Neuropathic pain sensations are differentially sensitive to dextrorphan.
Rats with an experimental painful peripheral neuropathy (the CCI model) display heat-hyperalgesia and mechanoallodynia. Previous work has shown that the heat-hyperalgesia is suppressed by dextrorphan (DEX) and other N-methyl-D-aspartate (NMDA) receptor antagonists. The present work shows that when tested in the same rats, a dose of DEX that is maximally effective against heat-hyperalgesia has no effect on mechano-allodynia. The results suggest that different kinds of abnormal pain sensations may be caused by different pathophysiologic mechanisms that may respond differently to drug therapy.
Tal
M
M
Department of Anatomy, Hebrew University-Hadassah Dental and Medical School, Jerusalem, Israel.
Bennett
G J
GJ
D000818:Animals; D003917:Dextrorphan / Q000494:pharmacology*; D006358:Hot Temperature; D006930:Hyperalgesia / Q000503:physiopathology; D008297:Male; D010146:Pain / Q000503:physiopathology*; D010523:Peripheral Nervous System Diseases / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D012584:Sciatic Nerve / Q000187:drug effects / Q000502:physiology / Q000503:physiopathology
D016194:Receptors, N-Methyl-D-Aspartate; D003917:Dextrorphan