Natural (∆9-THC) and synthetic (JWH-018) cannabinoids induce seizures by acting through the cannabinoid CB1 receptor

Natural cannabinoids and their synthetic substitutes are the most widely used recreational drugs. Numerous clinical cases describe acute toxic symptoms and neurological consequences following inhalation of the mixture of synthetic cannabinoids known as “Spice.” Here we report that an intraperitoneal administration of the natural cannabinoid Δ9-tetrahydrocannabinol (10 mg/kg), one of the main constituent of marijuana, or the synthetic cannabinoid JWH-018 (2.5 mg/kg) triggered electrographic seizures in mice, recorded by electroencephalography and videography. Administration of JWH-018 (1.5, 2.5 and 5 mg/kg) increased seizure spikes dose-dependently. Pretreatment of mice with AM-251 (5 mg/kg), a cannabinoid receptor 1-selective antagonist, completely prevented cannabinoid-induced seizures. These data imply that abuse of cannabinoids can be dangerous and represents an emerging public health threat. Additionally, our data strongly suggest that AM-251 could be used as a crucial prophylactic therapy for cannabinoid-induced seizures or similar life-threatening conditions

The synthesis and characterization of the 'research chemical' N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(cyclohexylmethyl)-3-(4-fluorophenyl)-1H-pyrazole-5-carboxamide (3,5-AB-CHMFUPPYCA) and differentiation from its 5,3-regioisomer.

This study presents the identification of N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(cyclohexylmethyl)-3-(4-fluorophenyl)-1H-pyrazole-5-carboxamide that was termed 3,5-AB-CHMFUPPYCA. This compound was obtained from a UK-based Internet vendor, who erroneously advertised this 'research chemical' as AZ-037 and which would have been associated with (S)-N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(5-fluoropentyl)-5-(4-fluorophenyl)-1H-pyrazole-3-carboxamide. The presence of the pyrazole core indicates a bioisosteric replacement of an indazole ring that is frequently associated with synthetic cannabinoids of the PINACA, FUBINACA, and CHMINACA series. The pyrazole ring system present in 3,5-AB-CHMFUPPYCA gives rise to the regioisomer N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(cyclohexylmethyl)-5-(4-fluorophenyl)-1H-pyrazole-3-carboxamide (named 5,3-AB-CHMFUPPYCA) and both isomers were synthesized using two specific routes which supported the correct identification of the 'research chemical' as 3,5-AB-CHMFUPPYCA. Both isomers could be conveniently differentiated. Interestingly, a route specific chlorine-containing by-product also was observed during the synthesis of 3,5-AB-CHMFUPPYCA and identified as N-(1-amino-3-methyl-1-oxobutan-2-yl)-4-chloro-1-(cyclohexylmethyl)-3-(4-fluorophenyl)-1H-pyrazole-5-carboxamide. An extensive analytical characterization included chromatographic, spectroscopic, mass spectrometric platforms as well as crystal structure analysis. The syntheses and analytical characterizations of both AB-CHMFUPPYCA isomers are reported for the first time and serves as a reminder that the possibility of mislabeling of 'research chemicals' cannot be excluded. The pharmacological activities of both AB-CHMFUPPYCA isomers remain to be explored. Copyright © 2015 John Wiley & Sons, Ltd

HPLC-UV method development for fentanyl determination in rat plasma and its application to elucidate pharmacokinetic behavior after i.p. administration to rats.

A simple, rapid and validated high performance liquid chromatography method with UV detection for the quantification of an opioid agonist, fentanyl (FEN), in rat plasma was developed. The assay procedure involved chromatographic separation using a ZIC-HILIC SeQUANT column (250 mm × 4.6 mm, i.d., 5 μm) and a mobile phase of acetonitrile and acetate buffer (pH 3.4, 20mM) of ratio (=65:35, v/v) at a flow rate of 1.2 mL/min and detection wavelength of 201 nm. Plasma sample (100 μL) pretreatment was based on simple deprotienization by acetonitrile spiked with clonidine as an internal standard (I.S.) of 20 ng/mL followed by extraction with tert-butyl methyl ether and centrifugation. The organic layer was evaporated under N(2) gas and reconstituted with 100 μL of acetate buffer (pH 3.4, 20mM), and 50-μL portions of reconstituted sample were injected onto the column. Sample analysis including sample pretreatment was achieved within 35 min. Calibration curve was linear (r ≥ 0.998) from 5 to 100 ng/mL. Both intra- and inter-day assay precisions that are presented through RSD were lower than 12.6% for intra-day and lower than 12.0% for inter-day assessment. Limit of detection was 0.8 ng/mL at S/N of 3. This method was omitting the use of expensive solid phase extraction and time consuming liquid extraction procedures. Moreover, the present method was successfully applied to study pharmacokinetic parameters of FEN after intraperitoneal administration to male Wistar rat. Pharmacokinetic parameters estimated by using moment analysis were T(1/2) 198.3 ± 44.7 min, T(max) 28.3 ± 2.9 min and AUC(0-180) 15.6 ± 2.9(× 10(2))ngmin/mL

HPLC determination of methylphenidate and its metabolite, ritalinic acid, by high-performance liquid chromatography with peroxyoxalate chemiluminescence detection.

An HPLC-peroxyoxalate chemiluminescence (PO-CL) method for simultaneous determination of methylphenidate (MPH) and ritalinic acid (RA) was developed. The method was used to monitor MPH and RA after administration of MPH to rats. Deproteinized plasma spiked with 1-(3-trifluoromethylphenyl)piperazine (IS) was dried and labeled with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F). The labeled sample was cleaned with two kinds of solid-phase extraction cartridge, and the DBD-labels were separated on an ODS column with gradient elution using a mixture of CH(3)CN and imidazole-HNO(3) buffer. Separation of MPH and RA can be achieved within 33 min. The LODs of MPH and RA at a signal-to-noise ratio of 3 were 2.2 and 0.4 ng mL(-1), respectively. Moreover, monitoring of MPH and RA after MPH administration (10 mg kg(-1)) to rat could be performed. The concentration of RA 480 min after administration was eight times higher than that of MPH. The proposed HPLC-PO-CL method was useful for determination of MPH and RA in rat plasma and was successfully used to monitor these substances after MPH administration

User Experiences of Development of Dependence on the Synthetic Cannabinoids, 5f-AKB48 and 5F-PB-22, and Subsequent Withdrawal Syndromes

Emergence of synthetic cannabinoids (SCBs) in herbal smoking mixtures is a public health concern. New SCB’s such as 5f-AKB48 and 5F-PB-22 have been detected in French seizures and in sudden death post mortems in the US. The aim was to describe development of dependence on herbal smoking mixtures containing the SCB’s, 5f-AKB48 and 5F-PB-22 and subsequent withdrawal syndromes. Dependent users of herbal smoking mixtures known to contain the SCB’s 5f-AKB48 and 5F-PB-22 with an average Severity of Dependence Score (SDS) of 13 were interviewed using a structured guide (three males/three females). Narratives were analysed using the Empirical Phenomenological Psychological (EPP) five step method. Six themes with 68 categories emerged from the analysis. Themes are illustrated as 1) Networks and Product Availability; 2) Drivers and Motives for Use; 3) Effect and Pathways toward Dependence; 4) Poly Substance Use and Comparisons to Natural Cannabis; 5) Dependence and Withdrawal and 6) Self-detoxification Attempts. Two higher levels of abstraction above these theme-levels emerged from the data, with sole use of herbal smoking mixtures containing 5f-AKB48 and 5F-PB-22 centering on the interplay between intense cravings, compulsive all-consuming seeking, use and re-dose behaviours, and fear of the psychiatric and self-harms caused when in withdrawal. This is the first study describing dependence and withdrawal experiences in users dependent on 5f-AKB48 and 5F-PB-22. Given the potential for adverse psychiatric and physical consequences of dependent use, further development of specific clinical responses and clinical research around toxicity and withdrawal severity are warranted

An overview of recent developments in the analytical detection of new psychoactive substances (NPSs)

New psychoactive substances (NPSs), sometimes referred to as “legal highs” in more colloquial environments/ the media, are a class of compounds that have been recently made available for abuse (not necessarily recently discovered) which provide similar effects to the traditional well studied illegal drugs but are not always controlled under existing local, regional or international drug legislation. Following an unprecedented increase in the number of NPSs in the last 5 years (with 101 substances discovered for the first time in 2014 alone) its, occasionally fatal, consequences have been extensively reported in the media. Such NPSs are typically marketed as ‘not for human consumption’ and are instead labelled and sold as plant food, bath salts as well as a whole host of other equally nondescript aliases in order to bypass legislative controls. NPSs are a new multi-disciplinary research field with the main emphasis in terms of forensic identification due to their adverse health effects, which can range from minimal to life threatening and even fatalities. In this mini-review we overview this recent emerging research area of NPSs and the analytical approaches reported to provide detection strategies as well as detailing recent reports towards providing point-of-care/in-the-field NPS (“legal high”) sensors