot results showed that the expression levels of PHB, CAPZB, and TEKT2 were significantly lower in the low-motility semen group compared to the high-motility semen group (p<0.05). Conclusion: The expression levels of PHB, CAPZB, and TEKT2 in Murrah buffalo sperm have a high positive correlation with sperm motility. And the three genes may be potential molecular markers for the decline of buffalo sperm motility.

• Korean Journal of Environmental Biology
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• v.32 no.2
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• pp.153-158
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• 2014

In order to determine the testicular cycle of the Korean brown frog, Rana coreana, the gonadosomatic index (GSI) and the changes of germ cells in testis for adult males were investigated throughout the year. The study indicated that the spermatogenesis in the seminiferous tubule of testis began in August and became most active in the month of September, and the GSI was recorded the highest and the cross area of seminiferous tubule was the widest on this period. Furthermore the seminiferous tubules at the post spawning stage appeared in testis during February, and the spermatogenesis was quiescence period of time from March to July and the GSI and the cross area of seminiferous tubule were found to be the lowest. Based on these observations, we suggest that, GSI of male Korean brown frog changes significantly between July to August, indicating the testicular cycle with discontinuous spermatogenic process, and the breeding season was confirmed to be February.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.525-532
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• 2015

In order to determine the testicular cycle of the Asian toad, Bufo gargarizans, adult males of the species were captured around Jeongeup city (Jeollabuk-do, Korea) during March, 2012 to February, 2013 and the gonadosomatic index (GSI) and the changes of germ cells in their testes were investigated throughout the year. The study indicated that the spermatogenesis in the seminiferous tubule of testes began in April and became most active in July. The recorded GSI was the highest and the cross area of seminiferous tubule was the widest in this period. The seminiferous tubules at the post spawning stage appeared in February, the largest amounts occurred in March and primary spermatogonia also appeared in this period. The GSI and the cross area of seminiferous tubules were found to be the lowest in March, indicating a testicular cycle with potentially continuous spermatogenic process. According to the findings above, it is confirmed that testicular spermatogenesis takes place actively between April to July in male Asian toad and that their breeding season is February to March.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.232-236
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• 2002

In an effort to uncover the reproduction of Korean brook perch Coreoperca herzi testis anatomy and sperm morphology were studied. Fish samples were collected in the Sooypcheon river from May to October 2001. White-colored testes have wedgeshaped external morphology, and developed symmetrically in the dorsal cavity of the trunk. Isogenetic germ cells developed in the cyst located in seminiferous lobule. Each lobule showed significant asynchrony in the spermatogenic stage of the cyst. Sperm was 43 ${\mu}$m in length. The round head was 2.2 ${\mu}$m long. The middle piece developed beneath the head was 0.5 ${\mu}$m long. Tail was 40 ${\mu}$m in length. Coomassie brilliant blue (CBB) gave rise the intense staining in the apex of sperm head and middle piece, suggesting the possible development of acrosome.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.4
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• pp.341-354
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• 2021

Cardamonin (CARD) is a chalconoid with anti-inflammatory and antioxidant properties, and it is present in several plants. We sought to explore whether CARD exerts any positive effects against hyperglycemia-induced testicular dysfunction caused by type 2 diabetes and aimed to identify its possible intracellular pathways. Adult male rats were subdivided into six groups: control, CARD, diabetic (DM), DM + glibenclamide (GLIB), DM + CARD and DM + GLIB + CARD. Type 2 DM induced a significant increase in blood glucose and insulin resistance, along with diminished serum insulin, testosterone and gonadotropins levels, which were associated with the impairment of key testicular androgenic enzymes and cellular redox balance. Administration of CARD at a dose of 80 mg/kg for 4 weeks effectively normalized all of these alterations, and the improvement was confirmed by epididymal sperm analysis. After treatment with CARD, the pathological changes in spermatogenic tubules were markedly improved. Significantly, CARD upregulated testicular glucose transporter-8 (GLUT-8) expression and had inhibitory effects on elevated autophagy markers and caspase-3 immunoreactive cells. Furthermore, our results revealed that CARD was able to attenuate damage via activation of Nrf2 through the p62-dependent degradation of testicular anti-Kelch-like ECH-associated protein-1 (Keap-1). In conclusion, this study suggests that CARD provides protection against diabetic stress-mediated testicular damage. The use of CARD with conventional anti-diabetic therapy was associated with improved efficacy compared with conventional therapy alone.