CORE--OTOPATHOLOGY AND HISTOLOGY

University Of Michigan At Ann Arbor, Ann Arbor MI

Investigators

Linked publications & trials

Abstract

The purpose of the Otopathology/Histology Core is to provide expertise as well as coordinated and uniform assessments and experimental approaches for the histological methods common to Projects 0001, 0002 & 0003. The first aim is to determine the otopathology (histological changes) for Projects 0001, 0002 & 0003 to complement the functional assessments of hearing carried out in the Auditory Physiology Core. This will b accomplished with surface Preparations as a quantitative assessment of presence or absence of inner hair cells and outer hair cells (in all three rows) by position along the cochlear spiral. Data is viewed as a graph (cytocochleogram) and also provided as a percentage present at every location (observation point) in every cochlea. Furthermore, plastic para-modiolar sections are used for assessment of otopathology and age related changes for all cellular elements in the cochlea, including organ of Corti, auditory nerve/spiral ganglion cells and their peripheral processes, stria vascularis and lateral wall. Assessments are quantitative (Spiral ganglion cell numbers, strial width/thickness) and qualitative descriptions of pathological changes. The second aim is to determine the cellular localization of gene expression and proteins. Immunocytochemistry will be used for protein localization and in situ hybridization will be used to localize gene expression to specific cochlear cell types. Immunocytochemistry is performed on paramodiolar cryostat sections of the whole cochlea that allow immunostaining of all major cellular elements. Immunocytochemistry on surface preparations is used to provide additional "three dimensional" resolution of immunolocalization details in the organ of Corti. In situ hybridization is used to localize gene expression to specific cochlear cell types, performed on paramodiolar cryostat sections of the whole cochlea. Data will be reported to the Data Management and evaluated and discussed with all investigators.