• Bulletin of the Korean Chemical Society
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• 제24권10호
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• pp.1512-1514
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• 2003

• 대한한의학회지
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• 제24권4호
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• pp.87-91
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• 2003

Objectives: To examine the relaxational response to the water extract of Rheum palmatum L. and Rheum undulatum L. on rat thoracic aorta and abdominal aorta. Methods: Segments of thoracic aorta and abdominal aorta obtained from rats immediately after delivery were mounted in organ baths superfused on a polygraph. Results : We found that the thoracic aorta segments responded to the water extract of genus Rheum with a dose-dependent vasorelaxation. At $10^{-4}$ M 5-HT, the maximal contraction force was 93.5% of the maximum KCI-response. The 5-HT induced contractions at $10^{-4}$ M were inhibited by 86.4% and 62.1 % after addition of the high concentrations of R. palmatum root (RPR) and leaf (RPL) and R. undulatum root (RUR) and leaf (RUL). At 10 mg/ml RPR and RUR, the relaxational response at thoracic aorta and abdominal aorta with and without endothelium were 86.4%, 83.2%, 85.8%, and 62.1% of the maximum 5-HT induced contraction. Conclusion: Our result showed that RPL and RUL induced dose-dependent vasorelaxation on rat thoracic aorta and abdominal aorta, and that RPL and RUL roots have more potent effects than the leaves.

• The Korean Journal of Physiology and Pharmacology
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• 제1권5호
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• pp.547-553
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• 1997

It has been known that activation of tyrosine kinases is involved in signal transduction. Role of the tyrosine kinase in vascular smooth muscle contraction was examined in deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Male Sprague-Dawley rats underwent uninephrectomy, one week after which they were subcutaneously implanted with DOCA (200 mg/kg) and supplied with 1% NaCl and 0.2% KCl drinking water for $4{\sim}6$ weeks. Control rats were treated the same except for that no DOCA was implanted. Helical strips of carotid arteries were mounted in organ baths for measurement of isometric force development. Genistein was used as a tyrosine kinase inhibitor. Concentration-response curves to 5-hydroxytryptamine (5-HT) shifted to the right by genistein in both DOCA-salt hypertensive and control rats. Although the sensitivity to genistein was similar between the two groups, the maximum force generation by 5-HT was less inhibited by genistein in arteries from DOCA-salt hypertensive rats than in those from controls. Genistein-induced relaxations were attenuated in arteries from DOCA-salt rats. Genistein affected the contraction to phorbol 12, 13-dibutyrate (PDBu) neither in DOCA-salt nor in control arteries. These observations suggest that tyrosine kinase is involved in 5-HT-induced vascular contraction, of which role is reduced in DOCA-salt hypertension.

• 대한약리학회지
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• 제31권2호
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• pp.153-164
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• 1995

Sympathomimetic amines, especially ephedrine, are a major ingredient in proprietary medications for symptomatic treatment of upper respiratory infections. Their frequent uses can lead to occasional instances of abuse and habituation. The clinical symptoms of ephedrine abuse are similar to that of amphetamine psychosis and resemble closely that of schizophrenia. Because both amphetamine psychosis and schizophrenia are thought to be mediated primarily through the action on catecholamines, ephedrine-induced changes of the biogenic amines can be suspected. However, there were few studies about the central effects of ephedrine because of the milder central action than peripheral. Therefore, the present investigation was undertaken to elucidate the relations between the effects of single or repeated administration of ephedrine on the regional levels of biogenic amines in rat brain and ephedrine-induced CNS stimulation. The male Sprague-Dawley rats weighing $100{\sim}200\;g$ were used. After single or repeated administrations of ephedrine, blocks of tissue were obtained from frontal cortex, corpus striatum, hippocampus, thalamus, hypothalamus, substantia nigra and cerebellum. The concentration of biogenic amines(norepinephrine, epinephrine, dopamine, 5-hydroxytryptamine(5-HT)) and their metabolites (3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid(HVA), 5-hydroxyindoleacetic acid(5-HIAA)) were measured by means of high performance liquid chromatography-electrochemical detector(HPLC-ECD). The results obtained were as follows: 1) In the normal rat, the concentration of norepinephrine was the highest in hypothalamus. Dopamine, DOPAC and HVA were highest in corpus striatum, and 5-HT and 5-HIAA were highest in substantia nigra. Epinephrine was not detectable in any part of the brain tissue. 2) In a single administration of ephedrine, the concentration of DOPAC was decreased in corpus striatum. However, the other biogenic amines and their metabolites were not changed. 3) In repeated administration of ephedrine, the concentration of norepinephrine was decreased in all brain region checked. Dopamine was decreased in corpus striatum and substantia nigra and, increased in hypothalamus, and HVA was decreased in corpus striatum. 5-HT was decreased in all brain region except cerebellum and, 5-HIAA was decreased only in frontal cortex. The ratio of 5-HIAA/5-HT was increased in corpus striatum, thalamus, hypothalamus and substantia nigra. These data indicated that, although a single administration of ephedrine did not change the central neurotransmitters, repeated administration of ephedrine caused the decreases of norepinephrine and 5-HT in the most regions of brain, which may be responsible for the emergence of abnormal behavioral effect after ephedrine abuse.

• The Korean Journal of Physiology and Pharmacology
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• 제21권4호
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• pp.385-395
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• 2017

Vasoconstrictive properties of sympathomimetic drugs are the basis of their widespread use as decongestants and possible source of adverse responses. Insufficiently substantiated practice of combining decongestants in some marketed preparations, such are those containing phenylephrine and lerimazoline, may affect the overall contractile activity, and thus their therapeutic utility. This study aimed to examine the interaction between lerimazoline and phenylephrine in isolated rat aortic rings, and also to assess the substrate of the obtained lerimazoline-induced attenuation of phenylephrine contraction. Namely, while lower concentrations of lerimazoline ($10^{-6}M$ and especially $10^{-7}M$) expectedly tended to potentiate the phenylephrine-induced contractions, lerimazoline in higher concentrations ($10^{-4}M$ and above) unexpectedly and profoundly depleted the phenylephrine concentration-response curve. Suppression of NO with NO synthase (NOS) inhibitor $N^w$-nitro-L-arginine methyl ester (L-NAME; $10^{-4}M$) or NO scavanger $OHB_{12}$ ($10^{-3}M$), as well as non-specific inhibition of $K^+$-channels with tetraethylammonium (TEA; $10^{-3}M$), have reversed lerimazoline-induced relaxation of phenylephrine contractions, while cyclooxygenase inhibitor indomethacin ($10^{-5}M$) did not affect the interaction between two vasoconstrictors. At the receptor level, non-selective 5-HT receptor antagonist methiothepin reversed the attenuating effect of lerimazoline on phenylephrine contraction when applied at $3{\times}10^{-7}$ and $10^{-6}M$, but not at the highest concentration ($10^{-4}M$). Neither the 5-$HT_{1D}$-receptor selective antagonist BRL 15572 ($10^{-6}M$) nor 5-$HT_7$ receptor selective antagonist SB 269970 ($10^{-6}M$) affected the lerimazoline-induced attenuation of phenylephrine activity. The mechanism of lerimazoline-induced suppression of phenylephrine contractions may involve potentiation of activity of NO and $K^+$-channels and activation of some methiothepin-sensitive receptors, possibly of the 5-$HT_{2B}$ subtype.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.65-65
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• 2003

Serotonin(5-hydroxytriptamine, 5-HT)은 biogenic amlne류 신경전달물질로써, 다양한 생리조절활성을 갖고있다. 생식과 관련된 5-HT 기능으로 최근 사정 기능의 조절 가능성이 제시되었는데, 항우울제로 흔히 사용되는 selective serotonin reuptake inhibitor(SSRI) 계 약물을 장기 투여할 때 Premature ejaculation이 개선된다는 임상적인 증거들이 보고되었다. 본 연구는 수컷 흰쥐를 사용하여 생식기관, 특히 사정과 관계되는 기관들에서의 5-HT 수용체 아형들의 유전자 발현 여부와 그 조절 기작을 조사하였다. 흰쥐 수컷의 생식장기들인 고환, 부정소, 정관, 정낭에서 사정현상에 관여하리라 추정되는 세로토닌 수용체 아형들(type 1A, 1B, 2C)의 유전자 발현을 RT-PCR과 Southern blot으로 확인하였다. SSRI(sertraline)을 흰쥐에 매일 투여하는 모델(25mg/개체, 2주간)에서 1A 아형의 발현의 경우 정낭에서는 감소하였으나 정관에서는 증가하였고, 1B 아형의 발현은 두 장기에서 공히 증가하였다. 고환 제거후 testosterone(T) 보충 실험 모델을 사용한 실험에서, 정낭에서의 1A와 1B 발현은 T 보충에 의해 감소하였고, 정관에서는 큰 변화가 없었다. 한편 고환, 정낭과 정관에서의 세로토닌 수용체 아형 1A와 1B의 발현은 사춘기의 개시와 함께 증가하였다가 이후 점차 감소하는 경향을 보였다. 본 연구 결과는 사정 현상에 있어서 말초성 세로토닌 시스템이 중요한 역할을 담당할 가능성을 시사하는 것으로써, (i) 고등 포유동물에서의 사정 기작의 조절에 대한 과학적인 이해를 증진시키고, (ⅱ) 세로토닌 수용체 아형간의 특이한 발현과 작용에 대한 이해를 통해 보다 효과적인 사정 부전 치료법 개발을 시도할 수있고, (ⅲ) ontogeny와 sex steroid 의존성에 관련된 연구 시도는 노화와 관련된 사정능력의 변화와 같은 남성과학 분야로의 접목을 기할 수 있다고 사료된다.

• The Korean Journal of Physiology and Pharmacology
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• 제11권3호
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• pp.113-119
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• 2007

Developmental disability shows life-long behavioral abnormality with no significant physical malformation. This study was undertaken to develop an animal model for developmental disability by using two-factor approach. Lipopolysaccharide (LPS), a bacterial toxin, and NAN-190, a $5-HT_{1A}$ receptor antagonist, were administered to Sprague-Dawley rats on postnatal day (PND) 5 to induce inflammation and an altered 5-HT system, respectively. Long-term alteration of behavior occurred in the drug-treated groups. The LPS-treated group showed impaired motor coordination in the Rota-rod test. The LPS- treated or both LPS and NAN-190-treated groups showed impaired fore-paw muscle power in the wire maneuver test. These groups also showed decreased white matter volume and increased serotonergic fibers. The LPS and NAN-190-treated group also exhibited neurologic deficit in the placing reaction test and impaired equilibrium function in the tilt table test. The results showed that a variety of altered behaviors can be generated by two factor model, and suggested that combination of important etiologic factors and possible underlying defects is a promising strategy of establishing an animal model for developmental disabilities.

• Korean Journal of Acupuncture
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• 제30권1호
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• pp.37-46
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• 2013

Objectives : The Meridians and acupuncture points are the fundamental theories for acupuncture therapy. They have been associated with nervous system, but It is not well defined. We investigated that the effects of acupuncture at the river points(LU8, HT4, PC5, SP5, KI7, LR4) on the changes in the expression of nNOS, iNOS, eNOS, and NE in rats. Methods : The Male Sprague-Dawley rats were divided into 6 groups each non-acupuncture and acupuncture group. We inserted needle and retained for 5 minutes on both left and right sides of LU8, HT4, PC5, SP5, KI7, LR4 which were the river points of five transport points for 6 yin meridian vessels. After that, blood was drawn via cardiac puncture, and tissues for each point near meridian vessels were extracted to examine the changes in the changes of nNOS, eNOS, iNOS and NE. Results : The LU8 and HT4 group showed a significant decrease on nNOS. In terms of eNOS and iNOS, the LU8 group decreased significantly while the KI7 group increased significantly. However, the experimental groups didn't show any significant changes on the plasma and tissue norepinephrine without plama NE in SP5 group. Conclusions : The effect on the nNOS, iNOS, eNOS of acupuncture at LU8 and KI7 could be observed, and it is considered that the effect of acupuncture related with on nervous system could be studied by additional researches based on this one.

• Journal of Acupuncture Research
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• 제18권1호
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• pp.202-216
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• 2001

Subject : After acupuncture at So-Chung(HT9) in humans(n=4) we intend to know the differents of acupuncture at acupuncture and non-acupuncture on the electrical frequency change and signal transmission along the meridian with different acupuncture manipulation method. Met6ods : The etectrical signal on the heart merdian acupuncture point, So-Bu(HT8), Shin-Moon(HT7) and So-Hae(HT3), and control non acupuncture points was measured by electrodes biopack instrument. Acupuncture needles(diameter: 0.25mm, length:30mm) were used for acupuncture. The frequency was recorded before, during and after needling the So-chung. Results : After acupuncture the components between 2 and 5Hz frequency level were decreased comparing with that of pre-acupuncture state. Time-delayed correlation coefficient was increased every 10 seconds. It imply that the signal may be transferred. These effects did not appear at non acupuncture point and also did not arise when there was no ki(氣) feeling. These results suggest that acupuncture stimulation is similar to 2~5Hz frequency electric acupuncture. and ki feeling and manipulation which can induce ki feeling is very important in acupuncture clinic.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6403-6407
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• 2012

Detoxifying enzymes are present in most epithelial cells of the human gastrointestinal tract where they protect against xenobiotics which may cause cancer. Induction of examples such as glutathione S-transferase (GST) and its thiol conjugate, glutathione (GSH) as well as NAD(P)H: quinoneoxidoreductase (NQO1) facilitate the excretion of carcinogens and thus preventing colon carcinogenesis. Pterostilbene, an analogue of resveratrol, has demonstrated numerous pharmacological activities linked with chemoprevention. This study was conducted to investigate the potential of pterostilbene as a chemopreventive agent using the HT-29 colon cancer cell line to study the modulation of GST and NQO1 activities as well as the GSH level. Initially, our group, established the optimum dose of 24 hours pterostilbene treatment using MTT assays. Then, effects of pterostilbene ($0-50{\mu}M$) on GST and NQO1 activity and GSH levels were determined using GST, NQO1 and Ellman assays, respectively. MTT assay of pterostilbene ($0-100{\mu}M$) showed no cytotoxicity toward the HT-29 cell line. Treatment increased GST activity in the cell line significantly (p<0.05) at 12.5 and $25.0{\mu}M$. In addition, treatment at $50{\mu}M$ increased the GSH level significantly (p<0.05). Pterostilbene also enhanced NQO1 activity significantly (p<0.05) at $12.5{\mu}M$ and $50{\mu}M$. Hence, pterostilbene is a potential chemopreventive agent capable of modulation of detoxifiying enzyme levels in HT-29 cells.