• The Korean Journal of Mycology
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• v.20 no.3
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• pp.259-268
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• 1992

Fifty-three actinomycetes antagonistic to Phytophthora capsici and Magnaporthe grisea were isolated from rhizosphere soils in six pepper-growing areas and ashore soils. Thirty-two antagonistic actinomycetes, showing inhibition zone larger than 5 mm, were classified into 20 groups according to their colony morphology and color. The antagonistic activity against P. capsici greatly varied, which showed inhibition zone sizes in the ranges from 5.7 to 17.5 mm on V-8 juice agar and from 2.5 to 17 mm on tryptic soy agar. The antagonistic activity of some actinomycetes tested was remarkably different between the two test media. The antagonists showed a relatively broad antifungal spectrum, but their antibacterial activity was negligible, except for Pseudomonas solanacearum. Butanol extracts of culture filtrates from antagonistic actinomycetes inhibited mycelial growth of P. capsici and M. grisea, thereby confirming strongly antibiotic production in culture. Culture filtrates of some antagonistic actinomycetes completely inhibited Phytophthora blight in pepper plants.

• Korean Journal of Veterinary Research
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• v.38 no.3
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• pp.525-534
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• 1998

신장 근위세뇨관세포들은 사구체에서 여과된 물질의 재흡수, 분비 및 대사에 관여하는 여러 호르몬들의 수용체들을 가지고 있다. 이들중에서 norepinephrine(NE)과 angiotensin II(ANG II)는 $Na^{+}/H^+$ 상호운반계를 조절함으로써 혈압조절에 관여하는 것으로 알려져 있으나 이들의 상호관계에 대해선 연구보고가 많지 않다. 본 연구는 초대배양한 토끼신장 근위세뇨관세포를 이용한 $Na^+$ uptake 실험을 통하여 NE이 어떠한 수용체를 통하여 $Na^{+}/H^+$ 상호운반계를 조절하는지 그리고 이러한 작용에 있어서 NE과 ANG II의 상호관계를 알아보고자 실시하였다. NE(>$10^{-9}M$)은 $Na^+$ uptake를 유의성 있게 증가시켰다($10^{-9}M$ NE : $27{\pm}4%$ increase vs. Control;p < 0.05). $\alpha$ 길항제(phentolamine, $10^{-10}M$)는 NE($10^{-9}M$)에 의해 유도된 $Na^+$ uptake를 유의성 있게 차단하였으나 (phentolamine+NE : $29{\pm}5%$ inhibition vs. NE ; p〈 0.05), ${\alpha}_1$ (pra-zosin, $10^{-10}M$) 및 ${\alpha}_2$ 길항제(yohimbine, $10^{-10}M$)는 부분적으로 차단하였다. ${\beta}$ 길항제(propra-nolol, $10^{-10}M$)도 역시 NE에 의해 유도된 $Na^+$ uptake를 유의성 있게 차단하였으나(propranolol+NE : $24{\pm}6%$ inhibition vs. NE ; p< 0.05), ${\beta}_1$(atenolol, $10^{-10}M$) 및 ${\beta}_2$ 길항제(butoxamine, $10^{-10}M$)는 부분적으로 차단하였다. 이러한 결과들은 NE에 의해 유도된 $Na^+$ uptake 증가작용은 ${\alpha}$(${\alpha}_1$ 및 ${\alpha}_2$ )와 ${\beta}$(${\beta}_1$ 및 ${\beta}_2$) 수용체 모두를 통하여 일어난다는 것을 시사해주고 있다. ANG II($10^{-11}M$) 또는 NE(${\alpha}_1$, ${\alpha}_2$, ${\beta}_1$, ${\beta}_2$ 작동제) 단독처리군의 $Na^+$ uptake는 대조군에 비해 유의성 있게 증가하였으나 (ANG II : $23{\pm}9%$ increase vs. Control; p < 0.05), 병합처리시 상승작용은 나타나지 않았다. ${\alpha}$ 또는 ${\beta}$ 길항제 처리시 NE 및 ANG II에 의해 유도되었던 $Na^+$ uptake 증가는 유의성 있게 차단되었다(phentolamine+NE+ANG II : $25{\pm}3%$ inhibition, propranolol+NE+ANG II : $24{\pm}6%$ inhibition vs. NE+ANG II, respectively ; p〈 0.05). 이 결과들은 $Na^+$ uptake에 있어서 ${\alpha}$(${\alpha}_1$ 및 ${\alpha}_2$)와 ${\beta}$(${\beta}_1$ 및 ${\beta}_2$) 수용체와 ANG II의 관련성을 시사해 준다. 결론적으로 토끼 신장 근위세뇨관세포에서 NE은 ${\alpha}_1$, ${\alpha}_2$, ${\beta}_1$ 및 ${\beta}_2$ 수용체를 통하여 $Na^+$+ uptake를 증가시켰으며 이들 수용체는 ANG II $Na^+$ uptake 증가작용에 관여하였다.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.382-395
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• 1992

GABA is an inhibitory neurotransmitter in central nervous system and produce sedative, antianxiety and muscle reaxing effects via $GABA_A$ receptor or $GABA_B$ receptor. Recently it is known that GABA is widely distributed throughout peripheral organs and may playa physiological role in certain organ. The vas deferens is innervated by species-difference. These study, therefore, was performed to investigate the mode and the mechanism of action of GABA on the norepiniphrine-, ATP- and electric stimulation-induced contraction of vas deferens of rat. Sprague-Dawley rats were sacrificed by cervical dislocation. The smooth muscle strips were isolated from the prostastic portion and were mounted in the isolated muscle bath. PSS in the bath was aerated with 95/5%-$O_2/CO_2$ at $33^{\circ}C$. Muscle tensions were measured by isometric tension transducer and were recorded by biological recording system. 1. GABA, muscimol, a $GAB_A$ agonist, and baclofen, a $GABA_B$ agonist inhibited the electric field stimulation(EFS, 0.2Hz, 1mSec, 80 V, monophasic square wave)-induced contraction with a rank order of potency of GABA greater than baclofen greater than muscimol. 2. The inhibitory effect of GABA was antagonized by delta aminovaleric acid(DAVA), a $GABA_B$ antagonist, but not by bicuculline, a $GABA_A$ mtagonist. 3. The inhibitory effect of baclofen was antagonized by DAVA, but the effect of muscimol was not antagonized by bicuculline. 4. Exogenous norepinephrine(NE) and ATP contracted muscle strip concentration dependently, but the effect of acetylcholine was negligible : and GABA did not affect the NE-and ATP-induced contractions. 5. GABA, baclofen and muscimol did not affect basal tone, and GABA did not affect the NE-and ATP-induced contractionsm 6. EFS-induced contraction was including 2 distinctable components. The first phasic component was inhibited by beta gamma-methylene ATP(mATP), a desensitizing agent of APT receptor and the second tonic component was reduced by pretreatment of reserpine(3 mg/Kg, IP). 7. GABA inhibited the EFS-induced contraction of reserpinized strips, but not the mATP-treated strips. These results suggest that in the prostatic portion of the rat vas deferens, adrenergic and purinergic neurotransmissions are exist, and GABA inhibits the release of ATP via presynaptic $GABA_B$ receptor on the excitatory neurons.

• Journal of Mushroom
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• v.2 no.4
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• pp.184-191
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• 2004

Mutual growth limitation was observation when the two antagonistic fungi was come in contact with each other. Brown line was formed 2day after contact with Trichoderma spp., and then, green spores formed overnight. The laccase activity of L. edodes was stimulated when this fungus wsa co-incubated with Trichoderma spp. for a few days in liquid media. In sawdust-rice bran nixtures, outstanding broun line developed when the two antagonistic fungi co-cultured. The pH of the substrates changed from 5.5 to 4.5 after overgrowth, suggesting a difference in the degradation ability and the preference of the two fungi for the lignocellulose material.

• The Korean Journal of Pharmacology
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• v.23 no.1
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• pp.33-44
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• 1987

NADPH oxidase dependent superoxide generation and phagocytosis in neutrophils stimulated with opsonized zymosan or heat aggregated IgG were coincided with the process of calcium uptake. The responses in activated neutrophils were enhanced with increasing concentrations of extracellular calcium and these effects were significantly inhibited by calcium chelators, EGTA and EDTA. The superoxide generation in activated neutrophils was reduced by dantrolene and chlorpromazine. Calcium antagonists, bepredil, diltiazem, verapamil, nifedipine and nimodipine effectively inhibited the calcium uptake, superoxide generation and phagocytosis in activated neutrophils, and NADPH oxidase activity was also inhibited. The results suggest that calcium antagonists may inhibit the superoxide generation and phagocytosis in activted neurtophils by the inhibition of calcium influx and by the action on intracellular redistribution of calcium and NADPH oxidase system.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.336-342
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• 2010

The purpose of this study was to determine the antagonistic effects of flumazenil on anesthesia induced with tiletamine/zolazepam in dogs. The anesthetic effects (sedation, analgesic, muscle relaxation, posture and auditory response score), vital signs (heart rate, respiratory rate and rectal temperature) and blood biochemistry (glucose (GLU), total protein (TP), alanine aminotransferase (ALT), aspartate aminotransferase (AST)) were examined as indicators of the antagonistic effects. A total of 6 clinically healthy mongrel dogs were used in this study. The dogs in TZ group received administration of tiletamine/zolazepam 10 mg/kg IV. The dogs in TZF group received administration dose of TZ 10 mg/ kg IV followed by the administration of flumazenil 0.1 mg/kg 20 minutes after administering a TZ 10 mg/kg dose. There were significant differences in the recovery of anesthesia between the groups. The GLU level in the TZF group after the administration of flumazenil was significantly higher than that of the TZ group. There was a larger change in the HR in the TZF group than in the TZ group until 30 minutes after flumazenil administration. The sternal recumbency, standing and walking times of the TZF group were faster than those of the TZ group. In conclusion, flumazenil showed antagonistic effect against tiletamine/zolazepam in dogs. When recovering from anesthesia, flumazenil reduced sternal recumbency, standing and walking times.

• The Korean Journal of Pharmacology
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• v.20 no.2
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• pp.7-14
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• 1984

In pithed rats, rising in diastolic blood pressure by clonidine, when intravenously injected, is expressed as the postsynaptic action, and inhibitory action on electrical stimulation-induced tachycardia by clonidine is expressed as the presynaptic inhibitory action. In this study it was aimed to observe the inhibitory effect of imipramine caused by a single and chronic administration on both postsynaptic and presynaptic action of clonidine in pithed rats, and discussed in relation with the mechanism of antidepressant action of imipramine. 1) A rise of diastolic blood pressure by clonidine was not antagonized by prazosin, but by both phentolamine and piperoxan. 2) The inhibition by clonidine of tachycardia which was induced by electrical stimulation was also antagonized by phentolamine and piperoxan, but not by prazosin. 3) The increase in diastolic blood pressure in response to clonidine was inhibited by both a single or chronic administration with imipramine (20 mg/kg). It was more pronounced in the latter. 4) The inhibitory action of clonidine on the tachycardia was markedly inhibited by both types of administration with imipramine, between which there showed little difference. It is concluded that the presynaptic ${\alpha}_2-adrenoceptor$ is rather sensitively affected by a single administration with imipramine, and a long-term imipramine treatment may inhibit both pre- and postsynaptic ${\alpha}_2-adrenoceptors$, simultaneously. Furthermore, it was seemed unlikely that these results provide the evidence :to support the fact that the subsensitivity of presynaptic ${\alpha}_2-adrenoceptor$ may be the mechanism of action of tricyclic antidepressant.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.126-128
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• 1998

토양의 완충능이 없는 양액재배에서 Ca 흡수는 양이온과의 길항작용, 온도, 습도 및 염류농도 등에 의해 변화된다. 배양액내 무기 양이온 중 Ca 과 K, Mg의 복합비율 조성에 따른 상추의 광합성, 기공저항, 수분이용효율 및 증산량을 측정하여 상추 tipburn에 관여하는 Ca 흡수를 알아보고자 본 실험을 수행하였다. (중략)

• Journal of Pharmaceutical Investigation
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• v.16 no.4
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• pp.135-138
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• 1986

Ginseng total saponins(GS), protopanaxadiol saponins(PD) and protopanaxadiol saponins(PT) antagonized the analgesia in mice induced by morphine. The administrations of 2,4-dihydroxyphenylalanine, and 5-hydroxytryptophan reduced the GS, PD and PT antagonisms of morphine analgesia. Possible mechanisms involved in the antagonistic actions of GS, PD and PT on morphine analgesia were described.

• YAKHAK HOEJI
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• v.37 no.6
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• pp.625-630
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• 1993

Among the six antihistamine agents tested in this study, homochlorcyclizine showed the highest bradykinin antagonistic activity in the receptor binding assay as well as the isolated rat ileum assay. Schild plot analysis of bradykinin-induced ileal contraction in the presence of three different concentrations of homochlorcyclizine revealed a pA$_{2}$=6.26, and a correlation coefficient of 0.984. Homochlorcyclizine of (100 $\mu{M}$ final concentration) also showed 25% antagonistic activity in the receptor binding assay.