Dendrites of the auditory brainstem nucleus, nucleus laminaris (NL), exhibit rapid and highly selective degeneration in response to lesioning of their afferent fibers in vivo, suggesting that neuronal input is necessary for the maintenance of NL dendrite structure. The goal of the proposed research is to use electrophysiology and live, multi-photon imaging techniques to dynamically study the cellular mechanisms involved in this process, in the same cell over time. With this system, the time course and nature of the change in NL dendrite structure will first be characterized. Calcium imaging methods will then be used in combination with morphometric analysis of NL dendrites to begin assessing whether changes in calcium are spatially and/or temporally correlated with input-specific changes in dendrite structure. Pharmacological studies will also be conducted in order to determine which molecules are necessary for inducing localized changes in NL dendrites. The Rho GTPases, important regulators of cytoskeletal organization, will be of particular interest. Finally, the reversibility of the change in dendrite structure will be assessed by replacing input to degenerating NL dendrites and assessing whether they are able to re-grow.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
1F31DC007008-01
Application #
6835414
Study Section
Communication Disorders Review Committee (CDRC)
Program Officer
Sklare, Dan
Project Start
2004-06-15
Project End
2006-06-14
Budget Start
2004-06-15
Budget End
2005-06-14
Support Year
1
Fiscal Year
2004
Total Cost
$31,995
Indirect Cost
Name
University of Washington
Department
Physiology
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
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