Sound induced expression of c-Fos in GABA positive neurones of the gerbil cochlear nucleus

To characterize c-Fos-expressing neurones in more detail, a double labelling technique was developed to simultaneously demonstrate the presence of GABA-like and c-Fos-like immunoreactivity in cryostat sections of the gerbil cochlear nucleus. The animals were exposed to a wide-band noise stimulus for the induction of c-Fos expression. The distribution of c-Fos-positive cells and GABA-positive somata was consistent with previous reports. Our double labelling approach revealed the presence of GABA-positive cells that showed c-Fos expression after noise stimulation. One interpretation of this finding is that a prolonged acoustic exposure induces long term changes in inhibitory interneurones to adjust the output of the cochlear nucleus.