In vitro and in vivo pharmacological characterization of the synthetic opioid MT-45.

In vitro and in vivo pharmacological characterization of the synthetic opioid MT-45. Neuropharmacology. 2020 Apr 25;:108110 Authors: S B, Neto J A, R A, M T, A G, G S, De-Giorgio F, P F, M N, G C, M M Abstract MT-45 is a synthetic opioid that was developed in the 1970s as an analgesic compound. However, in recent years MT-45 has been associated with multiple deaths in Europe and has been included in the class of novel psychoactive substances known as novel synthetic opioids (NSOs). Little is known about the pharmaco-toxicological effects of MT-45. Therefore, we used a dynamic mass redistribution (DMR) assay to investigate the pharmacodynamic profile of this NSO in vitro compared with morphine. We then used in vivo studies to investigate the effect of the acute systemic administration of MT-45 (0.01-15 mg/kg i.p.) on motor and sensorimotor (visual, acoustic and tactile) responses, mechanical and thermal analgesia, muscle strength and body temperature in CD-1 male mice. Higher doses of MT-45 (6-30 mg/kg i.p.) were used to investigate cardiorespiratory changes (heart rate, respiratory rate, SpO2 saturation and pulse distention). All effects of MT-45 were compared with those of morphine. In vitro DMR assay results demonstrated that at human recombinant opioid receptors MT-45 behaves as a potent selective mu agonist with a slightly higher efficacy than morphine. In vivo results showed that MT-45 progressively induces tail elevation at...
Source: Neuropharmacology - Category: Drugs & Pharmacology Authors: Tags: Neuropharmacology Source Type: research