Neuropsychopharmacological understanding for therapeutic application of morphinans

Abstract

Morphinans are a class of compounds containing the basic structure of morphine. It is well-known that morphinans possess diverse pharmacological effects on the central nervous system. This review will demonstrate novel neuroprotective effects of several morphinans such as, dextromethorphan, its analogs and naloxone on the models of multiple neurodegenerative disease by modulating glial activation associated with the production of a host of proinflammatory and neurotoxic factors, although dextromethorphan possesses neuropsychotoxic potentials. The neuroprotective effects and the therapeutic potential for the treatment of excitotoxic and inflammatory neurodegenerative diseases, and underlying mechanism of morphinans are discussed.

Fig. 1

Structures of morphine, naloxone, dextromethorphan (DM), and DM analogs

Fig. 2

Metabolic pathway of DM. CYP = cytochrome P450

Fig. 3

Neuropharmacological actions mediated by morphinans