• Biomolecules & Therapeutics
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• v.9 no.2
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• pp.88-95
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• 2001

(+)-Methamphetamine (METH) is a psychostimulant, which has been the most popular abused drug in Korea. The rewarding mechanism in METH abuse has been reported to be mediated by dopaminergic system. Recently, it has been reported that dopamine releaser (phentermine) plays a dominant role in the discriminative stimulus effects of METH, whereas 5-HT releaser (fenfluramine) can strongly modify METH self-administration. The present study is designed to assess the behavioral changes and the changes of the serotonin receptors in the brains of rats administered repeated of self-administered METH. The repeated administration of 1.0 mg/kg/day METH for 12 days increased locomotor activities, and there was no difference between i.v. and i.p. treatment. Rats had actively acquired METH self-administration for 3 weeks at 0.1 or 0.2 mg/kg/injection. Whereas, it was taken few days to acquire sucrose pellet self-administration. The binding of [$^3$H]-8-hydroxy-DPAT (5-H $T_{1A}$ receptors) and [$^3$H]-5-carboxytryptamine (5-H $T_{1B}$ receptors) to brain sections was examined. Both passive administration and self-administration of METH did not change significantly the serotonin receptors levels in hippocampus, striatum and nucleus accumbens. These results suggest that serotonin receptors may not change in the acquisition period of METH self-administration, and we are trying to investigate the serotonin receptors levels of brain in rats maintained of METH self-administration.n.n.

• Journal of Korean Medicine for Obesity Research
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• v.16 no.1
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• pp.27-35
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• 2016

Objectives: This study investigated the effects of water extract of Coix lacrymajobi var. mayuen on obesity and its associated factors in high fat diet (HFD) induced obese mice. Methods: Male C5BL/6 mice were randomly assigned to 4 groups, normal group (chow diet), a HFD, HFD with water extract of Coix lacrymajobi var. mayuen 100 mg/kg (W-Coix), and HFD with phentermine 5 mg/kg (Phen) as positive control. Body weight, food intake, fasting blood glucose were checked every week and then organs, blood serums were collected after 16 weeks of treatment. Results: Body weight and adipocyte size were significantly lesser in W-Coix than in HFD group; however energy efficiency in W-Coix were not different with HFD. The oral glucose tolerance test, serum glucose and insulin were significantly decreased in W-Coix, also lipid accumulations in liver tissue and lipid levels (total cholesterol, high density lipoprotein-cholesterol) were improved with W-Coix treatment. However skeletal muscle loss with HFD was not changed in W-Coix compared with HFD group. Conclusions: The W-Coix treatment decreased body weight, adipocyte size and it is associated with improved glucose and lipid metabolism. Further studies are needed to know the mechanism of antiobesity in W-Coix.

• Analytical Science and Technology
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• v.33 no.1
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• pp.23-32
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• 2020

Methamphetamine (MA) is the most common and available drug of abuse in Korea and its primary metabolite is amphetamine (AP). Detection of AP derivatives, such as MA, AP, phentermine (PT), MDA, MDMA, and MDEA by the use of immunoassay screening is not reliable and accurate due to cross-reactivity and insufficient specificity/sensitivity. Therefore, the analytical process accepted by most urine drug-testing programs employs the two-step method with an initial screening test followed by a more specific confirmatory test if the specimen screens positive. In this study, a gas chromatography-mass spectrometric (GC-MS) method was developed and validated for confirmation of MA and AP in human urine. Urine sample (500 µL) was added with N-isopropylbenzylamine as internal standard and ethyl chloroformate as a derivatization reagent, and then extracted with 200 µL of ethyl acetate. Extracted samples were analysed with GC-MS in the SIM/ Scan mode, which were screened by Cobas c311 analyzer (Roche/Hitachi) to evaluate the efficiency as well as the compatibility of the GC-MS method. Qualitative method validation requirements for selectivity, limit of detection (LOD), precision, accuracy, and specificity/sensitivity were examined. These parameters were estimated on the basis of the most intense and characteristic ions in mass spectra of target compounds. Precision and accuracy were less than 5.2 % (RSD) and ±14.0 % (bias), respectively. The LODs were 3 ng/mL for MA and 1.5 ng/mL for AP. At the screening immunoassay had a sensitivity of 100% and a specificity of 95.1 % versus GC-MS for confirmatory testing. The applicability of the method was tested by the analysis of spiked urine and abusers' urine samples.

• YAKHAK HOEJI
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• v.55 no.2
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• pp.145-153
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• 2011

A simultaneous detection and quantification method for determining the Phenylalkylamine derivatives, such as methamphetamine (MA), amphetamine (AM), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), ketamine (KT), norketamine (NKT), phentermine (PT), fenfluramine (FFA) and phenmetrazine (PM), in oral fluid was developed and validated according to international guidelines. The validated method was applied to actual oral fluid samples collected from drug abuse suspects. The recovery of phenylalkylamines from oral fluid collection devices was also assessed. Oral fluid specimens from 20 drug abuse suspects submitted by the police were collected using Salivette$^{TM}$, Quantisal$^{TM}$ or direct expectoration. The samples were screened using a biochip array analyzer. For confirmation, the samples were analyzed by GC-MS in selected-ion monitoring (SIM) mode after extraction using automated SPE with a mixed-mode cation exchange cartridge and derivatization with trifluoroacetic anhydride (TFAA). The results from the immunoassay were consistent with those from GC-MS. All the oral fluid samples gave positive results for MA, AM, PT and/or PM. The detection of phenylalkylamines in oral fluid can provide a better indication of recent use than urine or hair. Therefore, the oral fluid specimen was useful for demonstrating phenylalkylamines abuse in the driving under the influence of drug (DUID) as an alternative specimen for urine.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.761-766
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• 2020

Phenylamine derivatives are substances that have a biochemical action and are widely applied as psychotropic drugs. In particular, with regard to the quantitative analysis of substances such as ephedrine, amphetamine, pentermine, and dopamine, many previous studies such as electrochemical, vacuum ultraviolet method, and gas chromatography have been conducted. However, there have not been many studies on the structural characteristics of molecular units. Therefore, In this study, we used (HyperChem8.0's, HC) semi-empirical PM3 method to calculate the total energy, band gap, electrostatic potential, and net charge of ephedrine, amphetamine, pentamine and dopamine to investigate the chemical properties of each derivative according to the molecular structure change. The results showed that for total energy -43,171.8, -32,9538.3, -36,407.3 and -43,061.2 Kcal/mol, respectively, while for band gaps, 10.16379377, 9.9531666, 9.7878002 and 9.0589282 eV. Also, for electrostatic potentials, 1.301~-0.045, 1.694~0.299, 0.694~-0.158 and 1.587~-0.048 respectively. Finally, looking at the distribution of net charges, the oxygen atoms, nitrogen atoms and carbon atoms were -0.312~-0.242, -0.161~-0.051 and +0.13~-0.12 respectively. These results are expected to lead to chemical action centered on phenyl radicals and oxygen and nitrogen atoms common to phenethylamine derivatives.