Cannabinoid-like Effects Of Five Novel Carboxamide Synthetic Cannabinoids
Synthetic cannabinoids have consistently been shown to produce discriminative stimulus effects similar to those adb butinaca of Δ9-THC (Bannister and Connor, 2018), and MDMB-FUBINACA fully substituted for Δ9-THC (Gamage et al., 2018). The chemical structures of the recent synthetic cannabinoids are unlike that of Δ9-THC, but are largely based on the structure of older synthetic cannabinoids that are known to have substantial abuse liability (Fig. 1). All 5 compounds decreased locomotor activity and produced discriminative stimulus effects similar to those of Δ9-THC, which suggests they may have abuse liability similar to that of Δ9-THC. Subsequent testing identified 5F-ADB to have been present in a total of ten people who had died from unexplained drug overdoses in Japan between September 2014 and December 2014. AMB-FUBINACA produced tremors and may be of increased risk in human recreational users.
Michael B Gatch
These findings are in agreement with earlier studies showing the synthetic cannabinoids substitute for the discriminative stimulus effects of Δ9-THC (see review by Wiley et al., 2017). Pretreatment times and dose ranges for the drug discrimination assay were selected based on the time of peak depression in the locomotor activity assay in mice. As mentioned previously, short-onset compounds have a greater abuse liability; further, compounds that have fewer adverse effects while they are active are likely to be preferred. All five of the compounds in the present study fully substituted with a pretreatment time of 15 min, suggesting a rapid onset of the discriminative stimulus effects. All of the cathinones fully substituted for the discriminative stimulus effects of Δ9-tetrahydrocannabinol (≥80% drug-appropriate responding). Because response suppression may compromise stimulus control, rats failing to complete at least ten responses during the test session were excluded from the analysis of the discriminative stimulus effects of that dose of test compoun
Figure 1.
Each training session lasted a maximum of 10 min, and the rats could earn up to 20 food pellets. Thirty minutes prior to the training sessions, rats received an injection of either vehicle or Δ9-THC and were subsequently placed in the behavior-testing chambers, where food (45-mg food pellets; Bio-Serve, Frenchtown, NJ) was available as a reinforcer for every ten responses (FR10) on a designated injection appropriate lever. A houselight was centered over the hopper close to the ceiling and was illuminated only when the levers were active. Each dose range included doses that were without effect to those producing at least 50% depression compared to vehicle control. Twenty-four male Sprague-Dawley rats were obtained from Envigo (Houston, TX). Male ND4 Swiss–Webster mice were obtained from Envigo (Houston, TX) at approximately 8 weeks of age and maintained in the University of North Texas Health Science Center (UNTHSC) animal facility for two weeks prior to testin
Oxidation of 4′-hydroxybutyl moiety in B2 led to formation of 4′-carboxybutyl metabolite (B4) having a precursor ion of m/z 362, which was 14 Da higher than the m/z for B2 (loss of two hydrogen atoms with addition of a carbonyl group
5F-MDMB-PINACA (also known as 5F-ADB, 5F-ADB-PINACA), MDMB-CHIMICA, MDMB-FUBINACA, ADB-FUBINACA, and AMB-FUBINACA (also known as FUB-AMB, MMB-FUBINACA) were tested for in vivo cannabinoid-like effects to assess their abuse liabilit
These synthetic cannabinoids act directly at cannabinoid CB1 and CB2 receptors as does Δ9-tetrahydrocannabinol (Δ9-THC) found in marijuana, but have different chemical structures unrelated to Δ9-THC, different metabolism, and often greater toxicity (Fantegrossi et al., 2014
A systematic review including data of 114 patients of which the majority was intoxicated due to SCRA smoking revealed that 45 % of the patients who present at the ER after an intoxication due to SCRA smoking recovered within 24 hours
Metabolic Profile of Synthetic Cannabinoids 5F-PB-22, PB-22, XLR-11 and UR-144 by Cunninghamella elegans
This might be due to the low activity of numerous metabolizing enzymes resulting in lower drug biotransformation . HepG2 model detected the major ester hydrolysis metabolite of 4F-MDMB-BINACA in abundance but the rest of the metabolites were found in a small amount. Elegans and HLM models detected all of the in-vivo metabolites (100%), whilst HepG2 cells detected 7 out of the 8 in-vivo metabolites (87.5%). Hence, structural elucidation could not be confirmed unless a reference standard is made availabl
A 30-min period, beginning when maximal depression of locomotor activity first appeared as a function of dose, was used for analysis of dose-response data and calculation of ED50 values. During test sessions, both levers were active, such that ten consecutive responses on either lever led to adb butinaca reinforcement. The substitution tests occurred only if the rats had achieved 85% injection-appropriate responding on the two prior training sessions.
The locomotor activity assay was used to identify approximate time courses and dose ranges of psychoactive effects, which is useful for identifying parameters for drug discrimination experiments and are also predictive of the time course of the psychoactive effects in human users. The purpose of the present study was to assess the abuse liability of 5F-MDMB-PINACA, MDMB-CHIMICA, MDMB-FUBINACA, ADB-FUBINACA, and AMB-FUBINACA. Since there is currently no robust measure of the reinforcing/rewarding effects of cannabinoids, drug discrimination is currently the best model for assessing abuse liability of cannabinoids. The findings produce an apparent paradox, since CPP and self-administration predict with high reliability the likelihood that a compound will be abused by humans, and cannabinoids are well-known to produce active drug-seeking in human