EFFECT OF STRESS ON COCHLEAR GLUCOCORTICOID PROTEIN - ACOUSTIC STRESS

Levels of glucocorticoid (GR) receptor protein were determined by a qu antitative enzyme-linked immunosorbent assay (ELISA) technique in inne r ear tissues of rats exposed daily to 85 dB SPL white noise for 4 hou rs on 3 consecutive days. GR levels in spiral ligament and organ of Co rti tissues were detected using a monoclonal antibody to the GR recept or, BuGR(2). A non-significant 13% decrease in GR levels of spiral lig ament tissues was observed in the noise exposed animals relative to un treated animals. A statistically significant decrease of 27% in GR pro tein levels was seen in the organ of Corti region (P < 0.03), however. There was a concomitant increase of serum corticosterone levels (P < 0.03) in noise exposed animals as opposed to those of controls. These results indicate a tissue specific response of GR receptor to acoustic stress. Inner ear GR protein therefore may be a useful marker in dete rmining the effect of stress on the inner ear. Finally, such data may be applicable to support the hypothesis that stress is an etiological agent in Meniere's disease.