GABA(A) receptor subunit expression in the guinea pig vestibular nucleus complex during the development of vestibular compensation.

The aim of this experiment was to investigate whether vestibular compensation following unilateral vestibular deafferentation (UVD) is associated with changes in the expression of GABA(A) receptor subunits in the guinea pig vestibular nuclear complex (VNC) at 2, 10, and 30 h post-surgery. Using Western blotting, the alpha1 and gamma2 subunits (but not the beta2 subunit) were detected in the VNC of labyrinthine-intact animals. However, there were no significant differences in the protein expression of the alpha1 and gamma2 subunits within the ipsilateral or contralateral VNC at any time post-UVD compared to sham and anesthetic controls. Furthermore, UVD did not induce the expression of the beta2 protein. These results suggest that vestibular compensation in guinea pig, as in the rat, is not associated with changes in the protein levels of the GABA(A) receptor subunits alpha1, beta2, and gamma2 in the VNC. However, a limitation of this study is that the Western blotting technique can detect only changes that are larger than 30% and therefore small changes cannot be excluded.