The overall goal of this proposal is to assess the impact of post-traumatic glia on hippocampal physiology. Traumatic brain injury (TBI) is associated with a wide variety of neurological deficits, including memory impairment, cognitive dysfunction and epilepsy. The pathophysiological bases of such abnormalities still remain largely unknown. However, altered hippocampal excitability appears to play an important role. While the majority of research effort focuses on neuronal and synaptic changes, normal neuronal function also depends on an accurate regulation of the extracellular ionic concentrations and cellular and extracellular volume. Glial cells have been shown to play a crucial role in the homeostasis of extracellular volume and ionic composition, in the regulation of brain tissue water content, and in determining neuronal excitability and function. In spite of such a paramount role of glia, little is known about the functional status of glial cells acutely and chronically following TBI. We propose to define the acute and chronic effects of TBI on hippocampal glial function with particular emphasis on: 1) temporal pattern of glial reactivity and their electrophysiological changes, 2) temporal pattern of neuronal and filial extracellular K+-homeostasis, 3) pathophysiological consequences on ion and water homeostasis, and 4) neuronal and glial cell volume regulation. Investigations on these post-traumatic changes will allow a more rational treatment to TBI.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS040823-03
Application #
6701804
Study Section
Special Emphasis Panel (ZRG1-BDCN-2 (01))
Program Officer
Kleitman, Naomi
Project Start
2002-02-15
Project End
2006-01-31
Budget Start
2004-02-01
Budget End
2005-01-31
Support Year
3
Fiscal Year
2004
Total Cost
$354,867
Indirect Cost
Name
University of Washington
Department
Neurosurgery
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
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D'Ambrosio, Raimondo; Fairbanks, Jared P; Fender, Jason S et al. (2004) Post-traumatic epilepsy following fluid percussion injury in the rat. Brain 127:304-14