Some mice showed abnormal behaviors (catalepsy, loss of traction, convulsion) right after the administration of the tested substances. The locomotor activity of the mice was measured 30 min and 2 hrs after the last substance administration. We also examined their neurotoxicity using brain samples through histopathological diagnose, especially in the nucleus accumbens core region. In histopathological analysis, neural cells of the animals treated with the high dose (5 mg/kg) of JWH-081 or JWH-210 showed distorted nuclei and nucleus membranes in the core shell of nucleus accumbens, suggesting neurotoxicity.
Table of Conten
After the incubation, mixture was centrifuged (18,000 x g, 20 °C) for 5 min and 0.5 μL of the supernatant was directly injected to the chromatographic system. In the next step, ammonium formate as salting agent was added to the mixture and incubated in a thermomixer (20 °C, 1200 rpm) for 15 min. After vortex-mixing, the mixture was allowed to stand adb butinaca at room temperature for 5 min. MS/MS experiments were performed in MRM (multiple reaction monitoring) mode with an isolation window of 0.4 m/z. The MS measurement was performed in positive ion mode (except for some acidic compounds such as barbiturates
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
Inclusion in an NLM database does not imply endorsement of, or agreement with, the contents by NLM or the National Institutes of Health. It is illegal to sell, distribute, supply, transport or trade the pharmaceutical drug under the Psychoactive Substances Act 2016. The corresponding indole core analogue, 4F-MDMB-BICA (4F-MDMB-BUTICA), has also been widely sold as a designer drug by chemical providers on the internet, first being identified in May 2020. It has been used as an active ingredient in synthetic cannabis products and sold as a designer drug since late 2018. 4F-MDMB-BINACA (also known as MDMB-4F-BINACA using systematic EMCDDA nomenclature or 4F-MDMB-BUTINACA) is an indazole-based synthetic cannabinoid from the indazole-3-carboxamide family.
Fig.
In general, the locomotor depressant and discriminative stimulus effects
adb butinaca have been observed at doses that do not produce adverse effects, although tremors were observed upon handling in mice that received JWH-210 (Gatch et al., 2016), and 5F-AMB produced sustained vocalization and convulsions in rats (Gatch et al., 2018). All of the synthetic cannabinoids tested in the present study fully substituted for the discriminative stimulus effects of Δ9-THC. Subsequently, a one-way analysis of variance was conducted on horizontal activity counts for the 30-min period of maximal effect, and planned comparisons were conducted for each dose against the vehicle control using single degree-of-freedom F tests. A two-way analysis of variance, with dose as a between groups factor and time as a within subject factor, was conducted on horizontal activity counts/10 min interval.
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