• Journal of Animal Science and Technology
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• 제59권7호
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• pp.16.1-16.6
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• 2017

Background: This study was performed to investigate the impact of exogenous ghrelin on the pancreatic ${\alpha}$-amylase outputs and responses of pancreatic proteins to ghrelin that may relate to pancreatic exocrine. Methods: Sprague-Dawley male rats (9 weeks old, $300{\pm}10g$) were injected with ghrelin via intraperitoneal (i.p.) infusion at dosage of 0, 0.1, 1.0 and $10.0{\mu}g/kg$ body weight (BW), respectively. The plasma ghrelin and cholecystokinin (CCK) level were determined using enzyme immunoassay kit; the mRNA expression of ghrelin receptor ($GHSR-1{\alpha}$) and growth hormone (GH) receptor were assessed by reverse transcription PCR; the expressions of pancreatic ${\alpha}$-amylase activity, extracellular-signal-regulated kinases (ERK), phosphorylated extracellular-signal-regulated kinases (pERK) and c-Jun N-terminal kinase (JNK) were evaluated by western blotting; moreover the responses of pancreatic proteins to ghrelin were analyzed using the two-dimensional gel electrophoresis system. Results: The exogenous ghrelin (1.0 and $10.0{\mu}g/kg\;BW$) elevated the level of plasma ghrelin (p < 0.05), and suppressed the expression of pancreatic ${\alpha}$-amylase at a dose of $10.0{\mu}g/kg\;BW$ (p < 0.05). No difference in the level of plasma CCK was observed, even though rats were exposed to any dose of exogenous ghrelin. In addition, a combination of western blot and proteomic analysis revealed exogenous ghrelin ($10.0{\mu}g/kg\;BW$) induced increasing the JNK and ERK expressions (p < 0.05) and four proteins such as Destrin, Anionic trypsin-1, Trypsinogen, and especially eukaryotic translation initiation factor 3 in rat pancreas. Conclusions: Taken together, exogenous ghrelin by i.p. infusion plays a role in the pancreatic exocrine secretion via mitogen-activated protein kinase signaling pathway.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1188-1192
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• 2003

Negative feedback on GH responses to GH-releasing hormone (GHRH) and GH-releasing peptides (GHRPs) has been reported and this action has been suggested to act through an increase in somatostatin. To determine whether the acute administration of porcine GH (pGH) inhibits GH responsiveness to GHRP-2 and GHRH in swine, swine were intravenously administered with pGH (5${\mu}g$/kg BW) or placebo followed 180 min later by a second intravenous administration of saline, GHRP-2 (30 ${\mu}g$/kg BW), GHRH (1${\mu}g$/kg BW) and a combination of GHRP-2 and GHRH. Plasma GH concentration was measured by radioimmunoassay. Administration of pGH caused a significant increase in GH area under curve and GH peak concentrations (p<0.001) over placebo-treated group. Plasma GH concentrations peaked at 15 min and returned to baseline level within 90 min. Pretreatment of pGH abolished (p<0.01) GH response to GHRH and attenuated (p<0.05) GH response to GHRP-2 and GHRH combined, without affecting GH response to GHRP-2. These results demonstrate that negative feedback action on GH releasing effect of GHRH occurs in swine, and that GHRP-2 has ability to interact in this action.

• 대한수의학회지
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• 제51권4호
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• pp.319-323
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• 2011

A 12-year-old spayed female Yorkshire terrier dog was presented with two-weeks history of lethargy, mental dullness and polydipsia. Neurologic examination revealed proprioceptive defect of all limbs and loss of swallowing gag reflex. The dog revealed persistent dehydration, hypernatremia, hyperosmolarity and hyposthenuria. On magnetic resornance imaging (MRI), the mass were heterogeneous signality on T1 weighted images, hyperintense signality on T2 weighted image with contrast enhancement on hypothalamohypophyseal lesion. Based on these findings, the dog was suspected as having pituitary gland tumor. Through water deprivation test and response to desmopressin acetate (1-deamino-8-D-arginine, DDAVP), this case was diagnosed by central diabetes insipidus (CDI). This paper reports the clinical sign, MRI, response to the exogenous antidiuretic hormone of CDI due to suspected pituitary tumor in a dog and DDAVP administration was evaluated effective therapy to correct hypernatremia induced by CDI.

• Journal of Forest and Environmental Science
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• 제34권1호
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• pp.50-52
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• 2018

The effect of basal nutrients concentrations and exogenous auxin for root induction from leaves of Sedum takesimense were investigated for mass-propagation. Root induction rates were significantly different from the concentrations of basal salts but not influenced by supplemented IBA in the medium. The lowest concentration of MS basal salts (1/10) was most effective to induce roots from leaves followed 1/5 MS, and 1/2 and full strength MS medium. Supplement of IBA $10{\mu}M$ in the medium did not improve the root induction that resulted no differences compare to the hormone free media. Rooted leaves were transplanted in soil and survived in greenhouse.

• Asian-Australasian Journal of Animal Sciences
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• 제23권1호
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• pp.13-16
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• 2010

The effect of exogenous administration of tamoxifen (TAM) on hormonal profile and sexual maturity in Indian native Kadaknath (KN) fowl was investigated. Day-old chicks from the same hatch were randomly divided into 15 groups with 20 chicks in each group (5 treatments${\times}$3 replicates). The chicks were placed in battery brooders with wire-mesh floors and reared under uniform husbandry conditions (14 h light/d, 25-32${^{\circ}C}$) on a standard basal diet. At the age of two weeks (wk), birds from the control group ($T_{1}$) were injected with maize oil intramuscularly (I/M), whereas the other four experimental groups $T_{2}$, $T_{3}$, $T_{4}$ and $T_{5}$ were given tamoxifen (I/M) dissolved in maize oil at the rate of 0.5 mg (0.5 TAM), 1.0 mg (1.0 TAM), 2.5 mg (2.5 TAM) and 5.0 mg (5.0 TAM)/kg body weight, respectively, up to 30 wks on every alternate day. At every 6-wk interval, blood samples were collected from nine birds of each treatment group for estimation of estrogen and progesterone. The same birds were sacrificed for determination of the weight of ovary, oviduct, liver and adipose tissue. There was no significant difference in egg production traits except onset of lay and egg number. Low doses of TAM ($T_{3}$) advanced the onset of egg laying by 15 days over the control. Tamoxifen influenced the hormonal profile (estrogen and progesterone) in a dose dependent manner. However, higher doses of TAM suppressed ovary and oviductal growth. From this study, it may be concluded that lower doses of TAM enhanced sexual maturity while higher doses suppressed ovary and oviductal growth.

• 한국발생생물학회지:발생과생식
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• 제9권2호
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• pp.85-93
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• 2005

스테로이드 호르몬인 에스트로겐은 여러 조직의 발생 및 분화에 영향을 주는 것으로 알려져 있다. 최근 에스트로겐의 영향을 평가하는데 있어 전통적인 여성 호르몬이라는 인식을 탈피하여 수컷 생식계상의 역할에 관한 연구가 활발하게 이루어지고 있다. 특히 내분비계 교란물질에 관한 다양한 연구 결과가 보고되면서, 수컷에서의 에스트로겐 역할에 대한 관심이 증대되고 있는 실정이다. 따라서 에스트로겐의 정확한 역할을 파악하기 위해서 발생 단계에 따른 에스트로겐 수용체의 수컷 생식기관 내 분포를 정리해 보고, 내분비계 교란물질의 노출에 따른 수컷 생식계의 발생 및 분화 이상과 정자형성과정의 장애 등을 알아보고자 하였다. 끝으로 외인성 화학물의 에스트로겐성을 평가하기 위한 지표인자들을 정리하여, 남성 생식기관의 발생, 분화, 기능에 관련된 에스트로겐의 역할에 대한 실제적인 정보를 얻을 수 있을 것으로 사료된다.

• The Korean Journal of Physiology and Pharmacology
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• 제18권3호
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• pp.191-200
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• 2014

We investigated the anxiolytic-like activity of ${\alpha}$-asarone (AAS) from Acorus gramineus in an experimental rat model of anxiety induced by repeated administration of the exogenous stress hormone corticosterone (CORT). The putative anxiolytic effect of AAS was studied in behavioral tests of anxiety, such as the elevated plus maze (EPM) test and the hole-board test (HBT) in rats. For 21 consecutive days, male rats received 50, 100, or 200 mg/kg AAS (i.p.) 30 min prior to a daily injection of CORT. Dysregulation of the HPA axis in response to the repeated CORT injections was confirmed by measuring serum levels of CORT and the expression of corticotrophin-releasing factor (CRF) in the hypothalamus. Daily AAS (200 mg/kg) administration increased open-arm exploration significantly in the EPM test, and it increased the duration of head dipping activity in the HBT. It also blocked the increase in tyrosine hydroxylase (TH) expression in the locus coeruleus (LC) and decreased mRNA expression of brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, in the hippocampus. These results indicated that the administration of AAS prior to high-dose exogenous CORT significantly improved anxiety-like behaviors, which are associated with modification of the central noradrenergic system and with BDNF function in rats. The current finding may improve understanding of the neurobiological mechanisms responsible for changes in emotions induced by repeated administration of high doses of CORT or by elevated levels of hormones associated with chronic stress. Thus, AAS did exhibit an anxiolytic-like effects in animal models of anxiety.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2005년도 제22차 정기총회 및 학술발표회
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• pp.31-43
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• 2005

Isoflavones are naturally occurring plant chemicals belonging to the 'phytoestrogen' class. The isoflavones are strikingly similar in chemical structure to natural estrogens. The phenolic ring is a key structural element of most compounds that bind to estrogen receptors. Dietary components that recently have received attention for their action as phytoestrogens are soy isoflavones. Soy products are the most significant dietary sources of isoflavones. Recently It is concerned clinical nutrition of isoflavone that is driven by reason of alternative sources of exogenous estrogen are constantly being needed. Estrogen therapy after the menopause offers protection from cardiovascular disease, reduces the extent of osteoporosis and relieves menopausal symptoms. Exogenous estrogen treatment is a fear of possible increased risk of developing breast cancer and because of side effects. Daily intake of soybean or soy food can affirmative effect to disease occurrence, that is based on mechanical investigation, experimental results of animals and human. Research into isoflavone is going on various field to relieve hormone - dependent disease such as cancer, menopausal symptom, cardiovascular disease and osteoporosis. Isoflavone is plenty in soybean meal, soy by-product, but only limited information is available on isoflavone efficacy into animal husbandry. Thus we conducted three experiments to investigate the effects of dietary isoflavone on productivities, antioxidative responses and bone metabolism in poultry. Dietary supplementation of isoflavone resulted in preventing the lipid oxidation of plasma and egg yolk. Dietary isoflavone improved bone development in egg-type growing chicks and broilers in terms of tibial strength. It was suggested that the proper use of feed additives such as isoflavone might provide means of improving antioxidative effect, skeletal strength, egg and eggshell quality.

• Biomolecules & Therapeutics
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• 제21권4호
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• pp.313-322
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• 2013

Previous studies have demonstrated that repeated administration of the exogenous stress hormone corticosterone (CORT) induces dysregulation in the hypothalamic-pituitary-adrenal (HPA) axis and results in depression and anxiety. The current study sought to verify the impact of catechin (CTN) administration on chronic CORT-induced behavioral alterations using the forced swimming test (FST) and the elevated plus maze (EPM) test. Additionally, the effects of CTN on central noradrenergic systems were examined by observing changes in neuronal tyrosine hydroxylase (TH) immunoreactivity in rat brains. Male rats received 10, 20, or 40 mg/kg CTN (i.p.) 1 h prior to a daily injection of CORT for 21 consecutive days. The activation of the HPA axis in response to the repeated CORT injections was confirmed by measuring serum levels of CORT and the expression of corticotrophin-releasing factor (CRF) in the hypothalamus. Daily CTN administration significantly decreased immobility in the FST, increased open-arm exploration in the EPM test, and significantly blocked increases of TH expression in the locus coeruleus (LC). It also significantly enhanced the total number of line crossing in the open-field test (OFT), while individual differences in locomotor activities between experimental groups were not observed in the OFT. Taken together, these findings indicate that the administration of CTN prior to high-dose exogenous CORT significantly improves helpless behaviors, possibly by modulating the central noradrenergic system in rats. Therefore, CTN may be a useful agent for the treatment or alleviation of the complex symptoms associated with depression and anxiety disorders.

• 대한소아치과학회지
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• 제36권1호
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• pp.139-144
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• 2009

Growth hormone insensitivity(GHI) 증후군은 Laron에 의해 처음 보고된 질환으로 성장 호르몬 결핍증과 유사하게 악악면 양상과 심각한 성장 지연을 보이지만, 이와는 달리 혈중 성장호르몬은 정상이거나 증가되어 있고 혈중 Insulin like growth factor-I(IGF-I)과 성장 호르몬 결합 단백질은 감소되어 있는 특징을 보인다. 이 중에서 원발성으로 GHI 증후군을 보이는 경우를 라론 증후군으로 분류하고 있으며, 세계적으로 약 200여 증례가 보고되고 있으나, 치의학적인 보고는 극히드물다. 본 증례는 라론 증후군을 보이는 두 증례를 관찰한 바 작은 두개저와 상하악골, 왜소치, 구근상 치관, 침상 치근 등의 치아형태 이상 등의 다양한 구강 악안면 이상을 보였기에 이를 보고하는 바이다.