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Updated: Aug 18, 2026

The Sciatic Nerve Cuffing Model of Neuropathic Pain in Mice
Published on: July 16, 2014
Medullary N-type and P/Q-type calcium channels contribute to neuropathy-induced allodynia
Mark O Urban1, Kunkun Ren, Marciano Sablad
1Department of Pharmacology, Merck Research Laboratories, San Diego, CA 92121, USA. mark.urban@merck.com
Abstract:
The present study was designed to determine the contribution of N-type, P/Q-type and L-type calcium channels in the rostral ventromedial medulla to tactile allodynia following peripheral nerve injury. L5/L6 spinal nerve ligation in rats produced tactile allodynia, which was dose-dependently inhibited by intrarostral ventromedial medulla microinjection of the N-type calcium channel antagonist omega-conotoxin MVIIA. Similarly, intrarostral ventromedial medulla microinjection of the P/Q-type calcium channel antagonist omega-agatoxin IVA inhibited spinal nerve ligation-induced tactile allodynia, whereas intrarostral ventromedial medulla microinjection of the L-type calcium channel antagonist nimodipine had no effect. These results demonstrate that N-type and P/Q-type calcium channels in the rostral ventromedial medulla contribute to tactile allodynia following peripheral neuropathy, likely via neurotransmitter-mediated activation of descending facilitatory systems from the rostral ventromedial medulla.
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