• The Korean Journal of Physiology and Pharmacology
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• 제14권4호
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• pp.213-221
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• 2010

The hypothalamic-pituitary-adrenal (HPA) axis is the primary endocrine system to respond to stress. The HPA axis may be affected by increased level of corticotrophin-releasing factors under chronic stress and by chronic administration of monosodium glutamate (MSG). The purpose of this study was to investigate whether chronic MSG administration aggravates chronic variable stress (CVS)-induced behavioral and hormonal changes. Twenty-four adult male Sprague-Dawley rats, weighing 200~220 g, were divided into 4 groups as follows: water administration (CON), MSG (3 g/kg) administration (MSG), CVS, and CVS with MSG (3 g/kg) administration (CVS＋MSG). In addition, for the purpose of comparing the effect on plasma corticosterone levels between chronic stress and daily care or acute stress, 2 groups were added at the end of the experiment; the 2 new groups were as follows: naive mice (n=7) and mice exposed to restraint stress for 2 h just before decapitation (A-Str, n=7). In an open field test performed after the experiment, the CVS＋MSG group significant decrease in activity. The increase in relative adrenal weights in the CVS and CVS＋MSG group was significantly greater than those in the CON and/or MSG groups. In spite of the increase in the relative adrenal weight, there was a significant decrease in the plasma corticosterone levels in the CVS＋MSG group as compared to all other groups, except the naive group. These results suggest that impaired HPA axis function as well as the decrease in the behavioral activity in adult rats can be induced by chronic MSG administration under CVS rather than CVS alone.

• Endocrinology and Metabolism
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• 제33권4호
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• pp.466-472
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• 2018

Background: Thyroid dysfunction is associated with negative neonatal and obstetric outcomes. Large differences in thyroid function reference intervals exist across different populations. These differences can be explained by population-specific factors, such as iodine status. Many countries in Latin America report iodine sufficiency, but relatively few countries have published up-to-date data on iodine levels and thyroid function in the overall population, and especially in pregnant women. We evaluated the iodine status of pregnant women in Chile and determined thyroid hormone reference ranges in this population. Methods: This was a prospective observational study of healthy Chilean women at their first prenatal visit before week 14. Thyroid-stimulating hormone (TSH), total thyroxine ($T_4$), free $T_4$, antithyroid peroxidase antibody (TPOAb), and iodine levels from spot urine samples were measured. Iodine status and the reference ranges for TSH were calculated. Results: A total of 1,022 pregnant women in the first trimester were selected. Urinary iodine levels were measured in 302 randomly-selected women. The median urinary iodine concentration was $173.45{\mu}g/L$ (interquartile range, 108.11 to 249.35).The reference ranges of TSH were calculated in 670 patients selected according to the National Academy of Clinical Biochemistry guidelines. The median TSH level was $1.88{\mu}IU/mL$ (2.5th percentile: 0.13 to 97.5th percentile: 5.37). Using the reference range in the 1,022 women, the prevalence of clinical hypothyroidism was 1.76%, and that of subclinical hypothyroidism was 3.92%. TPOAb positivity was more common in women with TSH levels above $3.5{\mu}IU/mL$. Conclusion: We found adequate iodine intake and a right-shifted distribution of serum TSH levels in pregnant women in Chile. The prevalence of hypothyroidism in our sample of pregnant women was higher than has been described in the literature.

• Clinical and Experimental Reproductive Medicine
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• 제32권2호
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• pp.155-164
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• 2005

Objective: This study was performed to investigate the effects of pioglitazone, an insulin sensitizing agent, on insulin resistance, ovarian function and intraovarian stromal blood flow in patients with polycystic ovarian syndrome (PCOS). Material and Methods: Thirty patients with PCOS, aged 18~34 years, were recruited. Criteria for diagnosis of PCOS were as defined in 2003 Rotterdam consensus. They were treated for 6 months with pioglitazone at a dose of 30 mg/day orally. The hormonal blood profile, fasting serum glucose levels, a glycemic response to 75 g oral glucose tolerance test (OGTT), and an ovarian stromal artery (OSA) blood flow were assessed at baseline and after 6 months of treatment. Results: Eighteen (60.0%) of 30 patients treated with pioglitazone demonstrated a spontaneous ovulation After pioglitazone treatment, fasting insulin concentrations, serum glucose levels after 75 g OGTT significantly decreased (p=0.001, p=0.04, respectively), and fasting glucose to insulin (G/I) ratio significantly increased (p<0.001). The pioglitazone treatment induced a significant reduction in serum LH, testosterone (T) and free T levels (p<0.001, p=0.02, p=0.002, respectively). The resistance index (RI) values of OSA significantly increased after treatment (p<0.001). In analyzing pioglitazone-treated patients according to their body mass index (BMI), nonobese group as well as obese group showed a significant improvement in fasting G/I ratio (p<0.01). The pioglitazone treatment induced a significant reduction in serum LH and free T levels in nonobese group (p<0.001, p<0.05, respectively) as well as obese group (p=0.001, p<0.05, respectively). The RI values of OSA significantly increased in both nonobese and obese groups after pioglitazone treatment (p<0.001, p=0.003, respectively). Conclusions: Pioglitazone could ameliorate the glycoinsulinemic metabolism, and this beneficial effects of this drug could improve the endocrine-reproductive condition associated with the decrease of ovarian stromal artery blood flow, in both nonobese and obese patients with PCOS.

• 한국가축번식학회지
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• 제20권4호
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• pp.379-384
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• 1997

외인성 성선자극 호르몬에 의한 과배란처리는 난모세포의 질, 수정, 배발달, 착상, 임신유지 등에 해로운 영향을 수반하는 광범위한 배란전후의 호르몬 분비이상을 야기한다. 최근 본 연구에서 흰쥐에서의 IGF-1이 착상전 및 자궁의 환경적 조절에 미치는 잠재적 역할을 확인하였다. 그 결과는 IGF-1이 아마도 탈락막의 조절과 배발달에 적합한 자궁환경유지에 중요한 역할을 수행한다는 것을 보여주었다. 과배란후 배의 손실과 착상의 실패는, 본 연구에서 관찰되었듯이 부분적인 자궁내 IGF-1의 작용저해에 기인하리라 사료된다. 또한 본 연구진들은 생쥐의 배에서 염색체 이상빈도에 대한 과배란을 유도하는 성선자극 호르몬의 영향에 대한 연구를 수행하였다. PMSG 5, 10 및 15 I.U.를 투여하여 과배란된 생쥐에서 생쥐의 수정란과 8-16 세포기 배의 염색체 분석을 실시하였다. 이수체(aneuploidy), 다배체(polyploidy) 또한 염색체의 구조적 이상은 4개군에서 관찰되었따. 그러나 다배체만이 과배란과 상관관계가 있엇따. PMSG 10, 15 I.U. 처리군에서 다배체 발생율은 각각 2.9%와 10.5%였다. 더욱이 PMSG 용량에 따른 배의 다배체 발생빈도 사이에는 투여량에 따른 상관관계가 확인되었다(P<0.0001). 과배란과 성선자극호르몬은 양의 상관관계가 있었으며 염색체와 과배란의 정도에는 투여량에 따른 상관관계가 있었다. 과배란된 난모세포의 발달 잠재력은 모축의 내분비적 환경뿐만 아니라 생존에 필요한 내인성 요인들 즉 유전적 상태 그리고 난자의 전체적 성숙등에 연관되어 있다고 사료된다.

• 한국가축번식학회지
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• 제21권2호
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• pp.197-205
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• 1997

Improved hypophysectomy technique and the efficacy of bGH in hypophysectomized female rats were studied as a basis for the function of endocrine gland and hormones. 1. With improved sublaryngeal a, pp.oach by hypophysectomy, 34 rats out of 40 were successfully hypophysectomized(more than 80% of success). The surgical time for hypophysectomy per rat was taken about 3.0$\pm$1.0 min. 2. For the effect of hypophysectomy and bGH on body weight gain among the 5 gruops of A, B, C, D, and E, the weight gains for A, B, C, D, and E, were 93g, 9.2g, 10.7g, 25.1g and 36.2g, respectively, which implied that hypophysectomy had a major effect on body weight. And also, the effect of bGH was paralleled with the level of bGH. There were significant difference between control and hypophysectomized groups, and between the bGH treated and bGH non-treated groups after hypophysectomy(p<0.01). 3. For the effect of hypophysectomy and bGH on the length of femur, tibia, humerus, and anterbrachi, longest was for A, shortest for B, and longer in order of C, D, and E. The A group was significantly longer than B, C, D, and E groups. The B group was shorter than C, D, and E groups(p<0.01). 4. For the effect of hypophysectomy and bGH on the weight of femur, tibia, humerus, and antebrachi, heaviest was for A, lightest for B, and heavier in order of C, D, and E. The A group was significantly heavier than B, C, D, and E groups. The B group was lighter than C, D, and E groups(p<0.01). 5. In changes of body length, and weights of liver and heart, A group was most drastically increased. Among the hypophysectomized groups, the change was increased in order of B, C, D, and E. Especially, the change of A group was significantly greater than B, C, D and E gruops. However, no significant differences were found among B, C, D, and E groups. 6. The hypophysectomy in rat had a significant effect on body growth. The effect of hormone was remarkably different depending upon the level of hormone. It was found that 300$\mu\textrm{g}$ of bGH/kg of body wt/day was slightly lower for normal growth.

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1359-1366
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• 2000

An experiment was carried out to study plasma levels of hormones and metabolites of crossbred Holstein cattle during late pregnancy (28 days pre partum), early lactation (30 days post partum), mid-lactation (120 days post partum) and late lactation (210 days post partum). Two breed types of Holstein $Friesian{\times}Red$ Sindhi (50:50 = 50%HF) and Holstein $Friesian{\times}Red$ Sindhi (87.5:12.5 = 87.5%HF) were divided into four groups of four animals each. Two groups of each breed were fed with either rice straw treated with 5% urea or pangola hay (Digitaria decumbens) as the source of roughage throughout the experiments. There were a substantial increases in the mean levels of total triiodothyronine ($T_3$), insulin and glucagon at the onset of lactation, and maintained in a high levels during lactation advance for all groups of experiments. The mean levels of prolactin and thyroxine ($T_4$) were not significantly different among groups of animals, but the plasma cortisol concentration was slightly higher in both groups of 50%HF in comparison with those of 87.5%HF animals. The mean levels of plasma growth hormone (GH) of both groups of 87.5%HF animals feeding on either hay or urea treated rice straw markedly rose in the early period of lactation and markedly reduced in mid- and late lactation. These changes were accompanied with changes of milk yield. In contrast to 50%HF animals, plasma GH levels were considerably higher in the late pregnant period than in the early period of lactation and it remained constant as its value at the early lactation throughout the experimental period. The high levels of both plasma progesterone and estradiol concentration significantly declined after parturition and remained low through lactating period. The plasma glucose level in the 50%HF animals feeding on either hay or urea treated rice straw was higher than the 87.5%HF animals in all periods of experiments. Changes in plasma FFA levels of both types of crossbred animals were depended on the endocrine status during late pregnancy and lactation. The levels of plasma FFA of 50%HF animals were significantly higher (p<0.05) than those of 87.5%HF animals during late pregnancy. Both plasma ${\beta}$-hydroxybutyrate and lactate concentrations were not affected by feeding on either hay or urea treated rice straw during late pregnancy and lactation. These data demonstrate that there were no differences in the physiological performances in the same crossbred animals fed either hay or urea treated rice straw. The 87.5%HF animal has the genetic potential for a high milk yield and homeorhetic adaptation for mammary function differed from 50%HF animals during periods of lactation. Altering lactation persistency in 87.5%HF is regulated mainly by chronically acting growth hormones through the period of lactation.

• 한국동물학회지
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• 제32권3호
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• pp.275-280
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• 1989

본 연구는 한우에서 적출한 시상하부조직을 superfusion 하여 체외배양 하면서 in vitro LHRH의 내인성 분비양상을 조사하였으며, 한우의 in vitro LHRH 분비양상과 수입소인 홀스타인 젖소의 LHRH 분비양상을 비교하였다. 시상하부의 median eminence조직을 적출하여 조각을 내어서 superfusion chamber에 넣은 후 37$^{\circ}C$ 배양기에서 배양하였다. superfusion은 4시간동안 계속되었으며, 10분간격으로 분획을 받아내어 LHRH 분비능을 LHRH방사면역 측정법으로 측정하였다. LHRH 분비 양상의 특성은 PULSAR algorithm으로 분석하였다. 한우와 수입 젖소에 있어서 내인성 LHRH분비는 맥동적인 양상을 보였다. 한우에 있어서 LHRH 분비의 평균분비, 펄스의 진폭과 그 간격은 11.08 $\pm$ 1.50 pg/min/mg x 10-$^2$, 21.43 1 7.28 pg/mg x 10-$^2$, and 39.42 $\pm$ 3.08 min이었고 이 값은 홀스타인 젖소에서의 측정치와 거의 유사하였다. 이와 같은 한우의 펄스 발신기의 기본적인 특징은 한우의 신경내분비적 연구에 중요하리라 사료된다.

• 한국식품영양과학회지
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• 제38권12호
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• pp.1724-1731
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• 2009

마카, 홍삼, 남가새 추출물을 일정한 무게 비율로 혼합하여 발효시켜 얻어진 식물추출복합발효물(MP119)이 성기능에 미치는 영향을 조사하였다. ACE(angiotensin converting enzyme)과 PDE(phosphodiesterase)에 대한 저해효과를 통해 혈액순환부진 개선 및 cGMP 농도에 의한 발기능 개선에 미치는 효과를 측정하였다. MP119의 ACE 저해효과를 측정한 결과 $IC_{50}$값이 241.3${\pm}$35.5 ppm, PDE 저해효과를 측정한 결과 $IC_{50}$값이 372.2${\pm}$33.8 ppm으로 나타나 혈관확장으로 인한 혈류량 증가 및 cGMP농도 증가에 영향을 줄 수 있을 것으로 예상된다. MP119는 마우스 정소세포인 TM3 cell에 유의성 있는 독성이 나타나지 않았으며, TM3 cell에 농도별로 처리했을 때 세포배양액으로부터 대조군과 비교하여 최대 20.11% 증가한 testosterone 농도를 확인하였다. 또한 HUVEC에 농도별로 처리했을 때 NO생산량이 MP119 처리 농도가 증가할수록 유의성 있게 증가하였다. 웅성마우스에 MP119를 7일간 경구투여 후 생식장기의 무게와 정자수를 측정하고, MP119를 경구투여한 후 염화카드뮴을 투여하여 생식장기의 무게와 정자수를 측정하였다. 또한 실험쥐로부터 혈청을 분리하여 혈청 내 testosterone과 cGMP를 측정하였다. 그 결과 MP119의 투여를 통해 생식장기의 무게 변화 없이 정자수 증가에 도움을 준다는 것을 확인하였으며, 더불어 혈청 내 testosterone 및 cGMP의 농도 역시 증가하였다. MP119를 투여한 후 염화카드뮴을 투여한 실험군에서 역시 정자수 및 혈청 내 testosterone, cGMP 농도 증가를 나타내었으므로 결과적으로 MP119가 염화카드뮴의 독성예방 및 치료에 효과적임을 확인하였다.

• Toxicological Research
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• 제20권3호
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• pp.195-203
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• 2004

4-Tert-Octylphenol (OP) is a surfactant additive widely used in the manufacture of a variety of detergents and plastic products. OP can disrupt endocrine function in humans and animals. This study was carried out to obtain toxicokinetic parameters of OP in male Sprague-Dawley (SD) rats. Male rats were administered with OP by single oral application of 200 mg/kg body weight. Blood, urine and tissues samples were taken at several time intervals after administration. Analysis of samples for OP was performed by column-switching high performance liquid chromatography (HPLC). In addition, we exam-ined tissue distribution and accumulation of OP after single oral application of 50, 100, and 200 mg/kg, single intravenous injection of 1, 5 and 10 mg/kg or daily application of 50 mg/kg for 14 consecutive days. After single oral administration of 200 mg/kg, Cmax of 213 $\pm$ 123 ng/ml was reached within the first 1.3 hr (Tmax) in the plasma. AUC was calculated for 1,333$\pm$484 ngㆍhr/ml. The final elimination half-life of plasma was longer than that of urine, but urinary clearance was lower than oral. A very small fraction of OP (Fe < 0.0017%) was excreted in urine within 24 hr. These results indicated that the major excretion route of OP was not urine. The mean maximal tissue distribution of OP was obserbed at 6 hr after treatment and slowly decreased time-dependently. High OP concentrations were detected in fat at 24 hr. The OP in fat was slowly released with longer elimination half-life and lower clearance than that of other tissues. OP was not accumulated in the liver following single oral application but 14-day oral treatments resulted in two-fold accumulation. It was probably due to the saturation of detoxification pathways. On the other hand, the mRNA expression of cytochrome P450 isoforms except CYP2C11 was not affected by OP at any dose. The expression of CYP2C11 mRNA decreased in a dose-dependent manner. This result suggests that OP changes expression of the male-specific cytochrome P450 isoforms in rat liver, and these changes are closely related to the toxic and estrogenic effect of OP.

• 한국발생생물학회지:발생과생식
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• 제5권2호
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• pp.107-114
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• 2001

환경호르몬(내분비계 장애물질)이 하등동물의 생식기 및 생식 기능 이상을 초래한다는 최근보고는 포유동물도 그 영향하에 있음을 암시한다. 따라서 2-bromopropane(2-BP)이 생쥐 차산자의 성별에 미치는 영향과 성 분화 과정 중에 발현되는 유전자를 조사하였다. 생쥐를 2-BP로 3주일 동안 주입한 암수를 4종류 조합으로 교배시 킨 후 태어난 새끼들의 성별을 이유시기에 결정하였다. 성관련 유전자들은 수태 후 10일에 어미 생쥐를 희생시켜 RT-PCR 방법으로 태자들에게서 발현되는 유전자를 탐지하였고, 동정된 범위의 핵산 서열을 기존의 보고된 서열과 비교 분석하였다. 이유시기까지 살아남은 한배 차산자 평균수는 암수를 모두 2-BP로 처리한 군에서만 약간 감소하였다. 차산자의 성비에서 암컷 어미가 2-BP로 처리된 군에서만 차산자 암컷이 수컷보다 많았으며, 그 이외의 군에서는 수컷이 암컷보다 많았다. 성 분화 시기에 발현되는 유전자들인 SRY 유전자는 416 염기, DAX1 유전자는 466 염기, SF1 유전자는 326 염기, AMH 유전자는 389 염기를 동정하였다. 이 유전자들은 흰쥐와는 89～90％의 상동성을, 그리고 사람과는 81～92％의 상동성을 보였다. 이 유전자들은 성이 결정되는 시기인 수태 10 일경에 모두 발현됨을 알 수 있었다. 따라서 2-BP는 생식능력에 어느 정도 영향을 미치는 것으로 사료된다. 포유동물의 성 분화에 미치는 내분비계 장애물질의 영향을 성관련 유전자들의 발현과 관련지어 연구할 수 있을 것으로 기대된다.