Cell proliferation in spiral ligament of mouse cochlea damaged by dihydrostreptomycin sulfate

Cell proliferation of the spiral ligament in the normal and drug-induced damaged mice cochleae was investigated using the mitotic tracer bromodcoxyuridine (BrdU). Only a few nuclei labelled by BrdU were seen in the spiral ligament of the control mouse. However, many BrdU labelled nuclei in the spiral ligament in the cochlea damaged by dihydrostreptomycin sulfate were found. The expression of Fibroblast Growth Factor receptor and connexin 43 was detected in the spiral ligament where BrdU labelled cells were found. These results suggest that cell proliferation in the spiral ligament may occur after the drug-induced damage, and this process is probably related to the recovery of cochlear function.