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 the mechanism of methamphetamine (METH)-induced toxicity in PC12 cells.

METHODSPC12 cells were treated with METH for 24 h at the doses of 0, 0.5, 1.0, 1.5, 2.0, or 2.5 mmol/L. The morphological changes of the cells were observed under inverted microscope after the treatment. MTT assay and flow cytometry were used to assess the cell viability and apoptotic rates, respectively, and the level of nitric oxide (NO) was measured by enzyme reduction method.

RESULTSThe PC12 cells exposed to METH were morphologically featured by cell shrinkage, dendrite disruption and disappearance of cell reticular formation. METH exposure caused a dose-dependent reduction in the cell viability (P<0.01), resulting in also increased cell apoptotic rate and significant elevation of NO in the cell culture supernatant (P<0.05).

CONCLUSIONMETH exposure induces cytotoxicity and injury of differentiated PC12 cells, leading to decreased cell viability and increased cell apoptosis and NO level. Cell apoptosis and excessive NO production are involved in METH-induced cytotoxicity.

Animals ; Apoptosis ; drug effects ; Cell Survival ; drug effects ; Methamphetamine ; toxicity ; Neurotoxins ; toxicity ; Nitric Oxide ; metabolism ; PC12 Cells ; Rats

OBJECTIVETo study the changes in the microglial cells and the activity of nitric oxide synthase (NOS), inducible nitric oxide synthase (iNOS) and constitutive nitric oxide synthase (cNOS) in the striatum of rats with methamphetamine (METH) treatment.

METHODSThe rats were randomly divided into two groups for injections with METH or saline. Specific antibody against OX-42 was used to detect the changes in the morphology and the number of microglia, and the activities of NOS, iNOS and cNOS were compared between the two groups.

RESULTSThe microglial cells were activated and their number significantly increased in the striatum of rats with METH treatment as compared with those in the saline group. The activated microglial cells showed bushy and amoeboid morphologies in the METH group. METH also significantly enhanced the activities of NOS, iNOS and cNOS in the striatum (P < 0.05).

CONCLUSIONMicroglial activation and increased NOS activity may participate in METH-induced neurotoxicity in rat striatum.

Animals ; Corpus Striatum ; enzymology ; Male ; Methamphetamine ; pharmacology ; Microglia ; metabolism ; Nitric Oxide Synthase ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Random Allocation ; Rats ; Rats, Wistar

This study examined the neuroprotective effect of cluster of differentiation molecule 200 (CD200) against methamphetamine (METH)-induced neurotoxicity. In the in vitro experiment, neuron-microglia cultures were treated with METH (20 μmol/L), METH (20 μmol/L)+CD200-Fc (10 μg/mL) or CD200-Fc (10 μg/mL). Those untreated served as control. Microglia activation expressed as the ratio of MHC-II/CD11b was assessed by flow cytometry. The cytokines (IL-1β, TNF-α) secreted by activated microglia were detected by enzyme-linked immunosorbent assay (ELISA). In the in vivo experiment, 40 SD rats were divided into control, METH, METH+CD200-Fc and CD200-Fc groups at random. Rats were intraperitoneally injected with METH (15 mg/kg 8 times at 12 h interval) in METH group, with METH (administered as the same dose and time as the METH group) and CD200-Fc (1 mg/kg at day 0, 2, 4 after METH injection) in METH+CD200-Fc group, with CD200-Fc (1 mg/kg injected as the same time as the METH+CD200-Fc group) or with physiological saline solution in the control group. The level of striatal dopamine (DA) in rats was measured by high-performance liquid chromatography (HPLC). The microglial cells were immunohistochemically detected for the expression of Iba-1, a marker for microglial activation. The results showed that METH could increase the microglia activation in the neuron-microglia cultures and elevate the secretion of IL-1β and TNF-α, which could be attenuated by CD200-Fc. Moreover, CD200-Fc could partially reverse the striatal DA depletion induced by METH and reduce the number of activated microglia, i.e. Iba-1-positive cells. It was concluded that CD200 may have neuroprotective effects against METH-induced neurotoxicity by inhibiting microglial activation and reversing DA depletion in striatum.
Animals ; Animals, Newborn ; Antigens, CD ; administration & dosage ; Cells, Cultured ; Coculture Techniques ; Corpus Striatum ; cytology ; drug effects ; immunology ; Cytokines ; immunology ; Dopamine ; immunology ; Drug Interactions ; Male ; Methamphetamine ; toxicity ; Microglia ; drug effects ; immunology ; Neurons ; metabolism ; Rats ; Rats, Sprague-Dawley

The basic changes are to transform the levels of many genes' transcriptions and translations when methamphetamine is injected into the organism. Those genes enclose four classes: genes intermediating the damages or death of neurons,genes involving circadian rhythms of activity, genes concerning the abnormality of behaviors and some genes difficult to be classified. The transformations of the transcriptions or translations of these genes cooperate to produce many clinic syndromes of methamphetamine-addictors. Moreover, the study of these genes can provide testimonies to forensic identification.
Animals ; Circadian Rhythm/genetics* ; Forensic Medicine ; Gene Expression Regulation/drug effects* ; Humans ; Methamphetamine/pharmacology* ; Neocortex/metabolism* ; Neurons/pathology* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Proto-Oncogene Proteins c-fos/metabolism* ; Substance-Related Disorders ; Transcription, Genetic/drug effects* ; Translocation, Genetic/drug effects*