Effects of intrathecal injection of nicotine on the analgesic effects of isoflurane in a model of inflammatory pain.
The present study was designed to investigate the role of spinal neuronal nicotinic acetylcholine receptors in the analgesic effects of isoflurane. After having established the mice model of analgesia by intraperitoneally injecting (i.p.) appropriate doses of isoflurane, nicotine, a neuronal nicotinic acetylcholine receptor agonist was intrathecally injected. The effects of isoflurane and nicotine on paw licking times and formalin-induced c-fos expression in the spinal cord dorsal horn were examined. Our correlative studies have shown that isoflurane can decrease the paw licking times and simultaneously suppress c-fos expression after injection of formalin in the mice. Nicotine can partially antagonize the effects induced by isoflurane above. Spinal neuronal nicotinic acetylcholine receptors may be important targets for the analgesic effects of isoflurane in formalin pain.
Cheng
Wei
W
Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical College, Xuzhou 221002, China.
Yin
Qin
Q
Zeng
Yin-Ming
YM
Wang
Shu
S
Chen
Hong-Sheng
HS
Feng
Tao
T
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D005557:Formaldehyde; D007278:Injections, Spinal; D007530:Isoflurane / Q000494:pharmacology* / Q000627:therapeutic use; D051379:Mice; D009538:Nicotine / Q000008:administration & dosage / Q000494:pharmacology*; D010146:Pain / Q000188:drug therapy*; D017288:Pain Threshold / Q000187:drug effects; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis; D011978:Receptors, Nicotinic / Q000502:physiology; D013116:Spinal Cord / Q000737:chemistry / Q000187:drug effects
D000700:Analgesics; D016760:Proto-Oncogene Proteins c-fos; D011978:Receptors, Nicotinic; D005557:Formaldehyde; D009538:Nicotine; D007530:Isoflurane