Biomaterial Database

N-methyl-D-aspartate (NMDA)-mediated muscle relaxant action of dextromethorphan in rats. 1993

F Block, and M Schwarz

Dept. of Neurology, University of Essen, Germany.

The present study examined whether the antitussive agent dextromethorphan, which is an antagonist at the N-methyl-D-aspartate (NMDA) receptor, depresses spinal reflexes in rats. Injection of both the specific NMDA antagonist (-)-2-amino-7-phosphonoheptanoate and of dextromethorphan dose-dependently reduced the magnitude of the polysynaptic flexor reflex without affecting the monosynaptic H-reflex. In contrast, the non-NMDA antagonist 6,7-dinitroquinoxaline-2,3-dione depressed the H-reflex in a dose-dependent manner without affecting the flexor reflex. The depressant effect of dextromethorphan on the flexor reflex was prevented by co-administration with NMDA but not with the non-NMDA agonist alpha-amino-3-hydroxy-5-terthyl-4-isoxazole-propionic acid. These data suggest that dextromethorphan exerts a muscle relaxant action via the NMDA receptor.

UI	MeSH Term	Description	Entries
D007274	Injections, Intraperitoneal	Forceful administration into the peritoneal cavity of liquid medication, nutrient, or other fluid through a hollow needle piercing the abdominal wall.	Intraperitoneal Injections,Injection, Intraperitoneal,Intraperitoneal Injection
D007278	Injections, Spinal	Introduction of therapeutic agents into the spinal region using a needle and syringe.	Injections, Intraspinal,Injections, Intrathecal,Intraspinal Injections,Intrathecal Injections,Spinal Injections,Injection, Intraspinal,Injection, Intrathecal,Injection, Spinal,Intraspinal Injection,Intrathecal Injection,Spinal Injection
D008297	Male		Males
D009126	Muscle Relaxation	That phase of a muscle twitch during which a muscle returns to a resting position.	Muscle Relaxations,Relaxation, Muscle,Relaxations, Muscle
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D011810	Quinoxalines		Quinoxaline
D012026	Reflex, Stretch	Reflex contraction of a muscle in response to stretching, which stimulates muscle proprioceptors.	Reflex, Tendon,Stretch Reflex,Tendon Reflex
D003915	Dextromethorphan	Methyl analog of DEXTRORPHAN that shows high affinity binding to several regions of the brain, including the medullary cough center. This compound is an NMDA receptor antagonist (RECEPTORS, N-METHYL-D-ASPARTATE) and acts as a non-competitive channel blocker. It is one of the widely used ANTITUSSIVES, and is also used to study the involvement of glutamate receptors in neurotoxicity.	d-Methorphan,Delsym,Dextromethorphan Hydrobromide,Dextromethorphan Hydrobromide, (+-)-Isomer,Dextromethorphan Hydrobromide, Monohydrate,Dextromethorphan Hydrochloride,Dextromethorphan, (+-)-Isomer,Racemethorphan,Hydrobromide, Dextromethorphan,Hydrochloride, Dextromethorphan
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies