Publication Date
2006
Document Type
Thesis
Committee Members
Robert Fyffe (Advisor)
Degree Name
Master of Science (MS)
Abstract
This experiment analyzes synaptic differences in the central auditory pathway between normal hearing and congenitally deaf (dn/dn) mice, and provides valuable insight into central changes that correspond with human congenital deafness. Specifically, this experiment analyzes developmental expression of the Calcium (Ca2+)-binding proteins Calretinin (CR), Calbindin D-28k (CB) and Parvalbumin (PV) in large excitatory synapses in the anteroventral cochlear nucleus (AVCN) and the medial nucleus of the trapezoid body (MNTB) of normal and dn/dn mice. Immunofluorescence imaging with primary antibodies detecting CR, CB or PV was used to analyze the expression of each at 9 days, 13 days, 20 days, 30 days and 49 days postnatal in normal and dn/dn mice. Results indicated that Ca2+-binding expression was similar at each location in normal and dn/dn mice at 9 days postnatal, prior to opening of the ear canal and the onset of hearing (which occurs around 11 days postnatal) . In normal mice, patterns of Ca2+-binding protein expression changed progressively after the onset of hearing. In dn/dn mice (which completely lack auditory nerve activity), however, patterns of expression did not change after the onset of hearing, suggesting that patterns of Ca2+-binding protein expression change during development in normal mice in response to evoked auditory nerve activity, and that patterns of Ca2+-binding protein expression do not change during development in dn/dn mice due to lack of evoked auditory nerve activity. As a result, Ca2+ buffering is impaired in synapses located in the AVCN and MNTB of dn/dn mice.
Page Count
114
Department or Program
Department of Neuroscience, Cell Biology & Physiology
Year Degree Awarded
2006
Copyright
Copyright 2006, all rights reserved. This open access ETD is published by Wright State University and OhioLINK.
