OBJECTIVE: To study the distribution and metabolism of methamphetamine in the hair of guinea pig. METHODS: Determination of methamphetamine and its metabolite amphetamine in hair was performed by GC/MS and GC/NPD. Concentration-time course of methamphetamine and amphetamine in hair of guinea were recorded. Relationship between hair color, administrated dose and drug concentration in hair were also discussed. RESULTS: The concentration of amphetamine is higher than the concentration of methamphetamine in the hair of guinea administrated a single dose or seven doses of methamphetamine. The concentration of methamphetamine and amphetamine were significantly related with administration dose and the incorporation rate into white and brown hair is much poorer than that of black hair. CONCLUSION Administration methods, dose and the color of hair affect the concentration of methamphetamine and amphetamine.
Amphetamine/metabolism* ; Animals ; Guinea Pigs ; Hair/metabolism* ; Hair Color ; Male ; Methamphetamine/metabolism*

OBJECTIVETo investigate whether 3,4-methylenedioxymethamphetamine (MDMA) abuse produces another neurotoxicity which may significantly inhibit the acetylcholinesterase activity and result in severe oxidative damage and liperoxidative damage to MDMA abusers.

METHODS120 MDMA abusers (MA) and 120 healthy volunteers (HV) were enrolled in an independent sample control design, in which the levels of lipoperoxide (LPO) in plasma and erythrocytes as well as the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric methods.

RESULTSCompared with the average values of biochemical parameters in the HV group, those of LPO in plasma and erythrocytes in the MA group were significantly increased (P < 0.0001), while those of SOD, CAT, GPX and AChE in erythrocytes in the MA group were significantly decreased (P < 0.0001). The Pearson product-moment correlation analysis between the values of AChE and biochemical parameters in 120 MDMA abusers showed that significant linear negative correlation was present between the activity of AChE and the levels of LPO in plasma and erythrocytes (P < 0.0005-0.0001), while significant linear positive correlation was observed between the activity of AchE and the activities of SOD, CAT and GPX (P < 0.0001). The reliability analysis for the above biochemical parameters reflecting oxidative and lipoperoxidative damages in MDMA abusers suggested that the reliability coefficient (alpha) was 0.8124, and that the standardized item alpha was 0.9453.

CONCLUSIONThe findings in the present study suggest that MDMA abuse can induce another neurotoxicity that significantly inhibits acetylcholinesterase activity and aggravates a series of free radical chain reactions and oxidative stress in the bodies of MDMA abusers, thereby resulting in severe neural, oxidative and lipoperoxidative damages in MDMA abusers.

Acetylcholinesterase ; metabolism ; Adolescent ; Adult ; Amphetamine-Related Disorders ; blood ; enzymology ; metabolism ; Catalase ; blood ; Cholinesterase Inhibitors ; adverse effects ; urine ; Erythrocytes ; enzymology ; Female ; Humans ; Lipid Peroxidation ; drug effects ; Lipid Peroxides ; blood ; Male ; N-Methyl-3,4-methylenedioxyamphetamine ; adverse effects ; urine ; Oxidative Stress ; drug effects ; Superoxide Dismutase ; blood