• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.327-332
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• 1994

The effect of methylglyoxal-bis (guanylhydrazone) (MGBG) and ethylene synthesis inhibitors on adventitious root formation from soybean cotyledon in relation to ethylene production and endogenous polyamine content was investigated. Cotyledon explants cultured on rooting medium formed numerous adventitious rook on the cut surfaces after 2 weeks of culture. However when cultured on rooting medium supplemented with MGBG, the root formation was strongly inhibited, its inhibitory effect was reserved when cultured on medium with MGBG + spermine, MGBG + CoCl$_2$ and MGBG + spermine+CoC1$_2$. A slight reversion of the rooting inhibition was observed in 10$^{-3}$ M MGBG +10$^{-5}$ M spermine treatment, whereas it caused a significant effect in 10$^{-3}$ M MGBG +10$^{-4}$ M treatment .Ethylene production and endogenous polymine content was investgated in 10$^{-3}$ M MGBG , 10$^{-3}$ M MGBG +10$^{-5}$ Mspermine, 10$^{-3}$ M MGBG +10$^{-4}$ M CoCl$_2$and 10$^{-3}$ M MGBG +10$^{-5}$ M spermine +10$^{-4}$ M CoCl$_2$treatments. Ethylene production highest in 10$^{-3}$ M MGBG +10$^{-5}$ M spermine treatment was higher than control. In 10$^{-3}$ M MGBG +10$^{-5}$ M spermine + 10$^{-4}$ M CoCl$_2$ treatment, ethilene production was lowest, whereas polyamine level was highest.

• Journal of Plant Biology
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• v.34 no.1
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• pp.53-57
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• 1991

The effect of polyamines and methylglyoxal bis(guanylhydrazone)(MGBG) on the activity of diamine oxidase was studied in soybean (Glycine max) seedlings. $10^{-2}\;M$ of putrescine, spennidine, and spermine inhibited diamine oxidase activity, whereas $10^{-6}\;M$ putrescine increased enzyme activity. These results suggest that diamine oxidase can be induced by a specific substrate, putrescine. The content of putrescine was increased in response to the increase in concentratioin of MGBG. In vitro, 40% of the diamine oxidase activity was inhibited by $10^{-3}\;M$ MGBG. In vivo, the diamine oxidase activity was increased by a low concentrration of MGBG. It was suggested that MGBG inhibited the formation of spermidine and that the accumulated putrescine induced diamine oxidase, whereas the diamine oxidase acitivity was inhibited by a high concentration of MGBG. It is suggested that a high cocentration of MGBG increases the putrescine content by inhibiting diamine oxidase activity which is responsible for putrescine degradation.dation.

• Journal of Plant Biology
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• v.37 no.1
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• pp.101-109
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• 1994

Relationship between polyamine level and DNA methylation in the absence or presence of MGBG(l mM), which is an enzyme-activated reversible inhibitor of SAMDC, has been investigated during gametogenesis of Chlamydomonas. In the absence of MGBG, polyamine levels decreased in Chlamydomonas 137C(+) and 137C(-) during gametogenesis. And polyamine level of 137C(+) was 2-5 times as much as that of 137C(-) and showed a significant decrease unlike that of 137C(-). In vitro, MGBG inhibited ctDNA methylation of 137C(+) by 20-30% but did not inhibited that of 137C(-). Also, MGBG inhibited DNA methylase by 60% in vitro. The results obtained in the present work suggest the possibility that the changes of polyamine level may be associated with ctDNA methylation during gametogenesis of Chlamydomonas.omonas.

• Journal of Plant Biology
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• v.37 no.2
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• pp.195-201
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• 1994

In order to study the effects of polyamine inhibitors and polyamines on adventitious root formation, the correlation between adventitious root formation and carbohydrate metabolism was investigated in inoculated soybean (Glycine max L.) cotyledons at the concentration of $10^{-3}\;M$ methylglyoxal bis-(guanylhydrazone)[MGBG], and $10^{-3}\;M$ MGBG plus $10^{-5}\;M$ polyamines (putrescine, spermidine and spermine), respectively, for the adventitious root formation medium. The contents of starch, maltose and sucrose were lower in control and were higher in the treatments containing $10^{-3}\;M$ MGBG, and $10^{-3}\;M$ MGBG plus $10^{-5}\;M$ polyamines during culture. It was shown that the soluble sugar levels, except glucose, were higher than that of control in most of the treatments and the change in glucose contents tended to be similar to that control. The amylase activity increased in control and MGBG treatment, the maltase activity was higher in control and the invertase activity showed less substantial changes during culture.ulture.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.117-123
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• 2000

In order to study the role of polyamines on the formation of adventitious roots, trichomes and calli, the effects of putrescine, spermidine, spermine, cyclohexylamine (CHA) and methylglyoxal-bis(guanylhydrazone) (MGBG) were investigated in the leaf segment cultures from ecotype Columbia of Arabidopsis thaliana. When the leaf segments were cultured on the media for forming adventitious roots (0.1 mg/L NAA), trichomes (2.0 mg/L NAA) and calli (10.0 mg/L NAA), and then each cultures was treated with 1-100 mg/L of putrescine, spermidine and spermine, respectively. On the adventitious root-forming medium treated with polyamines the trichomes were induced with adventitious roots. And on the trichome-forming medium with polyamines calli were induced with trichomes. In orther hand each cultures was treated with 1-100 mg/L of CHA and MGBG, respectively. CHA promoted adventitious roots on the medium for adventitious roots, was not effected on media for trichomes and calli. MGBG inhibited adventitious roots, trichomes and calli in all cultures, and induced adventitious roots on medium for trichomes in high concentration.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.105-110
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• 1994

In order to study on the effect of polyamine inhibitors and polyamines on adventitious root formation the correlation between adventitious root formation and polyamine levels were investigated in cultured soybean (Glycine max L.) cotyledons. Adventitious root formation was inhibited in medium containing 10$^{-4}$ -10/ sup -2/ M polyamine inhibition such as $\alpha$-difluoromethylornithine (DFMO), $\alpha$-difluoromethylarginine (DFMA), cyclohexylammonium sulfate (CHA), dicyclohexyl-amine (DCHA) and methylglyoxal-bis (guanylhydrazone) (MGBG). An inhibitory effects at 10$^{-3}$ M MCBG were much higher than other treatments. Treatment with 10$^{-3}$ M MGBG plus 10$^{-5}$ M spermine led to reversal of the effects of MGBG alone. The polyamine levels were sharply increased in the first few days in each treatnent compared to control. The remarkably increasing polyamine contents were observed in medium supplemented spermine.

• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.113-123
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• 1996

It has been well known that polyamines ensure the stability of chromatin structure and the fidelity of DNA transcription. This study was carried out to evaluate the effect of polyamines on the apoptosis of mouse thymocytes induced by dexamethasone and polyamine synthesis inhibitors. 1) In the histological death findings of thymocytes double-stained with acridine orange and ethidium bromide, the apoptotic and the necrotic fractions (AF; NF) in the control group were $9.4{\pm}4.2%$ and $4.5{\pm}5.3%$, respectively. Dexamethasone $(3\;{\times}\;10^{-8}\;M:\;DX)$ in creased AF upto $52.0{\pm}8.1%$ and did not change NF, but A23187 $(5\;{\times}\;10^{-7}\;M:\;A2)$ increased AF and NF upto $45.0{\pm}8.9%$ and $20.5{\pm}10.6%$, respectively. 2) The thymocyte viability was significantly reduced by DX, DHEA $(1\;{\times}\;10^{-4}\;M)$, A2, DFMO $(1\;{\times}\;10^{-4}\;M)$, and $MGBG\;(1\;{\times}\;10^{-4}\;M)$, respectively. It was, however, little affected by $aminoguanidine\;(1\;{\times}\;10^{-4}\;M:\;AG)$, $putrescine\;(1\;{\times}\;10^{-5}\;M:\;PT)$, $spermidine\;(1\;{\times}\;10^{-5}\;M:\;SD)$, and $spermine\;(1\;{\times}\;10^{-5}\;M:\;SM)$. 3) The genomic DNA of mouse thymocyte was markedly fragmented by DX and A2, respectively, and to a lesser extent, by DHEA, but was little affected by MGBG, DFMO, AG, and each of polyamines. 4) The DX induced reduction of thymocyte viability was moderately attenuated by DHEA, but little affected by DFMO, MGBC, and AG. However, SM significantly attenuated the viability reduction induced by A2 as well as DX. 5) The thymocyte viability reduction by MGBG and DFMO was significantly attenuated by only SM among three polyamines applied in this study. 6) The thymocyte viability redution by combined treatments of DX with DFMO and MGBG, respectively, was significantly attenuated by SM, and moderately by PT. But the viability reduction by combined treatment of DX with AG or DHEA was not affected by polyamines. These results suggest that polyamines, particularly spermine, might play the inhibitory role in thymocyte apoptosis and the inhibitory effect can be ascribed in part to the increase of polyamine uptake by thymocytes pretreated with DFMO and MGBG.

• BMB Reports
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• v.28 no.3
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• pp.191-196
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• 1995

The role of polyamines in skeletal myoblast differentiation was investigated using the polyamine metabolic inhibitor methylglyoxal bis(guanylhydrazone)(MGBG). Concentrations of intracellular free spermidine and spermine increased 2 to 2.5-fold at the onset of myoblast fusion. The systhesis of actin, and creatine kinase activity both dramatically increased during myotube formation. However, MGBG at a concentration of 0.5 mM not only abolished the increase of intracellular free polyamines, but also reduced cell fusion to almost half the level of untreated cells, without noticeable morphological alteration. The production of actin, and creatine kinase activity were almost completely abolished by MGBG. The inhibition of myoblast fusion by MGBG was partially recovered with 0.1 mM of spermidine or spermine added externally. Results indicate that polyamines are necessary for normal myoblast differentiation. Since the first indication of myoblast differentiation is alignment of muscle cells and membrane fusion of adjacent cells, and since polyamine depletion completely inhibited the synthesis of actin, which might be associted with membranes, polyamine might be involved in myoblast differentiation through membrane reorganization events.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.323-334
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• 1996

Male Mongolian gerbils $(60{\sim}80g)$ were given DL-difluoromethylornithine (DFMO; 250mg/kg, ip) and methylglyoxal bis(guanylhydrazone) (MGBG; 50 mg/k, ip), respectively, 1 h prior to transient (7 min) occlusion of bilateral common carotid arteries (OBC7) and a daily dose of one of them for 6 days after recirculation, and the polyamine contents, activities of ornithine and S-adenosylmethionine decarboxylases (ODC and SAM-DC), and light microscopic findings of the hippocampus were evaluated. The hippocampal putrescine (PT) levels of the control gerbils treated with saline (STGr), markedly increased after OBC7, showing a peak level at 24 h after recirculation. The peak PT level was reduced in DFMO treated gerbils (DTCr) and in MGBG treated gerbils (MTGr). And 7 days after recirculation, the PT level of DTGr was decreased to about 75% of the PT level in the sham operated group (nonTGr) and to about 55% of the STGr level, respectively. The hippocampal spermidine (SD) level of STGr tended to decline, showing the lowest value at 8 h after recirculation. But the spermidine (SD) level of DTGr was somewhat higher at 8 h after OBC7 than those of STGr and MTGr The hippocampal spermine (SM) levels of all the experimental groups were little changed for 7 days after OBC. OBC7 markedly increased the hippocampal ODC activity. reaching a maximum (about 3 times higher than preischemic level) at 8 h and rapidly recovered to the control value by 24 h in STGr gerbils, and the OBC7-induced increase of ODC activity was significantly attenuated by DFMO or MGBG treatment. Whereas OBC7 induced a rapid decrease of the hippocampal SAMDC activity follwed by gradual recovery to the preischemic level, and the decrease of the SAMDC activity was slightly attenuated by DFMO or MGBG treatment. 7 Days after OBC7 the histological finding of the hippocampal complex stained with cresyl violet showed an extensive delayed neuronal damage in the CA1 region and to a lesser extent, in the dentate gyrus, sparing the CA3 region. And the neuronal death was aggevated by DFMO but significantly attenuated by MGBG. The immunochemical reactivity of hippocampus to anti-GFAP antibody was significantly increased in the CA1 region and to a lesser extent, in the dentate gyrus 7 days after OBC7, but was little changed in the CA3. And the increase of the anti-GFAP immunoreactivity was moderately enhanced by DFMO and significantly suppressed by MGBG. These results suggest that the polyamine metabolism may play a modulatory role in the ischemic brain damage.

• Journal of Korean Port Research
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• v.4 no.1
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• pp.33-43
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• 1990

우리나라에서는 70년대 이후 컨테이너 수송체계가 도입되어 운영되어 왔으나 차량의 급격한 증가와 더불어 컨테이너 수송체계는 도시교통에 있어서 많은 문제를 야기시키는 것으로 논란이 되고 있다. 특히, 부산항은 우리나라 최대의 국제 무역항으로써 전 컨테이너 수송화물의 90%이상을 처리하고 있고, 또한 수출입항으로서 제 역할을 다하고 있으나 낮은 도로율(12.45%)과 산재해 있는 30여개의 Off-Dock CY로 인해서 도심을 통과하는 컨테이너 수송차량은 많은 교통문제를 유발시키고 있다. 본 연구는 1) 부산시에 산재해 있는 30여개의 Off-Dock CY에 이르는 주요 도로상에서 컨테이너 수송량의 신간별 분포에 따라 컨테이너의 운행시간대를 첨두 시간대, 비첨두 시간대 및 심야 시간대로 분류하여 각 시간대별 평균 수송 시간 및 교통 체증으로 인한 수송 지체수준을 확인하였고, 2) 컨테이너 전용부두로 부터 Off-Dock CY에 이르는 도시 고속도로 및 주요간선도로상에서의 수송시간 및 수송 지체수준을 비교 분석하였으며, 3) 마지막으로, 효율적인 컨테이너 수송체계를 위한 최적 수송시간대 및 도로체계를 제시할 수 있었다. 특히, 컨테이너 수송시간 및 지체수준은 각 운행 시간대에 따라 현저한 차이를 보이고 있었는데, 심야 시간대를 이용하여 컨테이너 수송을 할 경우에는 다른 시간대에 비하여 50%정도의 수송시간 절감효과를 기대할 수 있었으며, 도시 고속도로를 이용할 경우에는 도시 간선도로에 비하여 30%정도의 수송시간을 절약할 수 있었다. 따라서 도시지역의 교통체중을 완화시키기 위해서 심야 시간대에 보다 많은 컨테이너 수송차량이 이용할 수 있는 컨테이너 수송체계가 확립되어야 하고, 산재해 있는 Off-Dock CY를 몇개의 ODCY그룹이나 단지까지 컨테이너 전용 고속도로의 건설이 바람직하고 생각된다.리구에서 조사한 결과 $10^{-3}$ M MGBG 단독 처리구에서 에틸렌 생성량이 가장 높았으며, spermidine과 spermine의 함량은 가장 낮았다. 부정근 형성능이 다소 회복된 $10^{-3}$ M MGBG+ $10^{-5}$M spermine 혼합처리구에서의 에틸렌 생성량은 대조구보다는 다소 높게 나타났다. 부정근 회복능이 가장 높았던 $10^{-3}$ M MGBG+ $10^{-5}$ M spermine + $10^{-4}$ M Cocl$_2$ 혼합처리구에서 에틸렌 생성량은 가장 낮게 나타났으며, polyamine 함량은 가장 높게 나타났다.(Cyperaceae), 명아주과(Chenopodiaceae) 같은 풀들이 하구언(estuary)의 해안가에 주로 서식하였던 것으로 나타났다. 이 시기동안에 해양성조류인 와편모류와 담수성 조류가 동시에 다양하게 산출되는 것은 하구언 퇴적환경이었음을 잘 지시해 준다. 제II화분대(고도, 43.72{\sim}3.36\;m$)가 시작되면서 혼합림은 침엽수림으로 바뀌었으며, 낙엽활엽수들의 서식지가 2엽소나무로 대치되면서 침엽수가 주요 수종을 이루었던 것으로 나타났다. 아마도 이런 산림형태는 자연 기후환경변화 뿐만 아니라 인간간섭에 의해 나타난 결과로 생각된다. 이 시기에 경작식물인 벼과(Gramineae), 옥수수(Zea), 메밀(Fagopyrum)과 논밭의 뚝 등지 에서 서식하는 돼지풀(Ambrosia) 등이 처음으로 산출되는 것으로 보아 인간간섭이 행해졌음을 잘 뒷 받침해준다. 또한 담수성 조류는 변함없이 산출되는 반면, 해양성조류인 와편모류가 산출되지 않는 것으로 보아 해안환경에서 다소 멀 어진