Neurotoxicology Research Group, Division Toxicology, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands. Electronic address: r.westerink@uu.nl.
2 papers in the library · 64 citations · publishing 2018-2019
All eight new psychoactive substances (PMMA, α-PVP, methylone, MDPV, 2C-B, 25B-NBOMe, BZP, TFMPP) and two classic illicit drugs (cocaine, methamphetamine) rapidly and concentration-dependently decreased the weighted mean firing rate and weighted mean burst rate of rat primary cortical cultures grown on multi-well microelectrode arrays during a 30-minute acute exposure. Cocaine most potently inhibited firing (IC50 9.8 μM), while methamphetamine and PMMA were much less potent (IC50 100 μM and 112 μM). Among cathinones, MDPV and α-PVP had comparable IC50 values (29 μM and 21 μM), but methylone was 10-fold less potent (IC50 235 μM).
The effects of several new psychoactive substances (NPS) and illicit drugs on neuronal activity were tested in rat brain cells grown on microelectrode arrays. After 30 minutes of exposure, all compounds reduced neuronal activity in a dose-dependent manner. Extending exposure to 5 hours did not cause further decreases. After a 19-hour washout period, activity fully recovered only for methamphetamine, cocaine, and benzylpiperazine; partially recovered for MDMA, PMMA, and α-PVP; and did not recover at the highest concentrations of MDPV, 2C-B, 25B-NBOMe, and TFMPP. Low concentrations of methylone and 2C-B actually increased activity after washout. The ability of neural networks to regain activity after drug exposure appears unrelated to drug class or potency. Complete recovery was rare, which is concerning.