Central Effects of the Designer Drug Mephedrone in Mice-Basic Studies.

Anna Serefko,Aleksandra Szopa,Bernadeta Szewczyk,Maria Radziwoń-Zaleska,Ewa Poleszak,Gabriela Bielecka-Papierz,Piotr Skałecki,Sylwia Talarek

doi:10.3390/brainsci12020189

Abstract

Mephedrone belongs to the “party drugs” thanks to its psychostimulant effects, similar to the ones observed after amphetamines. Though mephedrone is used worldwide by humans and in laboratory animals, not all properties of this drug have been discovered yet. Therefore, the main aim of this study was to expand the knowledge about mephedrone’s activity in living organisms. A set of behavioral tests (i.e., measurement of the spontaneous locomotor activity, rotarod, chimney, elevated plus maze with its modification, novel object recognition, and pentylenetetrazol seizure tests) were carried out in male albino Swiss mice. Different dose ranges of mephedrone (0.05–5 mg/kg) were administered. We demonstrated that mephedrone at a dose of 5 mg/kg rapidly increased the spontaneous locomotor activity of the tested mice and its repeated administration led to the development of tolerance to these effects. Mephedrone showed the anxiolytic-like potential and improved spatial memory, but it did not affect recognition memory. Moreover, the drug seemed not to have any anticonvulsant or proconvulsant activity. In conclusion, mephedrone induces many central effects. It easily crosses the blood-brain barrier and peaks in the brain quickly after exposure. Our experiment on inducing a hyperlocomotion effect showed that mephedrone‘s effects are transient and lasted for a relatively short time.

Highlights

Mephedrone belongs to the “party drugs” thanks to its psychostimulant and empathogenic effects [3], similar to the ones observed after administration of cocaine, methamphetamine, and/or 3,4-methylenedioxymethamphetamine (MDMA)
Mephedrone in the Mephedrone given at a dose of mg/kg increased the percentage of entries into the Mephedrone given at a dose of 1 mg/kg increased the percentage of entries into the open arms of the elevated plus maze (EPM) in mice
Kehr et al [20] reported that 20 min after administration of a low mephedrone dose (1 mg/kg), serotonin and dopamine levels in the brain of SpragueDawley rats were significantly increased. Another set of our experiments showed that administration of mephedrone (5 mg/kg) for several days may result in the development of tolerance to the mephedrone-related ambulatory hyperactivity

Summary

Introduction

Mephedrone is one of the most popular synthetic cathinone derivatives used recreationally. Though it was synthesized in 1929, the drug did not receive much interest as a psychoactive agent for many years. 2007, mephedrone was quickly associated with the development of serious adverse reactions, including fatal intoxications, which raised concerns about the safety profile of this cathinone. The substance was banned in the European Union countries and in several other non-European ones, including Israel, Australia, or the USA. It is still illegally sold under different street names

Objectives

Methods

Results

Discussion

Conclusion