The long-term objectives are to understand the neurobiological role of insulin-like growth factor I (IGF-I), and investigate the potential usefulness of IGF-I in the management of neurodegenerative disorders and trauma to the nervous system. The major specific aims of this Project are to test the inter-related hypotheses that IGF-I gene expression helps to regulate synaptogenesis in mammals during development, that IGF-I gene expression mediates synaptogenesis modulated by nerve-muscle use and disuse, that IGF-I gene expression contributes to peripheral nerve regeneration rates, and that IGF-I can accelerate motor and sensory axon regeneration rates. The IGF-I gene is among only a few gene presently suspected of instructing the development and regeneration of vertebrates synapses, and might be regarded as a prototype gene regulating the turnover of vertebrate synapses. The wealth of data and simplicity of the neuromuscular junction makes it an appropriate model. These studies will be done in rats, mice, and embryonic chicks. The mechanisms of nerve regeneration is currently understood primarily at a descriptive level, and the results of this Project will contribute much needed data concerned with the molecular processes underlying peripheral nerve regeneration. Furthermore, the results are likely to suggest new therapeutic interventions for promoting more rapid and complete peripheral nerve regeneration, and will provide new concepts and theories to be tested by those concerned with regeneration in the central nervous system. Further light will be shed as well on the potential involvement of these factors in neurodegenerative disorders, particularly those involving loss of synapses, axons and dendrites, and neurons, such as diabetic neuropathy.

Project Start
Project End
Budget Start
Budget End
Support Year
2
Fiscal Year
1991
Total Cost
Indirect Cost
Name
Colorado State University-Fort Collins
Department
Type
DUNS #
112617480
City
Fort Collins
State
CO
Country
United States
Zip Code
80523
Bernstein, B W; DeWit, M; Bamburg, J R (1998) Actin disassembles reversibly during electrically induced recycling of synaptic vesicles in cultured neurons. Brain Res Mol Brain Res 53:236-51
Pu, S F; Zhuang, H X; Ishii, D N (1995) Differential spatio-temporal expression of the insulin-like growth factor genes in regenerating sciatic nerve. Brain Res Mol Brain Res 34:18-28
Williams, C V; Davenport, R W; Dou, P et al. (1995) Developmental regulation of plasticity along neurite shafts. J Neurobiol 27:127-40
Schmidt, M F; Kater, S B (1995) Depolarization and laminin independently enable bFGF to promote neuronal survival through different second messenger pathways. Dev Biol 168:235-46
Glazner, G W; Ishii, D N (1995) Insulinlike growth factor gene expression in rat muscle during reinnervation. Muscle Nerve 18:1433-42
Hassinger, T D; Atkinson, P B; Strecker, G J et al. (1995) Evidence for glutamate-mediated activation of hippocampal neurons by glial calcium waves. J Neurobiol 28:159-70
Ishii, D N; Glazner, G W; Pu, S F (1994) Role of insulin-like growth factors in peripheral nerve regeneration. Pharmacol Ther 62:125-44
Garcia, J; Beam, K G (1994) Measurement of calcium transients and slow calcium current in myotubes. J Gen Physiol 103:107-23
Carpenter, M K; Hassinger, T D; Whalen, L R et al. (1994) CNS white matter can be altered to support neuronal outgrowth. J Neurosci Res 37:1-14
Garcia, J; Tanabe, T; Beam, K G (1994) Relationship of calcium transients to calcium currents and charge movements in myotubes expressing skeletal and cardiac dihydropyridine receptors. J Gen Physiol 103:125-47

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