title: Intrathecal L-arginine reduces the antinociception of sevoflurane in formalin-induced pain in rats.
abstract: The purpose of this study was to investigate the contribution of spinal nitric oxide (NO) to the antinociceptive effects of emulsified sevoflurane in rats. Formalin tests were used to assess the nociceptive response. Immunohistochemistry was performed to determine the effects of emulsified sevoflurane on formalin-induced changes of Fos-like immunoreactive (Fos-LI)-positive neurons in the spinal cord. We found that emulsified sevoflurane administered intraperitoneally at a dosage of 2.5 ml/kg did not impair motor performance in rats, but it significantly decreased the formalin-induced paw licking time. Furthermore, Fos-LI-positive neurons were mainly found in the ipsilateral dorsal horn after the injection of formalin. The administration of emulsified sevoflurane significantly decreased Fos-LI-labeled neurons. Finally, intrathecal L-arginine alone did not affect the basal pain threshold, but it significantly decreased the antinociceptive response of emulsified sevoflurane against formalin injection and the suppressive effects of sevoflurane on formalin-induced Fos protein expression (P<0.05). These data suggest that spinal cord NO is involved in the antinociception of sevoflurane in rats.
authors: Department of Anesthesiology, People's Hospital of Jiangyin, Jiangyin 214400, China; Jiangsu Province Key Laboratory of Anesthesiology, XuZhou Medical College, Xuzhou 221002, China.
authors: Jian-Qing
authors: JQ
authors: Chen
authors: Jiangsu Province Key Laboratory of Anesthesiology, XuZhou Medical College, Xuzhou 221002, China.
authors: Yin-Ming
authors: YM
authors: Zeng
authors: Jiangsu Province Key Laboratory of Anesthesiology, XuZhou Medical College, Xuzhou 221002, China.
authors: Ti-Jun
authors: TJ
authors: Dai
authors: Department of Anesthesiology, Suzhou BenQ Medical Center, Nanjing Medical University, Suzhou 215009, China. Electronic address: ably.tang@benqmedicalcenter.com.
authors: Qi-Feng
authors: QF
authors: Tang
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D007278:Injections, Spinal; D008738:Methyl Ethers / Q000494:pharmacology*; D009474:Neurons / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D059225:Nociception; D010146:Pain / Q000378:metabolism / Q000503:physiopathology*; D010147:Pain Measurement; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D000077149:Sevoflurane; D013116:Spinal Cord / Q000187:drug effects / Q000378:metabolism
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D016760:Proto-Oncogene Proteins c-fos; D009569:Nitric Oxide; D000077149:Sevoflurane; D001120:Arginine
keywords: Antinociception; Nitric oxide; Pain; Sevoflurane; c-Fos; l-arginine