title: Effects of chronic constriction injury and spared nerve injury, two models of neuropathic pain, on the numbers of neurons and glia in the rostral ventromedial medulla.
abstract: In previous studies we have reported that spinal nerve ligation (SNL), a model of neuropathic pain, results in the loss of over 20% of neurons in the rostral portion of the ventromedial medulla (RVM) in rats, 10 days after SNL. The RVM is involved in pain modulation and we have proposed that loss of pain inhibition from the RVM, including loss of RVM serotonin neurons, contributes to the increased hypersensitivity observed after SNL. In the present study we examined whether RVM neuronal loss occurs in two other models of neuropathic pain, chronic constriction injury (CCI) and spared nerve injury (SNI). We found no evidence for neuronal loss 10 days after either nerve injury, a time when robust tactile hypersensitivity is present in both CCI and SNI. We conclude that loss of RVM neurons appears not to be required for expression of tactile hypersensitivity in these models of neuropathic pain.
authors: Department of Neuroscience, University of Minnesota, 6-145 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, United States.
authors: Mai Lan
authors: ML
authors: Leong
authors: Department of Neuroscience, University of Minnesota, 6-145 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, United States.
authors: Rebecca
authors: R
authors: Speltz
authors: Department of Neuroscience, University of Minnesota, 6-145 Jackson Hall, 321 Church Street SE, Minneapolis, MN 55455, United States. Electronic address: martinw@umn.edu.
authors: Martin
authors: M
authors: Wessendorf
mesh_terms: D000818:Animals; D002452:Cell Count; D002908:Chronic Disease; D003251:Constriction, Pathologic; D004195:Disease Models, Animal; D006614:Hindlimb / Q000294:innervation; D006930:Hyperalgesia / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008526:Medulla Oblongata / Q000473:pathology*; D009437:Neuralgia / Q000473:pathology* / Q000503:physiopathology; D009457:Neuroglia / Q000473:pathology*; D009474:Neurons / Q000473:pathology*; D059348:Peripheral Nerve Injuries / Q000473:pathology* / Q000503:physiopathology; D010812:Physical Stimulation; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000293:injuries*; D013997:Time Factors; D014110:Touch
keywords: Apoptosis; Glia; Medulla; Neuropathy; Nociception; Pain