To investigate the neurotoxicity of intrathecal injections of dexmedetomidine,Sprague-Dawley rats were intrathecally injected with dexmedetomidine at doses of 0.75,1.50 and 3.00μg/kg into the spinal dorsal horn.We fo...To investigate the neurotoxicity of intrathecal injections of dexmedetomidine,Sprague-Dawley rats were intrathecally injected with dexmedetomidine at doses of 0.75,1.50 and 3.00μg/kg into the spinal dorsal horn.We found that c-Fos expression in the rat spinal dorsal horn peaked at 7 hours following the 3.00μg/kg dexmedetomidine injection,while the levels of c-Fos expression following 0.75 and 1.50μg/kg dexmedetomidine were similar to those in the spinal dorsal horn of normal rats. At 48 hours following administration,the level of c-Fos expression was similar to normal levels.In addition,the intrathecal injections of dexmedetomidine increased paw withdrawal mechanical thresholds and prolonged thermal tail flick latencies.These results indicate that dexmedetomidine has pronounced antinociceptive effects.However,dexmedetomidine appears to have neurotoxic effects in the spinal cord because it increased c-Fos expression in the spinal dorsal horn within 7 hours following administration.展开更多
Objective: To investigate the role of spinal glial cells activation in neuropathic pain in a recently developed spared nerve injury (SNI) animal model by Decosterd and Woolf. Methods: A lesion was made to two of the t...Objective: To investigate the role of spinal glial cells activation in neuropathic pain in a recently developed spared nerve injury (SNI) animal model by Decosterd and Woolf. Methods: A lesion was made to two of the three terminal branches of the sciatic nerve of rats (tibial and common peroneal nerves) leaving the sural nerve intact. Continuous intrathe-cal administration of propentofylline, a glial modulating agent, 1 d before and 5 d after operation, was performed to disrupt spinal cord glia function. The vehicle was intrathecally administrated as control. The paw withdrawal threshold to mechanical stimulation (paw withdrawal mechaical threshold PWMT), body mass and motor function were determined pre- and post-surgery. Results: It produced a prolonged mechanical allodynia in the medial and lateral part of the ipsilateral hind paw in SNL models. The treatment with propentofylline significantly prevented the development of mechanical allodynia located in either medial or lateral plantar surface. Rats in two groups showed normal motor function and body weight increase. Conclusion: SNI model can be applied as a useful method with little variance in searching the mechanism of neuropathic pain. These study suggest that spinal glia activation may contribute to mechanical allodynia induced by SNI.展开更多
文摘To investigate the neurotoxicity of intrathecal injections of dexmedetomidine,Sprague-Dawley rats were intrathecally injected with dexmedetomidine at doses of 0.75,1.50 and 3.00μg/kg into the spinal dorsal horn.We found that c-Fos expression in the rat spinal dorsal horn peaked at 7 hours following the 3.00μg/kg dexmedetomidine injection,while the levels of c-Fos expression following 0.75 and 1.50μg/kg dexmedetomidine were similar to those in the spinal dorsal horn of normal rats. At 48 hours following administration,the level of c-Fos expression was similar to normal levels.In addition,the intrathecal injections of dexmedetomidine increased paw withdrawal mechanical thresholds and prolonged thermal tail flick latencies.These results indicate that dexmedetomidine has pronounced antinociceptive effects.However,dexmedetomidine appears to have neurotoxic effects in the spinal cord because it increased c-Fos expression in the spinal dorsal horn within 7 hours following administration.
文摘Objective: To investigate the role of spinal glial cells activation in neuropathic pain in a recently developed spared nerve injury (SNI) animal model by Decosterd and Woolf. Methods: A lesion was made to two of the three terminal branches of the sciatic nerve of rats (tibial and common peroneal nerves) leaving the sural nerve intact. Continuous intrathe-cal administration of propentofylline, a glial modulating agent, 1 d before and 5 d after operation, was performed to disrupt spinal cord glia function. The vehicle was intrathecally administrated as control. The paw withdrawal threshold to mechanical stimulation (paw withdrawal mechaical threshold PWMT), body mass and motor function were determined pre- and post-surgery. Results: It produced a prolonged mechanical allodynia in the medial and lateral part of the ipsilateral hind paw in SNL models. The treatment with propentofylline significantly prevented the development of mechanical allodynia located in either medial or lateral plantar surface. Rats in two groups showed normal motor function and body weight increase. Conclusion: SNI model can be applied as a useful method with little variance in searching the mechanism of neuropathic pain. These study suggest that spinal glia activation may contribute to mechanical allodynia induced by SNI.
