The expression and localization of heme oxygenase in the adult guinea pig cochlea.

Reverse transcription-polymerase chain reaction demonstrated the expression of heme oxygenase-1 and heme oxygenase-2 (HO-2) mRNA in the cochlea, but the former was considered to be much lower than the latter. The HO-2-like immunoreactivity was observed mainly in supporting cells in the organ of Corti and in the spiral ganglion cells. However, in the vascular walls of the cochlea little immunoreactivity was detected. These results suggest that HO-2 is involved in the auditory neurotransmission and micromechanics of the organ of Corti.