• Korean Journal of Biological Psychiatry
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• v.8 no.2
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• pp.208-219
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• 2001

The pharmacotherapy of schizophrenia exhibits wide inter-individual variabilities in clinical efficacy and adverse effects. Recently, human genetic diversity has been known as one of the essential factors to the variation in human drug response. This suggests that drug therapy should be tailored to the genetic characteristics of the individual. Pharmacogenetics is the field of investigation that attempts to elucidate genetic basis of an individual's responses to pharmacotherapy, considering drug effects divided into two categories as pharmacokinetics and pharmacodynamics. The emerging field of pharmacogenomics, which focuses on genetic determinants of drug response at the level of the entire human genome, is important for development and prescription of safer and more effective individually tailored drugs and will aid in understanding how genetics influence drug response. In schizophrenia, pharmacogenetic studies have shown the role of genetic variants of the cytochrome P450 enzymes such as CYP2D6, CYP2C19, and CYP2A1 in the metabolism of antipsychotic drugs. At the level of drug targets, variants of the dopamine $D_2$, $D_3$ and $D_4$, and 5-$HT_{2A}$ and 5-$HT_{2C}$ receptors have been examined. The pharmacogenetic studies in schizophrenia presently shows controversial findings which may be related to the multiple involvement of genes with relatively small effects and to the lack of standardized phenotypes. For further development in the pharmacogenomics of schizophrenia, there would be required the extensive outcome measures and definitions, and the powerful new tools of genomics, proteomics and so on.

• Journal of Korean Medicine for Obesity Research
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• v.4 no.1
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• pp.139-160
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• 2004

The obesity is detrimental to the health of people living in affluent societies. Individual differences in energy metabolism are caused primarily by single nucleotide polymorphisms(SNPs), some of which promote the development of obesity-related type 2 diabetes mellitus. Type 2 diabetes mellitus is a common multifactorial genetic syndrome, which is determined by several different genes and environmental factors. In this review, five major conclusions are reached: (1)To be clinically significant, SNPs must be relevant, prevalent, modifiable, and measurable. (2)Differences in SNPs may have been caused by famine, ultraviolet light, alcohol, climate, agricultural revolution. livestock, lactase persistence, and westernized lifestyle. (3)Candidate obesity genes of calorie intake restriction are SIM 1, MC3R, MC4R, AGRP, CART, CCK, CNTFR, DRD2, Ghrelin, 5-HT receptor, NPY, PON and those of energy metabolism are LEP, LEPR, UCP1, UCP2, UCP3, B2AR, B3AR, PGC-1, Androgen receptor and those of fat mobilization are AGT, ACE, ADA, APM1, Apolipoproteins, PPAR, FABP, FOXC2, GCGR, $11-{\beta}HSDI$, LDLR, Hormonal sensitive lipase, Perilipin, $TNF-{\alpha}$, $TNF-{\beta}$ (4)Candidate obesity genes in the eastern are NPY, LEP, LEPR, UCP1, UCP2, UCP3, B2AR, B3AR, ACE, APM1, PPAR, and FABP. (5)Candidate obesity genes in type 2 diabetes mellitus are MC3R, MC4R, B2AR, B3AR, ADA, APM1, PPAR, FABP, FOXC2, PC1, PC2, ABCC8, CAPN10, CYP19, CYP7, ENPP1, GCK, GYS1, IGF, IL-6, Insulin receptor, IRS, and LPL. The discovery of SNPs will lead to a greater understanding of the pathogenesis of obesity and to better diagnostics, treatment, and eventually prevention.

• Korean Journal of Biological Psychiatry
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• v.5 no.1
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• pp.34-45
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• 1998

We provide the reader with a brief introduction to the neurobiology of neuropeptides. Several comprehensive reviews of the distribution and neurochemical, neurophysiological, neuropharmacological and behavioral effects of the major neuropeptides have recently appeared. In reviews of the large number of neuropeptides in brain and their occurance in brain regions thought to be involved in the pathogenesis of major psychiatric disorders, investigators have sought to determine whether alternations in neuropeptide systems are associated with schizophrenia, mood disorders, anxiety disorders, alcoholism and neurodegenerative disease. There is no longer any doubt that neuropeptide-containing neurons are altered in several neuropsychiatric disorders. One of the factors that has hindered neuropeptide research to a considerable extent is the lack of pharmacological agents that specifically alter the synaptic availability of neuropeptides. With the exception of naloxone and naltrexone, the opiate-receptor antagonists, there are few available neuropeptide- receptor antagonists. Two independent classes of neuropeptide-receptor antagonists has been expected to be clinically useful. Naltrexone, a potent ${\mu}$-receptor antagonist, has been used successfully to reduce the need for alcohol consumption. And cholecycstokinin antagonists are now in development as a new class of anxiolytics, which would be expected to be free from tolerance and physical dependence and lack of sedation. In this review, we deal with these two kinds of neuropeptide system, the opioid system and cholesystokinins in the brain. The role of opioid systems in the reinforcement after alcohol consumtion and that of cholesystokinins in the pathogenesis of anxiety will be discussed briefly. As we know, the future for neuropeptides in psychiatry remains bright indeed.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.187-192
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• 2012

In the present study, the antinociceptive profiles of hop extract were characterized in ICR mice. Hop extract administered orally (from 25 to 100 mg/kg) showed an antinociceptive effect in a dose-dependent manner as measured in the acetic acid-induced writhing test. Antinociceptive action of hop extract was maintained at least for 60 min. Moreover, cumulative response time of nociceptive behaviors induced with intraplantar formalin injection was reduced by hop extract treatment during the 2nd phases. Furthermore, the cumulative nociceptive response time for intrathecal injection of substance P ($0.7{\mu}g$) or glutamate ($20{\mu}g$) was diminished by hop extract. Intraperitoneal pretreatment with naloxone (an opioid receptor antagonist) attenuated antinociceptive effect induced by hop extract in the writhing test. However, methysergide (a 5-HT serotonergic receptor antagonist) or yohimbine (an ${\alpha}_2$-adrenergic receptor antagonist) did not affect antinociception induced by hop extract in the writhing test. Our results suggest that hop extract shows an antinociceptive property in various pain models. Furthermore, the antinociceptive effect of hop extract may be mediated by opioidergic receptors, but not serotonergic and ${\alpha}_2$-adrenergic receptors.

• Advances in Traditional Medicine
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• v.5 no.3
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• pp.201-208
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• 2005

Earlier we have reported the antidiabetic activity of fresh juice of rhizomes of Zingiber officinale (Z. officinale) and its correlation with 5-HT receptor antagonism. Since 6-gingerol the marker compound of Z. officinale is reported to posses 5-HT anatgonistic activity, the present investigation, was undertaken to find out the concentration of 6-gingerol present in methanolic extract of Z. officinale and its different fractions (petroleum ether, toluene and chloroform). We also evaluated these fractions for antidiabetic activity in streptozotocin (STZ)-induced neonatal type 2 diabetic rats. Fasting glucose and insulin levels in non insulin dependent diabetes mellitus (NIDDM) rats were found to be significantly (P < 0.05) higher than control rats and these were significantly decreased by treatment with methanolic extract of Z. officinale and its fractions. The results of oral glucose tolerance test (OGTT) showed that methanolic extract and its fractions significantly (P < 0.05) decreased both STZ-induced increase in $AUC_{glucose}$ and $AUC_{insulin}$ values in NIDDM groups. Treatment with petroleum ether fraction produced a greater reduction in elevated glucose and $AUC_{glucose}$ levels as compared to treatment with other fractions. Treatment with methanolic extract of Z. officinale and its fractions also produced significant reduction in the elevated lipid, serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) levels in NIDDM rats. The effect of petroleum ether fraction on elevated lipid, SGOT and SGPT levels was significantly greater as compared to treatment with other fractions. The concentration of 6-gingerol was found to be maximum in petroleum ether fraction (11.430%) and minimum in chloroform fraction (0.973%). The methanolic extract and toluene fraction was found to contain 3.080% and 2.191 %, 6-gingerol respectively. In conclusion, our data suggest that methonolic extract and its fractions possess significant antidiabetic activity in NIDDM rats. The extent of activity appears to be dependent on the concentration of 6-gingerol present in the extract or its fractions.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.5
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• pp.377-381
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• 2014

Propofol is a widely used anesthetic. Many studies have shown that propofol has direct effects on blood vessels, but the precise mechanism is not fully understood. Secondary intrapulmonary artery rings from male rats were prepared and mounted in a Multi Myograph System. The following constrictors were used to induce contractions in isolated artery rings: high $K^+$ solution (60 mmol/L); U46619 solution (100 nmol/L); 5-hydroxytryptamine (5-HT; $3{\mu}mol/L$); or phenylephrine (Phe; $1{\mu}mol/L$). The relaxation effects of propofol were tested on high $K^+$ or U46619 precontracted rings. Propofol also was added to induce relaxation of rings preconstricted by U46619 after pretreatment with the nitric oxide synthase inhibitor $N^G$-nitro-L-arginine methyl ester (L-NAME). The effects of propofol on $Ca^{2+}$ influx via the L-type $Ca^{2+}$ channels were evaluated by examining contraction-dependent responses to $CaCl_2$ in the absence or presence of propofol (10 to $300{\mu}mol/L$). High $K^+$ solution and U46619 induced remarkable contractions of the rings, whereas contractions induced by 5-HT and Phe were weak. Propofol induced dose-dependent relaxation of artery rings precontracted by the high $K^+$ solution. Propofol also induced relaxation of rings precontracted by U46619 in an endothelium-independent way. Propofol at different concentrations significantly inhibited the $Ca^{2+}$-induced contractions of pulmonary rings exposed to high $K^+$-containing and $Ca^{2+}$-free solution in a dose-dependent manner. Propofol relaxed vessels precontracted by the high $K^+$ solution and U46619 in an endothelium-independent way. The mechanism for this effect may involve inhibition of calcium influx through voltage-operated calcium channels (VOCCs) and receptor-operated calcium channels (ROCCs).

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.1
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• pp.17-22
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• 2011

Quercetin mainly exists in the skin of colored fruits and vegetables as one of flavonoids. Recent studies show that quercetin, like other flavonoids, has diverse pharmacological actions. However, relatively little is known about quercetin effects in the regulations of ligand-gated ion channels. In the previous reports, we have shown that quercetin regulates subsets of homomeric ligand-gated ion channels such as glycine, 5-$HT_{3A}$ and ${\alpha}7$ nicotinic acetylcholine receptors. In the present study, we examined quercetin effects on heteromeric neuronal ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor channel activity expressed in Xenopus oocytes after injection of cRNA encoding bovine neuronal ${\alpha}3$ and ${\beta}4$ subunits. Treatment with acetylcholine elicited an inward peak current ($I_{ACh}$) in oocytes expressing ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor. Co-treatment with quercetin and acetylcholine inhibited $I_{ACh}$ in oocytes expressing ${\alpha}3{\beta}4$ nicotinic acetylcholine receptors. The inhibition of $I_{ACh}$ by quercetin was reversible and concentration-dependent. The half-inhibitory concentration ($IC_{50}$) of quercetin was $14.9{\pm}0.8\;{\mu}M$ in oocytes expressing ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor. The inhibition of $I_{ACh}$ by quercetin was voltage-independent and non-competitive. These results indicate that quercetin might regulate ${\alpha}3{\beta}4$ nicotinic acetylcholine receptor and this regulation might be one of the pharmacological actions of quercetin in nervous systems.

• Mass Spectrometry Letters
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• v.9 no.3
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• pp.86-90
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• 2018

Methallylescaline, 2-(3,5-dimethoxy-4-[(2-methylprop-2-en-1-yl)oxy]phenyl)ethanamine, is a new psychoactive substance with potent agonist of 5-HT receptor, but there is little information on its pharmacological effect, metabolism, and toxicity. It is necessary to characterize the metabolic profiling of methallylescaline in human hepatocytes using liquid chromatography-high resolution mass spectrometry. Methallylescaline was metabolized to three hydroxy-methallylescaline (M1-M3) and dihydroxy-methallylescaline (M4) via hydroxylation in human hepatocytes. CYP2D6, CYP2J2, CYP1A2, and CYP3A4 enzymes were responsible for the metabolism of methallylescaline. The metabolites as well as methallylescaline would be used for monitoring the abuse of methallylescaline.

• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.421-426
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• 1997

We evaluated the in vivo kinetics, distribution, and pharmacology of N-(4-[$^{18}F$]fluoromethylbenzyl)spiperone ([$^{18}F$]FMBS), a newly developed derivative of spiperone, as a potentially more selective radiotracer for the dopamine (DA) $D_2$ receptors. Mice received 1.9-3.7 MBq (1.8-3.6 nmol/kg) of [$^{18}F$]FMBS by tail vein injection. The time course and regional distribution of the tracer in brain were assessed. Blocking studies were carried out by intravenously preinjecting DA $D_2$ receptor blockers (spiperone, butaclamol) as well as drugs with high affinity for DA $D_1$ (SCH 23390), DA transporter (GBR 12909), and serotonin $S_2$ ($5-HT_2$) (ketanserin) sites. After injection of the tracer, the radioactivity in striatum increased steadily over time, resulting in a striatal-to-cerebellar ratio of 4.8 at 120 min postinjection. By contrast, the radioactivity in cerebellum, frontal cortex, and remaining cortex washed out rapidly. Preinjection of unlabeled FMBS (1 mg/kg) and spiperone (1 mg/kg) reduced [$^{18}F$]FMBS striatal-to-cerebellar ratio by 41% and 80%, respectively. (+)-Butaclamol (1 mg/kg) blocked 80% of the striatal [$^{18}F$]FMBS binding, while (-)-butaclamol (1 mg/kg) did not. Preinjection of SCH 23390 (1 mg/kg) and GBR 12909 (5 mg/kg) had no significant effect on [$^{18}F$]FMBS binding. Ketanserin (1 mg/kg), a ligand for the $5-HT_2$ receptors, did not cause significant inhibition either in striatum, in frontal cortex, or the remaining cortex. The results demonstrate that [$^{18}F$]FMBS labels DA $D_2$ receptors selectively in vivo in the mouse brain. It may hold promise as a selective radiotracer for studying DA $D_2$ receptors in vivo by PET.

• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.189-193
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• 1993

Exposure of dissociated cultures from fetal rat brainstem to glutamate for upto 6 h decreased cellular contents of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid in a concentration- and time-dependent manner. In addition, glutamate induced lactate dehydrogenase leakage. Tetrodotoxin did not block the effects induced by glutamate. MK-801 $(1{\mu}M)$, an N-methyl-D-aspartate (NMDA) channel blocker, but not 6-cyano-2,3-dihydroxy-7-nitro-quinoxazoline $(CNQX;\;3{\mu}M)$, a non-NMDA receptor antagonist, blocked glutamate-induced effects, indicating that these glutamate-induced responses are mediated through NMDA receptors.