Immunochemical detection of glucocorticoid receptors within rat cochlear and vestibular tissues

A monoclonal antibody, BuGR2, to liver glucocorticoid receptor sites was tested for its reactivity and specificity in inner ear tissue supernatants by an Enzyme Linked Immuno Sorbant Assay (ELISA) and a Western blotting technique. Results demonstrated that this antibody specifically recognized a protein of 93 kDa in inner ear supernatant fractions, which conformed to the reported molecular weights of the glucocorticoid receptor in other tissues. Antigenic sites were determined to be higher within cochlear supernatant fractions compared to vestibular supernatant fractions by ELISA. This anti-glucocorticoid receptor antibody combined with the quantitative ELISA provides a sensitive means to further investigate the inner ear glucocorticoid receptor system.