title: Antinociceptive effect of intrathecal administration of taurine in rat models of neuropathic pain.
abstract: OBJECTIVE
  Taurine is the most abundant amino acid in many tissues. Although taurine has been shown to be antinociceptive, in this report, our focus is to elucidate the mechanism and action site on neuropathic pain. This study used behavioural assessments to determine whether taurine attenuates neuropathic pain in the spinal cord.
  
  
  METHODS
  Chronic constriction injury (CCI) to the sciatic nerve and streptozotocin-induced diabetic neuropathy were introduced to male Sprague-Dawley rats. We then assessed the antinociceptive effect of spinal injections of taurine (100, 200, 400, or 800 μg) using electronic von Frey, paw pressure, and plantar tests. To explore the effect of taurine on motor function, a rotarod test was performed, and in order to determine which neurotransmitter pathway is involved in taurine's action, we examined how several antagonists of spinal pain processing receptors altered the effect of taurine 400 μg in a paw pressure test.
  
  
  RESULTS
  Taurine alleviated mechanical allodynia, mechanical hyperalgesia, and thermal hyperalgesia in CCI rats and suppressed mechanical allodynia and hyperalgesia in diabetic rats. Significant effects were observed at 200 μg in both models. On the other hand, taurine dose-dependently affected motor performance, and a significant effect was seen at 400 μg. The antinociceptive effects were reversed completely by pretreatment with an intrathecal injection of strychnine, a glycine receptor antagonist.
  
  
  CONCLUSIONS
  The present study demonstrated that intrathecal administration of taurine attenuates different models of neuropathic pain, and these effects seem to be mediated by the activation of glycinergic neurotransmission. These findings suggest that taurine may be a candidate remedy for neuropathic pain.
authors.affiliation: Department of Anesthesiology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu, 807-8555, Japan.
authors.forename: Tadanori
authors.initials: T
authors.lastname: Terada
authors.affiliation: Department of Anesthesiology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu, 807-8555, Japan. kojihara@med.uoeh-u.ac.jp.
authors.forename: Koji
authors.initials: K
authors.lastname: Hara
authors.affiliation: Department of Anesthesiology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu, 807-8555, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Haranishi
authors.affiliation: Department of Anesthesiology, University of Occupational and Environmental Health, School of Medicine, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu, 807-8555, Japan.
authors.forename: Takeyoshi
authors.initials: T
authors.lastname: Sata
mesh_terms: D000700:Analgesics / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D003929:Diabetic Neuropathies / Q000188:drug therapy*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006930:Hyperalgesia / Q000188:drug therapy; D007278:Injections, Spinal; D008297:Male; D009437:Neuralgia / Q000188:drug therapy*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000293:injuries; D013654:Taurine / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D000700:Analgesics; D013654:Taurine