OBJECTIVETo establish an in vitro model of mouse cochlear basilar membrane impairment using cisplatin, and observe the protective effect of methionine on the hair cells.

METHODSThe cochlear basilar membrane samples of thirty two Kunming mice were harvested on the 2nd day after birth and randomly divided into four groups. Each group had 16 samples. Overnight preincubation the cochlear organ followed by appropriate treatment respectively as follows: the serum-free culture medium, the serum-free culture medium with methionine and cisplatin, the cisplatinum-containing serum-free culture medium, and the methionine-containing serum-free culture medium. The protective effect of methionine for injury of cochlea hair cells induced by cisplatin was observed by myosin-VI immunofluorescence, light microscopy, laser confocal scanning microscope and hair cells counting.

RESULTSThe outer hair cells (OHC) and inner hair cells (IHC) of control group and methionine group were not damaged. The outer and inner hair cells of cisplatin group were damaged in various degree, and had remarkable difference compared with control group and methionine group (P < 0.05). The outer hair cells and inner hair cells of cisplatin + methionine group were damaged less than the cisplatin group with remarkable difference (t(IHC) = 3.929, t(OHC) = 8.582, P < 0.05).

CONCLUSIONSCisplatinum could damage the cochlear hair cells of the basal membrane in Kunming mice. Methionine might protect against cisplatin's damage on the cochlear hair cells.