• Environmental Analysis Health and Toxicology
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• v.18 no.1
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• pp.21-25
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• 2003

카바메이트계 농약인 카보푸란은 어류에 대한 독성이 매우 높으며, 낮은 농도에서 어류의 척추기형이나 행동이상을 유발한다. 이러한 카보푸란의 독성기전을 밝히기 위한 일환으로 신경물질대사와 관련이 깊은 acetylcholine esterase(AChE)와 monoamine oxidase(MAO)에 미치는 농약의 효과를 송사리(Oryzias latipes; Medaka fish)를 이용하여 평가하였다. Medaka fish에 대한 카보푸란의 반수치사농도(LC$_{50}$)는 2.5 ppm이었으며, 1 ppb 카보푸란에 24시간 노출된 경우, AChE 효소활성이 머리와 몸통부위에서 각각 30, 20%씩 감소되었다. 한편, MAO 효소활성은 카보푸란의 농도가 증가함에 따라 머리부위에서는 감소한 반면, 몸통부위에서는 증가하는 경향을 보였다. 특히 카보푸란의 농도가 1 ppb에서도 송사리의 MAO 효소활성이 영향을 받는 것으로 나타나, 카보푸란에 의한 송사리의 행동이상은 AChE 활성 뿐 아니라 MAO활성의 변화에 의한 복합적인 효과일 가능성이 높다.

• Korean Journal of Pharmacognosy
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• v.38 no.1
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• pp.27-30
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• 2007

We examined the inhibitory activities against monoamine oxidase (MAO) of Chrysanthemum indicum L. in vitro and in vivo methods. Methanolic extract of C. indicum showed significant inhibitory activities on MAO-A that were prepared from rat brain in vitro. The inhibitory activities were measured by serotonin as a substrate. The $IC_{50}$ value of methanolic extract of C. indicum was 0.24 mg/ml for the inhibition of MAO-A. The ethylacetate fraction of methanolic extract of C. indicum exhibited the best activity toward MAO-A with $IC_{50}$ value of 0.05 mg/ml in vitro. It was observed that those activities in vivo tests have different tendency each other. Ethanolic extract of C. indicum was have no effect on rat MAO by the oral administration (p<0.05). However, MAO inhibitory activities of ethanolic extract of C. indicum by the oral administration have similar tendency to those of iproniazid. Consequently, we suggest that C. indicum may have the effects on the inhibitory activities against MAO both in vitro and in vivo. These results indicates that the C. indicum extract has properties indicative of potential neuroprotective ability.

• Herbal Formula Science
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• v.17 no.2
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• pp.143-150
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• 2009

The effects of aqueous extract of Schizandrae Fructus (AESC) on lead (Pb)-induced changes of monoamine neurotransmitters in the hippocampus (HIP) of adult rats were investigated. Male Sprague-Dawley rats were received intraperitoneal (i.p.) administration of Pb acetate (5 mg/kg/d) for 28 days and sacrificed 7 days after the last administration. Concentrations of norepinephrine (NE), dopamine (DA), serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIAA) in HIP were measured by HPLC. There were significant decreases of NE, DA, 5-HT and 5-HIAA in Pb treated rats (P < 0.05), while pretreatment with AESC (100 mg/kg/d or 300 mg/kg/d, p.o., 2 h before Pb) greatly inhibited the decrease of monoamine transmitters, respectively (P < 0.05). Also, AESC (300 mg/kg/d) significantly increased the reduction of glutathione contents and superoxide dismutase activities in HIP induced by chronic Pb. These results suggest that AESC ameliorates Pb-induced depletion of monoamine neurotransmitters in HIP through its antioxidant activity.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.190-194
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• 2005

In our search for monoamine oxidase (MAO) inhibitors from natural resources, we found that the methanol extract of the roots of Sophora flavescens showed an inhibitory effect on mouse brain monoamine oxidase (MAO). Bioactivity-guided isolation of the extract yielded two known flavonoids, formononetin (1) and kushenol F (2), as active compounds along with three inactive compounds, oxymatrine (3), trifolirhizin (4), and ${\beta}$-sitosterol (5). Formononetin (1) and kushenol F (2) showed significant inhibitory effects on MAO in a dose-dependent manner with $IC_{50}$ values of 13.2 and $69.9\;{\mu}M$, respectively. Formononetin (1) showed a slightly more potent inhibitory effect against MAO-B ($IC_{50}:\;11.0\;{\mu}M$) than MAO-A ($IC_{50}:\;21.2\;{\mu}M$). Kushenol F (2) also preferentially inhibited the MAO-B activity than MAO-A activity with the $IC_{50}$ values of 63.1 and $103.7\;{\mu}M$, respectively.

• The Korean Journal of Pharmacology
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• v.20 no.2
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• pp.73-80
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• 1984

The effect of higenamine and its derivatives on the activity of rat bran mitochondrial monoamine oxidase(MAO) was studied. Methoxyhigenamine of drugs tested had no effect on isometric contraction of heart and reversibly inhibited MAO towards 5-hydroxytryptamine(5-HT) and phenylethylamine(PEA) in a pure competitive fashion and in a hyperbolic mixed fashion, respectively, but was found to be relatively MAO-A selective inhibitor, with IC50 value for 5-HT lower ten fold than for PEA. The results suggest that methoxyhigenamine is a reversible, relatively MAO-A specific inhibitor in virto.

• Toxicological Research
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• v.14 no.4
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• pp.495-500
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• 1998

The effect of acute toluene exposure on behaviour and monoamine concentrations in the various brain regions were investigated in the rat. Toluene was adminstered via inhalation to rats at concentrations of 0, 1000, 10000, 40000 ppm for 20 min. During exposure to toluene, spontaneous locomotor activity was counted. After exposure, animals were sacrificed instantly and brains were separated. Regional concentratons of brain monoamines (norepinephrine, NE; dopamine, DA; 5- hydroxytryptamine, 5-HT) and its metabolites (3,4-dihydroxyphenylacetic acid, DOPAC; homovanillic acid, HVA; 5-hydroxyindole-3-acetic acid, 5-HIAA) were determined. The changes in locomotor activity during toluene exposure depended on the toluene concentration. At 1000 ppm concentration, spontaneous locomotor activity increased initially and thereafter decreased. At higher concentrations (10000 ppm and 40000 ppm), spontaneous locomotor activity decreased and eventually ceased. A regional analysis of VA, NE, 5-HT, VOPAC, HVA, and 5-HIAA indicated a significant decrease in VA concentrations in cerebellum and striatum while NE and 5-HT concentrations were significantly increased in the cerebellum and cortex. 5-HIAA concentrations were significantly increased in all brain regions. DOPAC concentrations were significantly increased in cerebellum and cortex while decreased in striatum. These results especially indicated that metabolic conversion of DA to HVA in striatum was highly increased by toluene inhalation. However, It remains to elucidate between behavioural responses and monoamine changes.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.347-355
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• 2004

This study was undertaken in order to evaluate effects of methanol extracts of Stachys sieboldii MIQ and its related enzyme activities in brain tissues of rats. Sprague-Dawley(SD) male rats were fed within a control group, which is a basic diet group. The experimental diet group was given 100 and 200 mg/kg to supervise 100 and 200 mg/kg body weight per day for 20 days. Lipid peroxide levels and acetylcholine esterase activity in brain tissues were slightly decreased at a dose dependent manner, in vitro. Lipid peroxide levels were also decreased at a dose dependent manner; methanolic extracts of Stachys sieboldii MIQ demonstrated significant inhibitory effects, in vivo. Monoamine oxidase and xanthine oxidase activities were significantly inhibited in the brain tissues of experimental group compared to control group and the ratio of type conversion of xanthine oxidase were decreased.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.789-794
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• 2003

Purpose : We intended to evaluate the effect of hypoxia-ischemia on extracellular striatal monoamine metabolism in neonatal rat brains by in vivo microdialysis. Methods : The right common carotid arteries of five or six-day old rats were surgically ligated, and the probes for microdialysis were inserted into the right striatum with stereotaxic instrument. After stabilization for two hours, artificial cerebrospinal fluid was infused via the probe for microdialysis and samples were collected during hypoxia-ischemia and recovery periods at 20 minute intervals. The concentrations of DA(dopamine), DOPAC(3,4-di-hydroxyphenyl acetic acid), HVA(homovanillic acid), NE(norepinephrine), and 5-HIAA(5-hydroxy indole-acetic acid) were measured by HPLC(high performance liquid chromatography) and the changes were analysed. Results : The striatal levels of dopamine metabolites such as DOPAC and HVA, were significantly decreased during hypoxia-ischemia, and increased to their basal level during reoxygenation(P<0.05). Dopamine mostly increased during hypoxia but statistically not significant(P>0.05). DOPAC showed the most remarkable decrease($23.0{\pm}4.2%$, P<0.05), during hypoxia-ischemia and increase to the basal levels during reoxygenation($120.8{\pm}54.9%$, P<0.05), and HVA showed the same pattern of changes as those of DOPAC during hypoxia-ischemia($35.3{\pm}7.6%$ of basal level, P<0.05) and reoxygenation ($105.8{\pm}32.3%$). However, the level of NE did not show significant changes during hypoxia-ischemia and reoxygenation. The levels of 5-HIAA decreased($74.9{\pm}3.1%$) and increased($118.1{\pm}7.8%$) during hypoxia-ischemia and reoxygenation, respectively(P<0.005). Conclusion : Hypoxia-ischemia had a significant influence on the metabolism of striatal monoamine in neonatal rat brains. These findings suggest that monoamine, especially dopamine, and its metabolites could have a significant role in the pathogenesis of hypoxic-ischemic injury of neonatal rat brains.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.230-239
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• 1988

Thirty kinds of medicinal plants were screened to examine inhibitory activities on rat brain monoamine oxidase A, using serotonin as a substrate. As active principles, various kinds of stilbenes were isolated from Veratri Rhizoma, Reynoutriae Radix and Rhei undulati Rhizoma, and several kinds of flavonoids from Sophorae Flos, Chrisanthemi Flos and Glycine max. Among the compounds isolated, resveratrol(I) strongly inhibited MAO-A competitively, and its $IC_{50}$ and Ki values were 2 ${\mu}M$ and 2.5 ${\mu}M$, respectively. Inhibitory potencies towards MAO-A of some stilbenes and flavonoids were also compared.

• Natural Product Sciences
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• v.11 no.3
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• pp.145-149
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• 2005

A methanol soluble extract from the dried hooks and stems of Uncaria rhynchophylla showed a strong inhibitory activity against monoamine oxidase in mouse brain. Using a bioassay-guided purification of this extract, a known ${\beta}-carboline$ type alkaloid, harman (1), was obtained as an active constituent. In addition, five known indole alkaloids, isocorynoxeine (2), isorhynchophylline (3), corynoxeine (4), cadambine (5), and $3{\alpha}-dihydrocadambine$ (6), were isolated and found to be weakly active or inactive.