RESUMO
Methcathinone (MCAT) belongs to the designer drugs called synthetic cathinones, which are abused worldwide for recreational purposes. It has strong stimulant effects, including enhanced euphoria, sensation, alertness, and empathy. However, little is known about how MCAT modulates neuronal activity in vivo. Here, we evaluated the effect of MCAT on neuronal activity with a series of functional approaches. C-Fos immunostaining showed that MCAT increased the number of activated neurons by 6-fold, especially in sensory and motor cortices, striatum, and midbrain motor nuclei. In vivo single-unit recording and two-photon Ca2+ imaging revealed that a large proportion of neurons increased spiking activity upon MCAT administration. Notably, MCAT induced a strong de-correlation of population activity and increased trial-to-trial reliability, specifically during a natural movie stimulus. It improved the information-processing efficiency by enhancing the single-neuron coding capacity, suggesting a cortical network mechanism of the enhanced perception produced by psychoactive stimulants.
Assuntos
Camundongos , Animais , Reprodutibilidade dos Testes , Neurônios , Sensação , PercepçãoRESUMO
Methcathinone, a new cathinone designer drug, which is structurally similar to amphetamine analogs, is a central nervous stimulant.Recently, there has been a worldwide rise in its popularity and abuse, and a growing number of cases with disability or even death is reported in several countries, resulting in public concern.The typical symptoms include accelerated heartbeat, high temperature, anxiety, depression, etc.Forensic studies on its toxicity mechanism are rare.This article reviews its toxicological effects, poisoning symptoms, poisoning and addiction mechanisms, and detection methods, to provide theoretical reference for future studies and guidance for related forensic identification.
RESUMO
Objective To propose an alternative solid phase extraction-gas chromatography-mass spectrometry (SPE-GC-MS) method for the sensitive determination of cathinones in human urine samples, plus methodological verification.Methods Human urine samples were concentrated by solid phase extraction (SPE) sorbent and converted into the corresponding heptafluorobutyric acid anhydride derivatives.Methcathinone, 4-methyl methcathinone and 3, 4-methylenedioxy-N-methylcathinone were detected by gas chromatography-mass spectrometry (GC-MS).With quantitative analysis by internal standard method, methodological verification was carried out from the aspects of specificity, precision and recovery rate.Results Methcathinone, 4-methyl methcathinone and 3, 4-methylenedioxy-N-methylcathinone showed good linearly in the range of 25-200 ng/mL of urine (r＞0.99), with the limits of detection2.0 ng/mL, limit of quantitation 25.0 ng/mL, both intra-and inter-day coefficients of variation lower than 6.0％, and recovery rates of 98.4％-105.7％.Conclusion The proposed SPE-GC-MS procedure has good accuracy and specificity, can meet the need of qualitative and quantitative analysis of cathinones in the urine of drug abusers, and therefore provide technical support for the detection of cathinone abuse.
RESUMO
Objective To establish a method for the analysis of methcathinone in urine by gas chromatography-mass spectrometry (GC-MS).Methods Proadifen hydrochloride (internal standard) and buffer solution (pH=9) were added into the urine samples,and methcathinone was extracted by ethyl acetate.The extract was volatilized in 50 ℃ nitrogen gas flow and the remnant was dissolved by methanol and analysed by GC-MS.Results The methcathinone in urine showed a good linear relationship in the mass concentration range of 0.02-2.00 μg/mL.The linear equation was y=0.301 9x+0.0189 (r=0.9992),and the detection limit was 0.01 μg/mL.The recoveries of methcathinone in urine was 96.4％-99.2％,with the intraday precision of 5.8％-7.6％ and the inter-day precision of 6.0％-8.1％.Conclusion The method is convenient and sensitive,which can be applied to the forensic identification of methcathinone in urine.