Experimental Reactivation of HSV-I in Vestibular Ganglia

Viral infection has been suggested to be one of the causes of vestibular neuronitis. In particular the possibility that reactivation of Herpes simplex virus (HSV) in vestibular ganglia causes vestibular neuronitis has been suggested. In this study, we inoculated HSV-I into the middle ear of rat and guinea pig. After the inoculation, 5 rats of 16 rats died within about 2 weeks. We observed 4 rats of 5 rats that showed nystagmus. One of the 4 rats with nystagmus showed head deviation to the inoculated side. Eleven rats and 8 guinea pigs with no clinical symptoms after inoculation were administered with cyclophosphamide <CP> in order to reactivate HSV-I in the vestibular ganglia. After the CP treatment, rats and guinea pigs didn't show any clincal symptoms. And we examined vestibular ganglia, trigeminal ganglia, cerebrum, cerebellum and brain stem by indirect immunofluoressence (IF) method and polymerase chain reaction (PCR) method. Unfortunately, HSV-I antigen could not be detcted by IF, but HSV-I DNA could be detected by PCR. Reactivatin of HSV-I wasen't shown, but latent infection of HSV-I was shown. From now on, to reactivate HSV-I in vestibular ganglia we will investigate the problem of the strain, the concentration of virus and the kinds of stimulation.

単純ヘルペスウイルスI型

前庭神経節

潜伏感染

再活性化

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