Effects of intrathecal ouabain and tizanidine injection for treatment of neuropathic pain in rats.
- Author:
Han-dong OU-YANG
1
;
Wei-an ZENG
;
Qiang LI
;
Wei-xiong HE
;
Pei-zong WANG
;
Li-ling LIN
;
Zhi-quan ZHANG
;
Xian-guo LIU
Author Information
- Publication Type:Journal Article
- MeSH: Analgesics; administration & dosage; Animals; Clonidine; administration & dosage; analogs & derivatives; Injections, Spinal; Ouabain; administration & dosage; Pain; drug therapy; Random Allocation; Rats; Rats, Sprague-Dawley; Spinal Nerves; injuries
- From: Journal of Southern Medical University 2008;28(10):1760-1763
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the effects of intrathecal ouabain and tizanidine injection for treatment of neuropathic pain in rats.
METHODSMale SD rats weighing 250-300 g were randomly divided into 5 groups (n = 6), namely the control group, ouabain group, tizanidine group, combined ouabain and tizanidine injection group, and the antagonist group. Intrathecal catheter was implanted 7 days before spinal nerve ligation to establish the neuropathic pain model. Mechanical withdrawal threshold (MWT) before and after intrathecal administration of the agents was recorded in the rats. Isobolographic analysis was performed to evaluate the interactions between the agents.
RESULTSIntrathecal injection of ouabain (0.25-5 microg) or tizanidine (0.5-5 microg) alone produced dose-dependent analgesic effect against the neuropathic pain (P < 0.05). Isobolographic analysis revealed a synergistic interaction between ouabain and tizanidine. Intrathecal pretreatment with atropine (5 microg) or yohimbine (20 microg) antagonized the effects of ouabain and tizanidine administered alone or in combination (P < 0.05).
CONCLUSIONIntathecal injection of ouabain or tizanidine produces dose-dependent analgesic effects against neuropathic pain, and their synergistic effect after combined injection probably involves the cholinergic transmission and alpha2 receptor.
