• 대한생식의학회:학술대회논문집
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• 2001.11a
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• pp.116.2-116.2
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• 2001

• 대한생식의학회:학술대회논문집
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• 2001.06a
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• pp.60-61
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• 2001

• Clinical and Experimental Reproductive Medicine
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• v.17 no.1
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• pp.21-28
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• 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
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• v.16 no.2
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• pp.75-91
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• 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.

• Natural Product Sciences
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• v.14 no.2
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• pp.73-80
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• 2008

The authors screened the pharmacological effects of 50% ethanol extracts of Yacon on spermatogenesis in rats. Numbers of sperm in animals treated with 25, 50, or 100 mg/kg/day for 6 weeks of Yacon tuber extracts (YTE) were approximately 1.51, 1.61 and 1.78 times higher, respectively, than in the untreated control group. Moreover, the spermatogenic effect of Yacon leaf extract was found to be $1.03{\sim}1.38$ times higher than that of YTE. The ameliorative effect of Yacon tuber extracts on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced toxicities in the rat were also investigated. Rats were assigned to three groups (6 rats/group), a control group, a TCDD exposed group, and a group treated with Yacon tuber extract (YTE) after TCDD exposure (TCDD/YTE group). 40 ${\mu}g/kg$ of TCDD was injected i.p., and 200 mg/kg/day of YTE was also administered for 4 weeks by oral gavage. The TCDD/YTE group showed a significant increase in sperm number as compared with the TCDD exposed group. In conclusion, TCDD induced testicular toxicity was significantly ameliorated by YTE. The results of the present study suggest that Yacon extract is a possible therapeutic for the treatment of spermatogenic disorder.

• Biomolecules & Therapeutics
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• v.21 no.2
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• pp.153-160
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• 2013

We screened the pharmacological effects of a 50% ethanol extract of Yacon tubers and leaves on spermatogenesis in rats. As a result, we found that Yacon tuber extracts increased sperm number and serum testosterone level in rats. It has been reported that the crude extract of Yacon tubers and leaves contain phenolic acids, such as, chlorogenic acid, ferulic acid and caffeic acid by HPLC/MS analysis. We were interested in the contributions made by phenolic acid, particularly chlorogenic acid of Yacon tuber extract to the spermatogenic activity. After administering Yacon tuber extract or chlorogenic acid to rats for 5 weeks, numbers of sperm in epididymis were increased by 34% and 20%, respectively. We also administered ferulic acid, which has been reported to be a metabolite of chlorogenic acid and a constituent of Yacon tuber extract to investigate its spermatogenic activity in rats. Yacon tuber extract and ferulic acid increased sperm numbers by 43% and 37%, respectively. And, Yacon tuber extract, and chlorogenic acid showed significantly inhibition effect of testoeterone degradation in rat liver homogenate. We considered that the spermatogenic effect of Yacon tuber extract might be related to phenolic compounds and their inhibitory effect of testosterone degradation. Yacon showed the possibility as ameliorable agents of infertility by sperm deficiency and late onset hypogonadism syndrome with low level of testosterone.

• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.23-36
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• 1993

To investigate the cycle and relative frequences and the fine structure of seminiferous epithelia in mature Jindo dogs, histologic study was performed. The results obtained were summarized as follows; 1. Type A spermatogonia appeared approximately 1.6 times as many at stage II as compared to stage I while type In spermatogonia appeared small amount in stage III, IV and V. type B spermatogonia were found during the stage VI to VIII, though not detectable during stage I to V. The type B spermatogonia divided at stage VII to produce the preleptotene primary spermatocytes at stage VIII. The number of primary spermatocytes of the leptotene phase markedly increased during stage I to II, and the primary spermatocytes of the pachytene phase were shown the least in number at stage IV. The secondary spermatocytes could be seen only at stage IV. 2. The relative frequencies of each stage from stages I to VIII of the cycle of seminiferous epithelia were 31.6, 11.9, 10.0, 3.2, 8.2, 10.1, 11.7 and 13.2% respectively. 3. On electron microscopic observations, acrosomal vesicle of spermatids appeared larger though the bulk of germ cells were the morphologically same as those of the other animal species. Thread line structures light microscopically observed in the cytoplasm of Sertoli cell were the longitudinal orientation of mitochondria.

• The Korean Journal of Zoology
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• v.23 no.1
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• pp.13-24
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• 1980

The germarium contains the apical complex consisting of a multinucleated syncytium. Apical complex has a nutritive role for the early spermatogonia. Trophocytes are irregularly shaped and are distributed throughout the space from spermatogonial cysts to sperm bundles, and they increase in size by endopolyploidization. As meiotic divisions are not complete until the final moult, spermatogenesis continues even in the adult. Chromosome number is 2n=24. Spermiogenesis is divided into seven stages in terms of chromatin concentration, cytoplasmic granules, and the nuclear size and shape. These stages could be grouped into the spherical, the elongating and the rodform spermatids in shape.

• BMB Reports
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• v.38 no.1
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• pp.28-33
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• 2005

A gene coding a novel isoform of carbamyl phosphate synthetase I (CPS1) was cloned from a human testicular library. As shown by cDNA microarray hybridization, this gene was expressed at a higher level in human adult testes than in fetal testes. The full length of its cDNA was 3831 bp, with a 3149 bp open reading frame, encoding a 1050-amino-acid protein. The cDNA sequence was deposited in the GenBank (AY317138). Sequence analysis showed that it was homologous to the human CPS1 gene. The putative protein contained functional domains composing the intact large subunit of carbamoyl phosphate synthetase, thus indicated it has the capability of arginine biosynthesis. A multiple tissue expression profile showed high expression of this gene in human testis, suggesting the novel alternative splicing form of CPS1 may be correlated with human spermatogenesis.

• Development and Reproduction
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• v.14 no.1
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• pp.1-5
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• 2010

We investigated the androgenic effects of 11-ketotestosterone (11-KT) on gonadal sex reversal and spermatogenesis in honeycomb grouper Epinephelus merra by method of gonadal biopsy. 11-KT was injected intramuscularly at a concentration of 1 and $10{\mu}g$ body weight. The proportion of cross sectional area of the gonad occupied by each germ cell type was measured and compared pre- and post-injection group. During the sex change phase, the distribution ratio of oocytes was decreased in all fish of 11-KT treatment group while the distribution ratio of spermatocytes was increased than pre-injection group. In male phase, all fish of 11-KT treatment group shown the increased distribution ratio of spermatocytes, but the distribution ratio of spermatozoa was decreased than pre-injection group. The present results suggest that 11-KT can stimulate degeneration of oocytes, proliferation of spermatocytes and spermiation in honeycomb grouper.