• Biomolecules & Therapeutics
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• v.8 no.2
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• pp.113-118
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• 2000

TEA, glibenclamide, L-NAME and SKF 525A-induced reversible contraction were investigated using acetylcholine, sodium nitroprusside (SNP) and pinacidil in rat abdominal and thoracic aorta. Acetylcho-line, SNP or pinacidil produced in a dose dependent manner relaxation on phenylephrine-induced contraction In rat aorta. TEA, SKF 525A, and L-NAME produced reversible contractions on acetylcholine-induced relaxation, but not on SNP- or pinacidil-induced relaxation. Glibenclamide significantly produced reversible con- traction on pinacidll-induced relaxation. The reversible effect of TEA on the acetylcholine-induced relaxation was reduced by SKF 525A. These results indicate that the acetylcholine-induced relaxation may be mediated by NO, cytochrome P$_{450}$-dependent epoxygenase pathway, or $Ca^{2+}$ activated $K^{+}$ channel, and the pinacidil-induced relaxation may be mediated by ATP-sensitive $K^{+}$ channel.annel.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.159-159
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• 1993

개의 관상동맥평활근세포를 이용하여 $K^{＋}$channel openers인 cromakalim과 pinacidil의 이완반응을 관찰하고, 이러한 이완반응의 세포내 기전에 대하여 검토하고자 하였다. Collagenase로 소화시켜 구한 평활근 세포들은 frypan blue 배출 검사 및 전자현미경학적으로 검사시 건전하고 생존해 있었다. 분산평활근세포들은 phenylephrine(PE)의 용량에 의존하여 수축하였고, EC$_{50}$는 2.3$\times$$10^{－12}$M이었다. PE에 의한 수축반응은 $K^{＋}$channel openers인 cromakalim 및 pinacidil의 용량에 의존하여 억제되었고 이때의 EC$_{50}$치는 각각 1,2$\times$$10^{－10}$M 및 6.B$\times$$10^{－10}$M이었다. 비교실험으로서 근절편의 장력을 측정하여 수축을 검정한 실험에서는 cromakalim의 이완반응의 ECEC$_{50}$치는 1.94$\times$$10^{－7}$ M로 근세포실험에 비하여 감수성이 훨씬 약하였다.훨씬 약하였다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.44-44
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• 1993

Rat 기관 평활근에서 GS 283은 Carbachol에 의한 수축을 용량 의존적으로 억제시켰으며 특히 $Ca^{2＋}$-free 용액에서 G5 283은 농도에 비례하여 $Ca^{2＋}$에 의한 수축을 억제 시켰으며, 전형적인 $Ca^{2＋}$ 길항제인 Verapamil도 유사한 효과를 나타내었으나 GS 283보다 강력하였다. GS 283은 칼슘 길항 효과 이외에도 약하지만 Antihistamine 및 Antimuscarine작용도 가지고 있는 것으로 나타났다. 한편 Rat 대동맥에서 GS 389는 Phenylephrine(PE)에 의한 수축을 용량 의존적으로 억제시켰으며 $Ca^{2＋}$-free 용액에서 PE에 의한 수축과 KCI에 의한 수축율 모두 억제시켰다. 이러한 결과는 GS283과 GS 389는 $Ca^{2＋}$에 길항적용이 있음을 암시하며 특히 수용체를 통한 $Ca^{2＋}$-channel과 세포막의 voltage를 통한 $Ca^{2＋}$-channel을 모두 억제함을 강력히 시사한다. 향후 in vivo model에 대한 이들 약물의 효과를 연구해 보아야 할 것으로 생각하며 이러한 효과가 직접 $Ca^{2＋}$-channel에 대한 작용인지 또는 GS화합물이 cyclic nucleotide를 증가시키는 효과가 있어서 이로 인한 2차적 작용인지를 더욱 밝혀야 할것으로 생각된다.

• The Korean Journal of Zoology
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• v.34 no.1
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• pp.8-19
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• 1991

Atrial natriuretic peptide(ANP)의 유리기전에 대한 특성을 알아보고자, 흰쥐의 적출심장 관류모형을 사용하여 연구한 바 다음과 같은 결과를 얻었다. 1. 심방을 확장시켰을 때 ANP의 유리는 촉진되었다. 그러나 과용량을 부하하면 확장기간보다 회복기간에 ANP의 유리가 현저하게 증가하였다. 2. Epinephrine과 phenylephrine을 주입하면 ANP의 유리 량이 증가했으나, isoproterenol을 주입하면 심박수와 우심방 내압이 현저하게 증가했는데도 ANP의 유리량은 오히려 감소하였다 3. 미주신경을 자극하면 심박수의 현저한 감소에도 불구하고 ANP의 유리량은 증가하였다. 이상과 같은 결과에서 볼 때 결론적으로, 심방의 용량부하에 의해 심방근의 신장수용체가 자극을 받아 ANP의 유리가 촉진되는 것은 분명하고, 심방근이 확장할 때 보다는 확장 후 다시 원래의 길이로 환원될 때 ANP가 유리될 것으로 사료된다. 그리고 ANP의 유리에 대한 adrenergic조절은 o-receptor가 관련되어 있으며 심박수와 심방내압이 ANP의 유리를 변화시키는 데는 반드시 필수적인 인자가 아닌 것으로 여겨진다. 또한 특히 미주신경의 자극으로도 ANP의 유리가 조절될 수 있다는 것이 본 연구를 통해 새로이 발견되었다.

• YAKHAK HOEJI
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• v.35 no.6
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• pp.509-514
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• 1991

The effect of diacylglycerol on glucose release was studied by using 1,2-dioctanoyl-sn-glycerol ($diC_8$), a cell permeable diacylglycerol, in perfused rat liver. The glucose release was increased by $diC_8(50\;{\mu}M$), and the effect was depended on calcium ions. The increment of glucose release by $diC_8(50\;{\mu}M$) was inhibited by indomethacin ($50\;{\mu}M$); the amount of glucose release was almost the same with that of control group. Arachidonic acid($200\;{\mu}M$) also increased glucose release and the release was inhibited by indomethacin. There was no synergistic effect on glucose release by the combination of $diC_8(50\;{\mu}M$) and phenylephrine($10\;{\mu}M$).

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.691-697
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• 1999

The pharmacological effects of hydrocooked(110oC, 5 hours) extracts of Bastard halibut have been investigated. All of the hydrocooked extracts showed the measurable contractile effect on the isolated rat duodenum and decreased the normal blood pressure in anesthetized rat. The hydrocooked extracts also exhibited a dose dependent relaxation on the isolated rat aorta precontracted with phenylephrine. Only RM 60 fraction of these extracts had the cytotoxic effect against MCF7 cell(human breast adenocarcinoma cell line), but the other fractions showed neither antibacterial activity nor antitumor activity. Although fish extracts fed group of rat maintained their original body weight, there were no notable changes in the hematological parameters, except that the levels of high density lipoprotein was significantly increased. These results suggest that the hydrocooked extracts of bastard halibut may contain a variety of bioactive materials.

• Journal of Dental Anesthesia and Pain Medicine
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• v.20 no.3
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• pp.173-178
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• 2020

We experienced a case of induction of general anesthesia without using neuromuscular blocking agents (NMBAs) in a 40-year-old woman with a history of anaphylaxis immediately after the administration of anesthetics lidocaine, propofol, and rocuronium to perform endoscopic sinus surgery 2 years before. The skin test showed a positive reaction to rocuronium and cis-atracurium. We induced general anesthesia without using NMBAs after inducing airway anesthesia with lidocaine (transtracheal injection and superior laryngeal nerve block). Deep general anesthesia was maintained with end-tidal 4 vol% sevoflurane. Hypotension was treated with phenylephrine infusion. The operation condition was excellent, and patient recovered without complications after surgery. Airway anesthesia with local anesthetics may be helpful when we cannot use NMBAs for any reason, including hypersensitivity to NMBA and surgery that needs neuromuscular monitoring.

• Biomolecules & Therapeutics
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• v.9 no.2
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• pp.119-124
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• 2001

In order to determine the role of dehydroepiandrosterone (DHEA), the important sex-steroid hormone precursor, in vascular reactivity in rats, animals were treated for two weeks with DHEA or sex hormones, and the vascorelaxant and contractile responses of isolated aorta were examined. DHEA diminished the acetylcholine (ACh)-induced relaxation in female rats, while the drug was without effect in males. Testoterone lowered the vasorelaxant activity to ACh in either sex. 17$\beta$-Estradiol enhanced ACh-induced vasorelaxation in male rats, but this female sex hormone did not influence in females. In male rats, the androgen receptor antagonist flutamide also enhanced vasorelaxant action of ACh. When the male rat aorta was incubated in vitro with a nitric oxide (NO) synthase inhibitor L-NAME, phenylephrine-induced contraction was greatly potentiated in DHEA-pretreated rats compared to control ones. The present results suggest that DHEA stimulates mainly androgen in female, but both androgen and estrogen in male rats. The participation of NO In the modulation of vascular reactivity with pretreated DHEA was also considered.

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.27-27
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• 1997

The effects of $a_1$-adrenoceptor stimulation on intracellular $Ca^{2+}$ ([C $a^{2+}$]$_{i}$ ) transient, contraction, and L-type $Ca^{2＋}$ current ( $I_{Ca,L}$) were studied in single cells isolated from ventricles of guinea pig hearts. Phenylephrine, $\alpha$$_1$-adrenergic agonist, (5$\times$10$^{-5}$ ~10$^{-4}$ M) produced a biphasic pattern of inotropism： transient negative response (decrease in contraction by 23.9$\pm$2.5% of control) followed by a sustained positive response (increase in contraction by 60.0$\pm$3.4%, mean $\pm$ SD, n=12).(omitted)ted)

• Proceedings of the Korean Biophysical Society Conference
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• 1997.07a
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• pp.28-28
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• 1997

Stimulation of $\alpha$$_1$-adrenergic receptor ($\alpha$$_1$-AR) by phenylephrine produced a decrease in intracellular N $a^{＋}$ activity ( $a_{Na}$ $^{i}$ ) in multicellular preparations of cardiac tissues. The role of protein kinase C (PKC) in $\alpha$$_1$-adrenergic regulation of $a_{Na}$ $^{i}$ was studied in single ventricular myocyte isolated from guinea pig hearts. $a_{Na}$ $^{i}$ and membrane potential were measured with N $a^{+}$ indicator, sodium-binding benzofuran isophthalate tetraacetoxy methyl ester (SBFI/AM) and microelectrodes respectively when ventricular myocyte was stimulated at 0.3 Hz.(omitted)d)