Changes in protein expression in the vestibular nuclei during vestibular compensation.

In the guinea pig, labyrinthectomy induces an immediate depression of the resting discharges in the neurons of the ipsilateral vestibular nuclei. Later on, in spite of the persistent deprivation of their ipsilateral labyrinthine input, a spontaneous restoration of activity, which is complete within 1 week, occurs in these neurons. Here, by using computer-assisted quantitative two-dimensional gel analysis, we have detected three proteins whose expressions were increased in the ipsilateral vestibular nuclei 1 week after unilateral labyrinthectomy. The spatio-temporal pattern of this phenomenon was compatible with a role for it in the restoration of activity in the vestibular neurons deprived of their ipsilateral labyrinthine input. Furthermore, the N-terminal amino acid sequences of two of these expressed proteins were obtained.