The long-term goal of this project is to determine the mechanisms underlying the gradual return of sensory function that sometimes occurs in human beings and other mammals following spinal cord injury. Anterolateral cordotomy, an operation used to treat pain in human cancer patients, is used as a model of controlled spinal injury in behaviorally trained rodents. In the rat, as in the human and non-human primate, approximately 50% of subjects develop delayed sensory recovery after an initially successful operation. This variability in recuperative potential provides the opportunity to differentiate between animals that recover and those that do not, with the purpose of identifying the specific factors that promote recovery from neural injury. This proposal examines the hypothesis that specific immediate early genes, or specific levels of growth promoters or growth inhibitors, may be related to delayed recovery following neural injury. The focus of these experiments is upon the spinal cord. Both immunohistochemical and molecular biological technique will be used to detect levels of gene expression and protein production. The specific questions to be asked are; 1) Does the intraspinal expression of the immediate early genes c-fos and c-jun following anterolateral cordotomy represent a specific or a non- specific injury response? Can such gene expression be correlated with the development of sensory recovery? In particular, a) what is the time course of gene expression? b) is the pattern of gene expression dependent upon lesion configuration? c) can levels of gene expression be correlated with functional recovery? 2) Do animals that recover sensory function after cordotomy show higher intraspinal levels of the neurite growth promoter PN-1, and lower intraspinal levels of the endogenously produced, neurite growth inhibitor thrombin, than animals that fail to recover? If neural recovery following spinal injury can be correlated with the expression of particular genes or with the production of specific proteins, than a potentially powerful avenue for patient treatment could become available.

Project Start
1998-06-01
Project End
2001-05-31
Budget Start
1997-10-01
Budget End
1998-09-30
Support Year
20
Fiscal Year
1998
Total Cost
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Type
DUNS #
078861598
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Arvanian, V L; Mendell, L M (2001) Acute modulation of synaptic transmission to motoneurons by BDNF in the neonatal rat spinal cord. Eur J Neurosci 14:1800-8
Vincler, M; Maixner, W; Vierck, C J et al. (2001) Estrous cycle modulation of nociceptive behaviors elicited by electrical stimulation and formalin. Pharmacol Biochem Behav 69:315-24
Vierck Jr, C J; Light, A R (2000) Allodynia and hyperalgesia within dermatomes caudal to a spinal cord injury in primates and rodents. Prog Brain Res 129:411-28
Arvanov, V L; Seebach, B S; Mendell, L M (2000) NT-3 evokes an LTP-like facilitation of AMPA/kainate receptor-mediated synaptic transmission in the neonatal rat spinal cord. J Neurophysiol 84:752-8
Berg, J S; Farel, P B (2000) Developmental regulation of sensory neuron number and limb innervation in the mouse. Brain Res Dev Brain Res 125:21-30
Shea, V K; Cai, R; Crepps, B et al. (2000) Sensory fibers of the pelvic nerve innervating the Rat's urinary bladder. J Neurophysiol 84:1924-33
Birder, L A; Perl, E R (1999) Expression of alpha2-adrenergic receptors in rat primary afferent neurones after peripheral nerve injury or inflammation. J Physiol 515 ( Pt 2):533-42
Mendell, L M (1999) Neurotrophin action on sensory neurons in adults: an extension of the neurotrophic hypothesis. Pain Suppl 6:S127-32
Mendell, L M; Johnson, R D; Munson, J B (1999) Neurotrophin modulation of the monosynaptic reflex after peripheral nerve transection. J Neurosci 19:3162-70
Shu, X Q; Llinas, A; Mendell, L M (1999) Effects of trkB and trkC neurotrophin receptor agonists on thermal nociception: a behavioral and electrophysiological study. Pain 80:463-70

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