Recurrent hearing impairment and nystagmus induced by repeated antigen exposure in actively sensitized guinea pigs.

Although many studies have suggested a relation between allergy and Ménière's disease, the pathophysiology of this condition remains controversial. The aim of this study was to clarify whether an anaphylactic reaction in the inner ear can disturb hearing and equilibrium, and whether such disturbances recur in response to repeated anaphylactic reactions. Increases in audiological threshold, nystagmus, and endolymphatic hydrops were observed in response to a single exposure to antigen administered to actively sensitized guinea pigs. The increase in audiological threshold was maximal 10 h after antigen challenge (p < 0.005) and returned to the baseline level after 7 days. Nystagmus and the increase in audiological threshold induced by antigen exposure were inhibited by prior administration of pemirolast potassium (p < 0.05), an inhibitor of chemical mediator release from mast cells. A second challenge with antigen 7 days after the first also induced an increase in audiological threshold (p < 0.05) and nystagmus. These results suggest that studies of repeated antigen challenge in actively sensitized animal models may increase our understanding of the pathophysiology of Ménière's disease.