Neuropathic pain behavior in rats depends on the afferent input from nerve-end neuroma including histamine-sensitive C-fibers.
Sciatic and saphenous neurectomy in rats produces nerve-end neuromas, known to be a source of afferent input. Concurrently rats self-injure the denervated hindpaw ('autotomy'), a behavior related to neuropathic pain in humans. Here we show that surgical resection of the neuromas in various groups of rats, each at a different postoperative time (days 22, 33, 48) suppress autotomy. This recalls the pain relief in humans following resection of painful neuromas. We also show that daily injections of astemizole, a peripheral anti-histamine which blocks histamine H1-receptors, suppress autotomy. Since mostly C-fibers in rat neuroma are sensitive to histamine, these results corroborate the suggestion that autotomy is driven by afferent neuroma input, mainly in histamine-sensitive C-fibers.
Seltzer
Z
Z
Physiology Branch, Faculty of Dental Medicine, Jerusalem, Israel.
Paran
Y
Y
Eisen
A
A
Ginzburg
R
R
D000818:Animals; D016589:Astemizole / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects*; D006632:Histamine / Q000494:pharmacology; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D008297:Male; D009411:Nerve Endings / Q000503:physiopathology*; D009412:Nerve Fibers / Q000502:physiology; D009423:Nervous System Neoplasms / Q000503:physiopathology*; D009463:Neuroma / Q000503:physiopathology*; D009475:Neurons, Afferent / Q000502:physiology*; D010146:Pain / Q000523:psychology*; D051381:Rats; D011919:Rats, Inbred Strains; D012584:Sciatic Nerve / Q000502:physiology
D006634:Histamine H1 Antagonists; D016589:Astemizole; D006632:Histamine