methylone and monomethylpropion

Synthetic cathinones display overlapping behavioral effects with psychostimulants (e.g., methamphetamine [MA]) and/or entactogens (e.g., 3,4-methylenedioxymethaphetamine [MDMA])-presumably reflecting their dopaminergic and/or serotonergic activity. The discriminative stimulus effects of MDMA thought to be mediated by such activity have been well characterized in rodents but have not been fully examined in nonhuman primates.. The present studies were conducted to systematically evaluate the discriminative stimulus effects of 5 abused synthetic cathinones (methylenedioxypyrovalerone [MDPV], α-pyrrolidinovalerophenone [α-PVP], methcathinone [MCAT], mephedrone, and methylone) in adult male squirrel monkeys trained to distinguish intramuscular injections of MA (0.1 mg/kg; n = 4) or MDMA (0.6 mg/kg; n = 4) from vehicle.. Each training drug produced dose-dependent effects and, at the highest dose, full substitution. MDMA produced predominantly vehicle-like responding in the MA-trained group, whereas the highest dose of MA (0.56 mg/kg) produced partial substitution (approximately 90% appropriate lever responding in one-half of the subjects) in the MDMA-trained group. MDPV, α-PVP, and MCAT produced full substitution in MA-trained subjects, but, at the same or higher doses, only substituted for MDMA in one-half of the subjects, consistent with primarily dopaminergically mediated interoceptive effects. In contrast, mephedrone and methylone fully substituted in MDMA-trained subjects but failed to fully substitute for the training drug in MA-trained subjects, suggesting a primary role for serotonergic actions in their interoceptive effects.. These findings suggest that differences in the interoceptive effects of synthetic cathinones in nonhuman primates reflect differing compositions of monoaminergic actions that also may mediate their subjective effects in humans.

Topics: Alkaloids; Animals; Behavior, Animal; Benzodioxoles; Central Nervous System Stimulants; Discrimination Learning; Interoception; Male; Methamphetamine; N-Methyl-3,4-methylenedioxyamphetamine; Propiophenones; Psychotropic Drugs; Pyrrolidines; Saimiri; Synthetic Cathinone

Workplace drug testing in Australia is usually adherent to one of two standards, AS/NZS 4308:2008 for urine or AS 4760:2006 for oral fluid. These standards prescribe the drugs tested, devices used and testing methodology followed by the testing agency. However, they are not comprehensive and for many years workers have been able to consume novel psychoactive substances to avoid detection and without consequences. Here, we present a validated method for the detection of 32 Synthetic Stimulant and Hallucogenic drugs, commonly sold as bath salts, in oral fluid. These drugs are cathinone, ephedrone, methylone, flephedrone, MDA, PMA, methedrone, TMA, MDMA, butylone, mephedrone, MDEA, MEC, pentedrone, MBDB, MTA, Alpha-PVP, MPBP, 2C-B, MDPV, DOB, 2C-T-2, TFMPP, DOET, 2C-T-7, naphyrone, MDAI, FMA, DMA, 25C-NBOMe, 25B-NBOMe and 25T4-NBOMe. Sample preparation was undertaken using a simple protein precipitation in acetonitrile. Chromatographic separation was achieved in 7.5 min on a Kinetex F5 column (50 mm × 3 mm × 2.6 μm) using 0.1% formic acid in water and acetonitrile as the mobile phases. The method was validated with limit of detection (1 ng/mL), limit of quantitation (2.5 ng/mL), selectivity, linearity (2.5-500 ng/mL), accuracy (85.3-108.4% of the target concentration) and precision (1.9-14%). This method was applied to 12 samples previously submitted for routine testing and two were found to contain 2-CB and DOB (5 and 4 ng/mL) and, MPBP and TFMPP (both at 4 ng/mL). This method provides for the rapid detection of a large number of compounds in oral fluid which is readily applicable to routine testing laboratories.

Topics: Alkaloids; Anisoles; Australia; Benzylamines; Dimethoxyphenylethylamine; Humans; Illicit Drugs; Methamphetamine; Pentanones; Phenethylamines; Propiophenones; Psychotropic Drugs; Pyrrolidines; Saliva; Substance Abuse Detection

Synthetic cathinones are beta-ketone amphetamine analogs that have emerged as a heterogeneous class of abused compounds that function as either monoamine transporter substrates or inhibitors. Pre-clinical drug discrimination procedures are useful for interrogating structure-activity relationships of abuse-related drug effects; however, in vivo structure-activity relationship comparisons between synthetic cathinones with different mechanisms of action are lacking. The aim of the present study was to determine whether the cocaine-like discriminative stimulus effects of the monoamine transporter inhibitor alpha-pyrrolidinovalerophenone (alpha-PVP) and the monoamine transporter substrate methcathinone were differentially sensitive to 3,4-methylenedioxy and 4-methyl substitutions. Male rhesus monkeys (n = 4) were trained to discriminate intramuscular cocaine (0.32 mg/kg) from saline in a two-key food-reinforced discrimination procedure. Potency and timecourse of cocaine-like discriminative stimulus effects were determined for (±)-alpha-PVP, (±)-methcathinone and their 3,4-methylenedioxy or 4-methyl analogs. Alpha-PVP and methcathinone produced dose- and time-dependent cocaine-like effects. A 3,4-methylenedioxy addition to either alpha-PVP or methcathinone (methylone) did not alter the potency or efficacy to produce cocaine-like effects, but did prolong the time course. A 4-methyl addition to alpha-PVP (pyrovalerone) did not alter the potency or efficacy to produce cocaine-like effects, but did prolong the time course. In contrast, addition of a 4-methyl moiety to methcathinone (4MMC; mephedrone) significantly attenuated efficacy to produce cocaine-like effects. Overall, these results suggest different structural requirements for cocaine-like discriminative stimulus effects of monoamine transporter inhibitor and substrate synthetic cathinone analogs. Given that 4MMC is more hydrophobic than MDMC, these results suggest that hydrophobicity may be an important determinant for limiting monoamine transporter substrate abuse-related behavioral effects.

Topics: Animals; Central Nervous System Stimulants; Cocaine; Conditioning, Operant; Discrimination Learning; Dopamine Uptake Inhibitors; Injections, Intramuscular; Macaca mulatta; Male; Methamphetamine; Propiophenones; Pyrrolidines; Reinforcement, Psychology

Abuse of synthetic cathinones, popularized as "bath salts," has increased dramatically in the USA since their debut in 2010. Preclinical behavioral studies may clarify determinants of the abuse-related effects produced by these compounds.. This study examined behavioral effects of (±)-methcathinone, (±)-3,4-methylenedioxypyrovalerone (MDPV), (±)-3,4-methylenedioxymethcathinone (methylone), and (±)-4-methylmethcathinone (mephedrone) in rats using intracranial self-stimulation (ICSS).. Male Sprague-Dawley rats (n = 18) with electrodes targeting the medial forebrain bundle responded for multiple frequencies of brain stimulation and were tested in two phases. First, dose-effect curves for methcathinone (0.1-1.0 mg/kg), MDPV (0.32-3.2 mg/kg), methylone (1.0-10 mg/kg), and mephedrone (1.0-10 mg/kg) were determined. Second, time courses were determined for effects produced by the highest dose of each compound.. Methcathinone produced dose- and time-dependent facilitation of ICSS. MDPV, methylone, and mephedrone produced dose- and time-dependent increases in low rates of ICSS maintained by low brain stimulation frequencies, but also produced abuse-limiting depression of high ICSS rates maintained by high brain stimulation frequencies. Efficacies to facilitate ICSS were methcathinone ≥ MDPV ≥ methylone > mephedrone. Methcathinone was the most potent compound, and MDPV was the longest acting compound.. All compounds facilitated ICSS at some doses and pretreatment times, which is consistent with abuse liability for each of these compounds. However, efficacies of compounds to facilitate ICSS varied, with methcathinone displaying the highest efficacy and mephedrone displaying the lowest efficacy to facilitate ICSS.

Topics: Animals; Benzodioxoles; Brain; Conditioning, Operant; Data Interpretation, Statistical; Designer Drugs; Dose-Response Relationship, Drug; Electric Stimulation; Injections; Male; Methamphetamine; Propiophenones; Pyrrolidines; Rats; Rats, Sprague-Dawley; Self Administration; Self Stimulation; Substance-Related Disorders; Synthetic Cathinone

The disposition into hair of methylone and other new designer drugs, methcathinone and MBDB, was studied with the animal model. Moreover, the incorporation rates of these drugs were compared with those of their related eight compounds previously studied in order to evaluate their incorporation tendency into hair and the usefulness of hair specimens for the retrospective confirmation of the use of these drugs. When the ratio of hair concentration to AUC in plasma ([Hair]/AUC) was represented as an index of the incorporation rate of drugs into hair, the [Hair]/AUC of methylone was 14 times higher than that of methcathinone. It might support earlier findings that the methylenedioxy group on the benzene ring leads to considerably higher incorporation rates. However, [Hair]/AUC of methylone was five-sevenths times lower in comparison with that of MDMA. This suggested that the beta-carbonyl group leads to lower incorporation rates. Although methylone has both groups in its structure, the positive effect of the methylenedioxy group may be stronger than the negative effect of the beta-carbonyl group. On the other hand, the [Hair]/AUC of MBDB, which has methylenedioxyphenyl-2-butanamine structure, was higher than that of MDMA while that of methcathinone, having beta-ketone in its structure, was extremely low. In conclusion, as with MA and MDMA, the incorporation tendency of methylone and MBDB (except for methcathinone) into hair is relatively high, and a hair sample would be a good specimen for the confirmation of retrospective use of these drugs.

Topics: 3,4-Methylenedioxyamphetamine; Animals; Gas Chromatography-Mass Spectrometry; Hair; Methamphetamine; Models, Animal; Propiophenones; Rats

The urinary metabolites of methylone in humans and rats were investigated by analysing urine specimens from its abuser and after administrating to rats with gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS), using authentic standards. The time-course excretion profiles of methylone and its three metabolites in rats were further investigated after a single intraperitoneal dosing of 5 mg kg-1 methylone hydrochloride. Two major metabolic pathways were revealed for both humans and rats as follows: (1) side-chain degradation by N-demethylation to the corresponding primary amine methylenedioxycathinone (MDC), partly conjugated; and (2) demethylenation followed by O-methylation of either a 3- or 4-OH group on the benzene ring to produce 4-hydroxy-3-methoxymethcathinone (HMMC) or 3-hydroxy-4-methoxymethcathinone (3-OH-4-MeO-MC), respectively, mostly conjugated. Of these metabolites, HMMC was the most abundant in humans and rats. The cumulative amount of urinary HMMC excreted within the first 48 h in rats was approximately 26% of the dose, and the amount of the parent methylone was not more than 3%. These results demonstrate that the analysis of HMMC will be indispensable for proof of the use of methylone in forensic urinalysis.

Topics: Adult; Animals; Chromatography, Gas; Chromatography, Liquid; Designer Drugs; Humans; Male; Mass Spectrometry; Methamphetamine; Models, Biological; Molecular Structure; Propiophenones; Rats; Rats, Wistar; Substance Abuse Detection

Methcathinone and methylone, the beta-ketone analogues of methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA), respectively, were tested for neurotransmitter uptake inhibition in vitro. The beta-ketones were threefold less potent than the nonketo drugs at inhibiting platelet serotonin accumulation, with IC(50)'s of 34.6+/-4.8 microM and 5.8+/-0.7 microM, respectively. Methcathinone and methylone were similar in potency to methamphetamine and MDMA at catecholamine transporters individually expressed in transfected glial cells. For dopamine uptake, IC(50)'s were 0.36+/-0.06 microM and 0.82+/-0.17 microM, respectively; for noradrenaline uptake, IC(50) values were 0.51+/-0.10 microM and 1. 2+/-0.1 microM, respectively. In chromaffin granules, IC(50)'s for serotonin accumulation were 112+/-8.0 microM for methcathinone and 166+/-12 microM for methylone, 10-fold higher than the respective values for methamphetamine and MDMA. Our results indicate that methcathinone and methylone potently inhibit plasma membrane catecholamine transporters but only weakly inhibit the vesicle transporter.

Topics: 3,4-Methylenedioxyamphetamine; Animals; Cattle; Cell Membrane; Chromaffin Cells; Dopamine; Dopamine Uptake Inhibitors; Humans; Membrane Glycoproteins; Membrane Transport Proteins; Methamphetamine; Neuropeptides; Norepinephrine; Propiophenones; Serotonin; Tritium; Tumor Cells, Cultured; Vesicular Biogenic Amine Transport Proteins