• Environmental Analysis Health and Toxicology
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• 제18권2호
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• pp.95-100
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• 2003

본 연구는 환경호르몬(endocrine disruptors)으로 분류되었으며, 제초제로 널리 사용되었던 Dichlorodiphenyltrichloroethane(DDT)가 설치류의 생식세포 중 Leydig 세포의 testosterone(T)생성억제 및 그 관련 작용메카니즘을 규명코자 수행되었다. 먼저 흰쥐의 웅성 생식세포주인 R2C세포에 T의 양 및 aromatase 활성도를 radio immunoassay (RIA)방법을 이용하여 측정하였다. 그 결과 R2C 세포에 황체형성호르몬(LH)를 처리하여 testosterone생성을 증가시킨 후, DDT를 처리한 군들은 대조군에 비하여 농도 의존적으로 T의 양은 감소하였으며, aromatase 활성도는 증가하였다. 또한 DDT자체만 처리한 군에서도 대조군에 비하여 testosterone의 생성이 감소하였다. 이러한 aromatase활성 증가가 estradiol receptor(ER)와의 상호 관련성을 확인하기 위해 ER antagonist인 ICI 182.780를 처리한 후 T의 양 및 aromatase 활성도를 측정한 결과 DDT에 의해 증가된 aromatase활성도가 ICI 182.780에 의해 다시 감소됨을 확인하였다. 또한 DDT에 의해 감소된 T의 양도 ICI 182.780에 의해 다시 회복되었다. In vivo실험으로 흰쥐에 DDT를 직접 투여한 후 정소 내 성 호르몬들을 측정해 본 결과 T의 양은 유의성 있게 감소하였으며, estradiol(E$_2$)의 양은 증가하였으며, aromatase 활성도도 감소하였다. 이러한 결과를 종합해 볼 때 DDT는 aromatase를 감소시키고, 이렇게 감소된 aromatase에 의해 testosterone 생성량을 억제하고, 이러한 DDT의 aromatase의 감소는 ER을 경유하는 것으로 추정할 수 있다.

• 대한핵의학회지
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• 제16권2호
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• pp.37-47
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• 1982

To evaluate fetal sex-hormonal status before delivery, testosterone and follicle stimulating normone(FSH) levels were measured in 64 amniotic fluid samples at midgestation by radioimmunoassay method. The mean concentration of testosterone in amniotic fluid of 37 cases carrying male fetus was 90.7 pg/ml and 27 cases carrying female fetus was 62.3 pg/ml. The mean :amniotic fluid FSH concentration of male fetus was 1.15 mIU/ml and of female fetus was 11.98 mIU/ml. The amniotic fluid testoserone and FSH concentrations had statistical difference between male and female fetuses. The ratio of testosterone over FSH in the amniotic fluid was 231.2 in male, 9.8 in female respectively and very significant difference was noticed. The levels of testosterone/FSH greater than 25 were found over 92% of male fetus and lesser than 25 were found over 92% female fetus. Measurement of testosterone and FSH especially testosterone/FSH ratio in amniotic fluid in midgestation may be an adjunct to other method of fetal sex determination.

• 동의생리병리학회지
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• 제18권4호
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• pp.1007-1013
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• 2004

The study was conducted to investigate per oral (PO) effects of Raspberry wine on testosterone levels in Sprague-Dawley rats. Raspberry wine of 13% alcohol concentration, was prepared from ripen fruits of Rubus coreanus fermented with Saccharomyces cervisiae. PO administration of Raspberry wine for 15 week (group A) produced dramatic increases of serum testosterone levels. Increase in the testosterone level was observed, using gamma counter with 1251 testosterone, starting from 1 week post administration. Maximum increase in testosterone level was observed at 5 week post administration, 7.486±6.482ng/mL, which was 14.6 times higher than normal and at 15 weeks post administration it was recorded as 1.84±3.516ng/mL. However, PO administration of Saccharomyces cervisiae broth (Group B) and 13% brewed alcohol (group C) for 15 weeks resulted slight increase in testosterone levels, indicating Raspberry wine as an effective phyto-testosogenic beverage of the future.

• Journal of Pharmaceutical Investigation
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• 제39권1호
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• pp.37-41
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• 2009

The purpose of this study was to compare the efficacy of Lorelin Depot $Injection^{(R)}$ (Dongkook Pharm. Co., LTD) with Lucrin Depot $Injection^{(R)}$ (Abbott) by measuring serum testosterone level in rats. Leuprorelin (leuprolide acetate), which is an active compound for the two formulations, is an LHRH analogue that is used for the treatment of a wide range of sex hormone-related disorders including advanced prostatic cancer, endometriosis and precocious puberty. Lorelin Depot $Injection^{(R)}$ is a micro-encapsulated formulation to suppress testosterone level by releasing leuprorelin continuously for four weeks with a single subcutaneous injection. The comparison study of the efficacy was performed during four weeks, and serum testosterone levels were monitored in the two formulations. The mean serum testosterone levels from the formulations were decreased to that of the castrate range (50 ng/dL or less) after three days after the initial depot injection, and the concentration were remained throughout four weeks' period. There were no significant differences in the $AUC_{0-3day}$ of testosterone and testosterone levels at 3, 7, 14, 21 and 28 days between the two formulations. These results indicate that the two formulations, Lorelin Depot $Injection^{(R)}$ and Lucrin Depot $Injection^{(R)}$, are bioequivalent in terms of the serum testosterone level in rats.

• Clinical and Experimental Reproductive Medicine
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• 제30권2호
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• pp.135-139
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• 2003

Objective: We investigated whether serum testosterone to estradiol ratio was decreased in infertile men and whether this condition can be corrected with oral aromatase inhibitor. Method: The serum testosterone to estradiol ratio of 26 men with testicular failure were compared with those of normal semen analysis parameter, 89 control reference group. All of 26 testicular failure group were diagnosed with the previous testicular biopsy. Then 46 men with oligospermia and/or asthenospermia were selected and treated with 1 mg of the aromatase inhibitor anastrozole ($Arimidex^{(R)}$) orally once daily for 3 months. Testosterone to estradiol ratio and semen analyses were evaluated during anastrozole therapy. Results: The testosterone level of testicular failure group was significantly lower and the testosterone to estradiol ratio was more decreased than normal semen parameter group. Forty six on-anastrozole group had significantly lower testosterone (4.6 versus 5.7 ng/ml, p<0.01) and higher estradiol (15.9 versus 23.4 pg/ml, p<0.01) than pre-anastrozole group, resulting in a decreased testosterone to estradiol ratio ($0.21{\pm}0.07$ versus $0.39{\pm}0.15$, p<0.01). Semen analyses before and during anastrozole treatment revealed significant increases in sperm count (35.5 versus 52.2 million sperm per ml, p<0.01) and motility (22.9% versus 29.3%, p<0.01). Conclusions: We identified infertile men with testicular failure had hormonal changes characterized by a decreased serum testosterone to estradiol ratio. The ratio can be corrected with aromatase inhibitor, resulting in a significant improvement in semen parameters.

• The Korean Journal of Physiology and Pharmacology
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• 제12권2호
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• pp.73-77
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• 2008

Recent studies have documented that testosterone relaxes several smooth muscles by modulating $K^+$ channel activities. Smooth muscles of seminal vesicles playa fundamental role in ejaculation, which might involve testosterone. This study was aimed to assess the role of testosterone in seminal vesicular motility by studying its effects on contractile agents and on the ion channels of single vesicular myocytes in a rabbit model. The contractile responses of circular smooth muscle strips of rabbit seminal vesicles to norepinephrine ($10{\mu}M$), a high concentration of KCI (70 mM), and testosterone ($10{\mu}M$) were observed. Single vesicular myocytes of rabbit were isolated using proteolytic enzymes including collagenase and papain. Inside-out, attached, and whole-cell configurations were examined using the patch clamp technique. The applications of $10{\mu}M$ norepinephrine or 70 mM KCl induced tonic contractions, and $10{\mu}M$ testosterone (pharmacological concentration) evoked dose-dependent relaxations of these precontracted strips. Various $K^+$ channel blockers, such as tetraethylammonium (TEA; $10{\mu}M$), iberiotoxin ($0.1{\mu}M$), 4-aminopyridine (4-AP, $10{\mu}M$), or glibenclamide ($10{\mu}M$) rarely affected these relaxations. Single channel data (of inside-out and attached configurations) of BK channel activity were also hardly affected by testosterone ($10{\mu}M$). On the other hand, however, testosterone reduced L-type $Ca^{2+}$ currents significantly, and found to induce acute relaxation of seminal vesicular smooth muscle and this was mediated, at least in part, by $Ca^{2+}$ current inhibition in rabbit.

• 한국발생생물학회지:발생과생식
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• 제21권1호
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• pp.71-78
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• 2017

Nesfatin-1/NUCB2 is known to take part in the control of the appetite and energy metabolism. Recently, many reports have shown nesfatin-1/NUCB2 expression and function in various organs. We previously demonstrated that nesfatin-1/NUCB2 expression level is higher in the pituitary gland compared to other organs and its expression is regulated by $17{\beta}-estradiol$ and progesterone secreted from the ovary. However, currently no data exist on the expression of nesfatin-1/NUCB2 and its regulation mechanism in the pituitary of male mouse. Therefore, we examined whether nesfatin-1/NUCB2 is expressed in the male mouse pituitary and if its expression is regulated by testosterone. As a result of PCR and western blotting, we found that a large amount of nesfatin-1/NUCB2 was expressed in the pituitary and hypothalamus. The NUCB2 mRNA expression level in the pituitary was decreased after castration, but not in the hypothalamus. In addition, its mRNA expression level in the pituitary was increased after testosterone treatment in the castrated mice, whereas, the expression level in the hypothalamus was significantly decreased after the treatment with testosterone. The in vitro experiment to elucidate the direct effect of testosterone on NUCB2 mRNA expression showed that NUCB2 mRNA expression was significantly decreased with testosterone in cultured hypothalamus tissue, but increased with testosterone in cultured pituitary gland. The present study demonstrated that nesfatin-1/NUCB2 was highly expressed in the male mouse pituitary and was regulated by testosterone. This data suggests that reproductive-endocrine regulation through hypothalamus-pituitary-testis axis may contribute to NUCB2 mRNA expression in the mouse hypothalamus and pituitary gland.

• BMB Reports
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• 제43권11호
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• pp.761-765
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• 2010

Salivary testosterone levels in Korean adults were quantitatively measured for the first time by liquid chromatography-electrospray-tandem mass spectrometry (LC ESI MS/MS). Salivary testosterone was separated on a multiple reaction monitoring (MRM) chromatogram within 7 min. The LC ESI MS/MS assay was validated over the linearity range of 0.01-2.00 ng/ml (r=0.99987) using testosterone-$d_3$ as an internal standard. The lower limit of quantification (LOQ) was 0.01 ng/ml. The intra- and inter-assay precisions were 1.54% to 4.09% and 0.96% to 4.29%, respectively. The mean recovery was 93.32% (range 88.43-98.05%). The validated assay was then applied to measure the salivary testosterone levels of Korean adults. In men, the salivary testosterone level collected between 9：00-11：00 am was approximately 2.8 times higher than that in women (P < 0.0001). Salivary testosterone levels in both sexes negatively correlated with age. The present assay would also be useful in measuring salivary testosterone levels in clinical laboratories.

• 생명과학회지
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• 제29권10호
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• pp.1159-1163
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• 2019

남성호르몬 감소와 관련된 남성갱년기에 대한 관심이 고조되고 있지만, 남성호르몬의 정량을 위해 항체를 이용하는 고가의 kit가 이용되고 있다. 본 연구에서는 in vitro 전사 활성 시험법을 이용하여 남성 스테로이드호르몬의 활성 혹은 농도를 검증하는 시스템을 구축하였다. 테스토스테론-AR (androgen receptor) 복합체와 반응하는 ARE-AdE1bTATA 염기서열이 삽입되고 리포터로 luciferase를 발현하는 테스토스테론 유사활성 검증 리포터 플라스미드인 pGL2-Neo-ARE-AdE1BTATA를 제조하고, 인체 전립선암 세포인 LNcap-LN3 세포에 stable transfection을 실시하였다. 구축된 LNcap-LN3/pGL2-Neo-ARE-AdE1BTATA TCD (testosterone compound detection) 시스템은 표준물질인 테스토스테론의 $10^{-13}{\sim}10^{-8}M$ 범위에서 농도 증가에 비례하는 정량성을 보였다. 이 연구에서 확립된 in vitro TCD 시스템을 이용하면 천연물 유래 테스토스테론 유사물질 및 테스토스테론 저하물질의 대량 탐색 등이 가능할 것이므로, 건강기능성 식품이나 의약품 신소재의 개발에 기여할 것이다.

• 한국수정란이식학회지
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• 제9권2호
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• pp.189-196
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• 1994

This study was perfomed to investigate the differentiation of rabbit blastocysts microinjected with testosterone solution. A total of 140 mixed breed does was superovulated, synchronized and hand mated. The eggs were flushed from uterine horns between 65 and 89 hrs after mating. Testosterone was dissolved in 95% ethanol and diluted with PBS at the ratio of 1: 99. Final concentration of testosterone was adjusted to 1 pg /ml. 6~8 bias-tocysts were microinjected with 1~10 p Q of the diluted testosterone solution, and tranfer-red into the uterine horns of the synchronized recipients. When 140 donor does were treat-ed with a single does of 200 IU PMSG in combination with 100 IU RCG 48 hrs apart, 134 of them(97%) showed standing estrus. Ovarian responses of 117 does were examined following mating and the rate of ovulation was 11.23 i 1.20. Ova were recovered from donors between 65 and 89 hrs after mating. Recovery rates of ova were 37.5% and 42.2% of recovered ova were blastocysts. A total of 106 blastsocysts were microinjected with testosterone solution and transferred into the uterine horns of 15 synchronized recipient does. One of the recipients was pregnant and delivered 7 baby rabbits. The external genitalia of the young rabbits appered to be the same appearance as the buck entierly.