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PubMed1998

Methamphetamine--properties and analytical methods of enantiomer determination.

Methamphetamine is one of the most frequently abused drugs of today. Due to its stereogenic center, it can exist as single enantiomer. Like many other chiral compounds, methamamphetamine enantiomers exhibit different pharmacological effects on living organisms. For this reason, it is necessary to develop enantioselective and sufficiently sensitive methods of determination. This review focuses on methamphetamine with an accent on analytical chemistry and especially on chiral separations of this toxicologically important compound.

Animals↗
PubMed1996

Capillary electrophoretic enantioseparation of selegiline, methamphetamine and ephedrine using a neutral beta-cyclodextrin epichlorhydrin polymer.

This paper describes the development of a capillary zone electrophoretic method for chiral separation of three basic compounds of the selegiline synthetic pathway: ephedrine, methamphetamine and selegiline. The method developed allows one to separate the studied compounds in one run using a neutral beta-cyclodextrin epichlorhydrin polymer. The effect of various experimental parameters, such as chiral selector concentration, concentration and composition of background electrolyte, pH, temperature, and the addition of some organic solvents, on the resolution and migration time is discussed. For selegiline and methamphetamine, it is possible, under optimal conditions, to quantify less than 0.5% of the minor isomer in an excess of the major one.

Cyclodextrins↗
PubMedDate not supplied

Relapse of panic disorder induced by a single intravenous methamphetamine injection.

The authors reports a case of a 33-year-old woman who had a relapse and worsening of panic disorder following a single injection of methamphetamine after a long period of remission. Her first panic attack had occurred when she was a 14-year-old high school student, but the course had persisted only for 1 month. Soon after an intravenous injection of methamphetamine, she had a relapse of panic disorder, and depression and agoraphobia developed. Psychotropic medication was not fully effective.

Adult↗
PubMed2002

Low N-acetyl-aspartate and high choline in the anterior cingulum of recently abstinent methamphetamine-dependent subjects: a preliminary proton MRS study. Magnetic resonance spectroscopy.

Studies based on animal models report that methamphetamine (MA) abuse diminishes dopamine (DA) and serotonin innervation in frontal brain regions. In this in vivo human study, we used proton magnetic resonance spectroscopy (MRS), which yields measures of N-acetyl-aspartate (NAA), a marker of living neurons, to examine frontal brain regions possibly affected by methamphetamine dependence (MD). We tested the hypothesis that MD subjects would exhibit abnormally low levels of NAA, referenced to creatine (Cr), in anterior cingulate gray matter. We further hypothesized that the primary visual cortex, which receives relatively less DA innervation than the frontal brain regions, would show normal NAA/Cr ratios in MD subjects. Subjects included nine MD men (mean+/-standard deviation (S.D.)=32.5+/-6.4 years) and nine age-matched control men (mean+/-S.D.=32.7+/-6.8 years). The MD subjects were MA-free for 4-13 weeks. Proton MRS metabolites were expressed as ratios of creatine; the absolute values of which did not distinguish controls and MD subjects. With regard to metabolite ratios, the MD men had significantly lower NAA/Cr in the cingulum (mean+/-standard error (S.E.): control=1.46+/-0.03; MD=1.30+/-0.03; Mann-Whitney P=0.01) but not in the visual cortex (mean+/-S.E.: control=1.64+/-0.06; MD=1.69+/-11; Mann-Whitney P=0.52) relative to controls. These results provide evidence for NAA/Cr deficit that is selective to the anterior cingulum, at least with respect to visual cortex, in MD subjects. The neuronal compromise that these changes reflect may contribute to the attentional deficits and dampened reward system in MD.

Adult↗
PubMed2006

Determination of the synthetic origin of methamphetamine samples by 2H NMR spectroscopy.

Samples of methamphetamine, prepared according to the most common synthetic pathways, were submitted to natural-abundance 2H NMR spectroscopy. The deuterium content at the various sites of the molecule was found to depend on its synthetic history. The technique provides a chemical fingerprint of methamphetamine samples and can give hints to trace back the starting materials and the synthetic procedures.

Deuterium↗
PubMed2006

Rotational spectra and conformational structures of 1-phenyl-2-propanol, methamphetamine, and 1-phenyl-2-propanone.

Microwave spectra have been recorded for 1-phenyl-2-propanol, methamphetamine, and 1-phenyl-2-propanone from 11 to 24 GHz using a Fourier-transform microwave spectrometer. Only one spectrum from a single conformational isomer was observed for each species. The rotational transitions in the spectrum of 1-phenyl-2-propanone were split into separate transitions arising from the A- and E-torsional levels of the methyl rotor. The fit of the E-state transitions to a "high-barrier" internal rotation Hamiltonian determines V3 = 238(1) cm-1 and rotor-axis angles of thetaa = 87.7(5) degrees, thetab = 50.0(5) degrees, and thetac = 40.0(5) degrees. Ab initio optimizations (MP2/6-31G**) and single-point calculations (MP2/6-311++G**) were used to model the structures of 1-phenyl-2-propanol, methamphetamine, and 1-phenyl-2-propanone. The lowest energy conformations of these species were found to be stabilized by weak OH-pi, NH-pi, and CH-pi hydrogen-bonding interactions. Moments of inertia, derived from the model structures, were used to assign the spectra to the lowest energy conformation of each species. A series of MP2/6-31G* partial optimizations along the internal rotation pathway were used to estimate the barrier to methyl rotation to be 355 cm-1 for 1-phenyl-2-propanone.

Acetone↗
PubMed2005

Preliminary findings of noncompliance with psychotropic medication and prevalence of methamphetamine intoxication associated with suicide completion.

OBJECTIVE: A study of medical examiner records from suicide completers was designed to identify potential precipitating factors in the decision to commit suicide. METHODS: Forensic data has been collected for a subset of suicide victims in Utah who completed suicide between 1996 and 2002. RESULTS: Youth suicide completers appear to be undiagnosed for mental illness, or to be noncompliant with psychotropic medications. Along with treatment issues, alcohol and methamphetamine were the most common substances found in the blood and/or urine of suicide completers. CONCLUSIONS: Accurate diagnosis of mental illness, and improved compliance with psychotropic medications may play a critical role in suicide prevention. The prevalence of methamphetamine in suicide completers is unexpectedly high and requires further investigation.

Adolescent↗
PubMed1997

Infrared discrimination of enantiomerically enriched and racemic samples of methamphetamine salts.

A relatively rapid and simple means of enantiomer determination is described for the determination of methamphetamine, a common drug of abuse. The method employs the well known technique of infrared transmission spectrometry on solid samples dispersed within an alkali metal halide matrix. This approach exploits the solid-state, ion-exchange reaction between methamphetamine hydrochloride and a potassium iodide matrix and the subsequent formation of the hydriodide salt in situ. The infrared properties of the hydriodide salt are distinct for enantiomerically enriched and racemic samples, and therefore are readily distinguished by infrared transmission spectrometry. This technique uses materials and instrumentation that are generally available to most crime laboratories. The applicability of this method to some other amine drugs is discussed.

Central Nervous System Stimulants↗
PubMed1998

Enantioselective high-performance liquid chromatography with fluorescence detection of methamphetamine and its metabolites in human urine.

A simple, rapid and highly sensitive high-performance liquid chromatographic method with fluorescence detection for determining the enantiomers of methamphetamine and its major metabolites, amphetamine and p-hydroxymethamphetamine, in urine samples was developed. Using a newly developed reagent for amines, namely, 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride, six enantiomers were derivatized under mild conditions (i.e., 10 min at room temperature, pH 9.0) and separated isocratically on a cellulose tris(3,5-dimethylphenylcarbamate) coated silica gel column following a pre-separation on an ODS column within 42 min, and the effluent was monitored at 440 nm (lambda ex 330 nm). Calibration curves for these derivatives using spiked human urine were linear in the range 0.05-100 mumol dm-3 with correlation coefficients > or = 0.999. The detection limits at a signal-to-noise ratio of 3 were 2.8-8.8 fmol per 5 microliters injection. The relative standard deviations of within- (n = 6) and between-day (n = 5) variations were < or = 7.4%. The method was successfully applied to discriminate between (S)-(+)-methamphetamine and its corresponding metabolites found in abusers' urine and their antipodes in a sample taken from a Parkinsonian patient on selegiline (Deprenyl) therapy.

Amphetamine↗
PubMed1972

Metabolism of ( 14 C)methamphetamine in man, the guinea pig and the rat.

1. The metabolites of (+/-)-2-methylamino-1-phenyl[1-(14)C]propane ([(14)C]methamphetamine) in urine were examined in man, rat and guinea pig. 2. In two male human subjects receiving the drug orally (20mg per person) about 90% of the (14)C was excreted in the urine in 4 days. The urine of the first day was examined for metabolites, and the main metabolites were the unchanged drug (22% of the dose) and 4-hydroxymethamphetamine (15%). Minor metabolites were hippuric acid, norephedrine, 4-hydroxyamphetamine, 4-hydroxynorephedrine and an acid-labile precursor of benzyl methyl ketone. 3. In the rat some 82% of the dose of (14)C (45mg/kg) was excreted in the urine and 2-3% in the faeces in 3-4 days. In 2 days the main metabolites in the urine were 4-hydroxymethamphetamine (31% of dose), 4-hydroxynorephedrine (16%) and unchanged drug (11%). Minor metabolites were amphetamine, 4-hydroxyamphetamine and benzoic acid. 4. The guinea pig was injected intraperitoneally with the drug at two doses, 10 and 45mg/kg. In both cases nearly 90% of the (14)C was excreted, mainly in the urine after the lower dose, but in the urine (69%) and faeces (18%) after the higher dose. The main metabolites in the guinea pig were benzoic acid and its conjugates. Minor metabolites were unchanged drug, amphetamine, norephedrine, an acid-labile precursor of benzyl methyl ketone and an unknown weakly acidic metabolite. The output of norephedrine was dose-dependent, being about 19% on the higher dose and about 1% on the lower dose. 5. Marked species differences in the metabolism of methamphetamine were observed. The main reaction in the rat was aromatic hydroxylation, in the guinea pig demethylation and deamination, whereas in man much of the drug, possibly one-half, was excreted unchanged.

Animals↗
PubMed1996

The neuronal nitric oxide synthase inhibitor, 7-nitroindazole, protects against methamphetamine-induced neurotoxicity in vivo.

The present study was undertaken to investigate whether the relatively selective neuronal nitric oxide synthase (NOS) inhibitor, 7-nitroindazole (7-NI), protects against methamphetamine (METH)-induced neurotoxicity. Male Swiss Webster mice received the following treatments (i.p.; q 3 h x 3): (a) vehicle/saline, (b) 7-NI (25 mg/kg)/saline, (c) vehicle/METH (5 mg/kg), and (d) 7-NI (25 mg/kg)/METH (5 mg/kg). On the second day, groups (a) and (b) received two vehicle injections, and groups (c) and (d) received two 7-NI injections (25 mg/kg, each). Administration of vehicle/METH resulted in 68, 44, and 55% decreases in the concentration of dopamine, 3,4-dihydroxyphenylacetic acid, and homovanillic acid, respectively, and a 48% decrease in the number of [3H]mazindol binding sites in the striatum compared with control values. Treatment with 7-NI (group d) provided full protection against the depletion of dopamine and its metabolites and the loss of dopamine transporter binding sites. Administration of 7-NI/saline (group b) affected neither the tissue concentration of dopamine and its metabolites nor the binding parameters of [3H] mazindol compared with control values. 7-NI had no significant effect on animals' body temperature, and it did not affect METH-induced hyperthermia. These findings indicate a role for nitric oxide in methamphetamine-induced neurotoxicity and also suggest that blockade of NOS may be beneficial for the management of Parkinson's disease.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2000

The human nucleus accumbens is highly susceptible to G protein down-regulation by methamphetamine and heroin.

Although the nucleus accumbens is assumed to be a critical brain "pleasure center," its function in humans is unknown. As animal data suggest that a unique feature of this small brain area is its high sensitivity to down-regulation of an inhibitory G protein by drugs of abuse, we compared G protein levels in postmortem nucleus accumbens with those in seven other brain regions of chronic users of cocaine, methamphetamine, and heroin, and of matched controls. Biochemical changes were restricted to the nucleus accumbens in which concentrations of G(alpha)1 and/or G(alpha)2 were reduced by 32-49% in the methamphetamine and heroin users. This selective responsiveness to these abused drugs implies a special role for the human nucleus accumbens in mechanisms of drug reinforcement and suggests that some features of the drug-dependent state (e.g., tolerance) might be related to inhibition of G(alpha)1-linked receptor activity.

Adult↗
PubMed2001

Parallel increases in lipid and protein oxidative markers in several mouse brain regions after methamphetamine treatment.

The neurotoxic actions of methamphetamine (METH) may be mediated in part by reactive oxygen species (ROS). Methamphetamine administration leads to increases in ROS formation and lipid peroxidation in rodent brain; however, the extent to which proteins may be modified or whether affected brain regions exhibit similar elevations of lipid and protein oxidative markers have not been investigated. In this study we measured concentrations of TBARs, protein carbonyls and monoamines in various mouse brain regions at 4 h and 24 h after the last of four injections of METH (10 mg/kg/injection q 2 h). Substantial increases in TBARs and protein carbonyls were observed in the striatum and hippocampus but not the frontal cortex nor the cerebellum of METH-treated mice. Furthermore, lipid and protein oxidative markers were highly correlated within each brain region. In the hippocampus and striatum elevations in oxidative markers were significantly greater at 24 h than at 4 h. Monoamine levels were maximally reduced within 4 h (striatal dopamine [DA] by 95% and serotonin [5-HT] in striatum, cortex and hippocampus by 60-90%). These decrements persisted for 7 days after METH, indicating effects reflective of nerve terminal damage. Interestingly, NE was only transiently depleted in the brain regions investigated (hippocampus and cortex), suggesting a pharmacological and non-toxic action of METH on the noradrenergic nerve terminals. This study provides the first evidence for concurrent formation of lipid and protein markers of oxidative stress in several brain regions of mice that are severely affected by large neurotoxic doses of METH. Moreover, the differential time course for monoamine depletion and the elevations in oxidative markers indicate that the source of oxidative stress is not derived directly from DA or 5HT oxidation.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2004

Methamphetamine produces neuronal inclusions in the nigrostriatal system and in PC12 cells.

Mice treated with the psychostimulant methamphetamine (MA) showed the appearance of intracellular inclusions in the nucleus of medium sized striatal neurones and cytoplasm of neurones of the substantia nigra pars compacta but not in the frontal cortex. All inclusions contained ubiquitin, the ubiquitin activating enzyme (E1), the ubiquitin protein ligase (E3-like, parkin), low and high molecular weight heat shock proteins (HSP 40 and HSP 70). Inclusions found in nigral neurones stained for alpha-synuclein, a proteic hallmark of Lewy bodies that are frequently observed in Parkinson's disease and other degenerative disorders. However, differing from classic Lewy bodies, MA-induced neuronal inclusions appeared as multilamellar bodies resembling autophagic granules. Methamphetamine reproduced this effect in cultured PC12 cells, which offered the advantage of a simple cellular model for the study of the molecular determinants of neuronal inclusions. PC12 inclusions, similar to those observed in nigral neurones, were exclusively localized in the cytoplasm and stained for alpha-synuclein. Time-dependent experiments showed that inclusions underwent a progressive fusion of the external membranes and developed an electrodense core. Inhibition of dopamine synthesis by alpha-methyl-p-tyrosine (alphaMpT), or administering the antioxidant S-apomorphine largely attenuated the formation of inclusions in PC12 cells exposed to MA. Inclusions were again observed when alphaMpT-treated cells were loaded with l-DOPA, which restored intracellular dopamine levels.

Animals↗
PubMedDate not supplied

History of the methamphetamine problem.

Methamphetamine, called meth, crystal, or speed, is a central nervous system stimulant that can be injected, smoked, snorted, or ingested orally; prolonged use at high levels results in dependence. Methamphetamine (MA) is a derivative of amphetamine, which was widely prescribed in the 1950s and 1960s as a medication for depression and obesity, reaching a peak of 31 million prescriptions in the United States in 1967. Until the late 1980s, illicit use and manufacture of MA was endemic to California, but the MA user population has recently broadened in nature and in regional distribution, with increased use occurring in midwestern states. An estimated 4.7 million Americans (2.1% of the U.S. population) have tried MA at some time in their lives. Short- and long-term health effects of MA use include stroke, cardiac arrhythmia, stomach cramps, shaking, anxiety, insomnia, paranoia, hallucinations, and structural changes to the brain. Children of MA abusers are at risk of neglect and abuse, and the use of MA by pregnant women can cause growth retardation, premature birth, and developmental disorders in neonates and enduring cognitive deficits in children. MA-related deaths and admissions to hospital emergency rooms are increasing. Although inpatient hospitalization may be indicated to treat severe cases of long-term MA dependence, optimum treatment for MA abusers relies on an intensive outpatient setting with three to five visits per week of comprehensive counseling for at least the first three months. The burgeoning problems of increased MA use must be addressed by adequate treatment programs suitable for a variety of user types.

Central Nervous System Stimulants↗
PubMedDate not supplied

The CSAT methamphetamine treatment program: research design accommodations for "real world" application.

The Methamphetamine Treatment Program (MTP), funded by the Center for Substance Abuse Treatment, has the objectives of implementing the Matrix outpatient model and evaluating that model in comparison to the existing community "treatments as usual." Seven organizations in three western states (California, Montana, and Hawaii) were selected to participate in this randomized, controlled, multisite project in what constitutes the largest trial to date of treatment for methamphetamine (MA) dependence. One hundred fifty MA-dependent patients recruited at each site are randomly assigned to receive either the Matrix model, a manualized program of intensive outpatient treatment, or the site's standard treatment, "treatment as usual." Participants are evaluated at admission, weekly during treatment, at the time of scheduled discharge, and at six and 12 months after admission. Dependent measures assess changes in drug use, HIV risk behaviors, quality of life, and patient satisfaction. Cost analyses to quantify treatment costs and determine the association between costs and clinical outcomes will be conducted. A number of adjustments in the original study design have been necessitated by the realities of community sites' strengths and limitations. Experiences from this multisite project will also provide a model for other efforts to transfer research-based treatments into community settings. This article describes the main aims of the project, the background and rationale for the study design, a brief description of the research plan, and methods implemented to protect the integrity of the science.

Central Nervous System Stimulants↗
PubMedDate not supplied

Methamphetamine abuse: issues for special populations.

Methamphetamine (MA) abuse has been a problem in the western United States for decades. However, recently the incidence of MA abuse has risen to epidemic levels in some regions and among particular subgroups of the population. Recognizing the need to develop effective treatments for MA dependence, the Center for Substance Abuse Treatment (CSAT) established a multisite Methamphetamine Treatment Program (MTP) that compares the Matrix Model treatment program for MA to the treatments as usual at seven community-based clinics in California, Montana and Hawaii. Examination of the clients receiving services though this project provides an opportunity to explore particular issues of diverse special populations who are impacted by the problem of MA dependence. These groups include rural Americans, Native Americans, Hawaiians, gay and bisexual males and drug court participants. Specifically, this article examines cultural, geographic and situational barriers to accessing and completing treatment and presents strategies that have been used to overcome these barriers.

Bisexuality↗