Experimental reactivation of HSV-I in rat vestibular ganglia.

Rats with no clinical symptoms after inoculation were administered with cyclophosphamide in order to reactivate HSV-I in the vestibular ganglia. After this immunosuppression, the vestibular ganglia, trigeminal ganglia, cerebrum, cerebellum and brainstem were examined immunohistologically in order to detect HSV-I. HSV-I antigen could not be detected by using indirect immunofluorescence or the ABC method, however, it could be detected by using the PCR method. In this study, latent infection of HSV-I was shown but reactivation could not be established. We need further investigations to determine the reactivation of HSV-I in the vestibular ganglia, to obtain an animal model of vestibular neuronitis.