Treatment with the NMDA antagonist memantine attenuates nociceptive responses to mechanical stimulation in neuropathic rats.
Systemic treatment with the N-methyl-D-aspartate (NMDA) antagonist memantine (MEM) resulted in a decrease in mechanical hyperalgesia and mechanical allodynia in neuropathic rats. Bolus injections of 5, 10 and 20 mg/kg MEM (i.p.) attenuated withdrawal responses following mechanical stimulation for up to 6 h post-injection while saline had no effect. A more remarkable effect was observed following chronic treatment with MEM via mini-osmotic pumps (8 mg/kg per h for 7 days, i.p.), in which nociceptive responses were decreased during treatment and remained depressed for 3 days post-treatment. These antinociceptive effects can be obtained at doses which do not produce motor dysfunction. The results of this study demonstrate that MEM has a therapeutic effect on mechanical hyperalgesia and allodynia and may be considered as an alternative treatment for pathological pain in the clinical setting.
Carlton
S M
SM
Department of Anatomy and Neurosciences, University of Texas Medical Branch, Galveston 77555, USA.
Hargett
G L
GL
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D004343:Drug Implants; D018691:Excitatory Amino Acid Antagonists / Q000008:administration & dosage / Q000494:pharmacology*; D006930:Hyperalgesia / Q000503:physiopathology; D007275:Injections, Intravenous; D008297:Male; D008559:Memantine / Q000008:administration & dosage / Q000494:pharmacology*; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology*; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*
D000700:Analgesics; D004343:Drug Implants; D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D008559:Memantine