Introduction of an experimental model for the rapid destruction of hair cells: the use of DPOAEs in assessment of rat ear function

the aim of thos survey is establishment of an animal model through which a rapid distortion of the hair cell of cochlea administering amikacin and furosemide and using distortion product otoacoustic emission (DPOAE) the functioning of rat’s ear would be assessed. Forty-eight male Sprague dawley rats (with average of weight 200-250g, 12 weeks post natal) were randomly divided into six equal groups. Except the control group the rest received 0.5mg/g, 0.75mg/g, 1mg/g, 1.25mg/g, and 1.5mg/g, of subcutaneous amikacin respectively. 30 minutes later every rat received 0.1mg/g of furosemide intrapritoneally. DPOAE of rats was measured prior to these injections and 72 hours later. Then tissue section of the rat’s cochlea was prepared.Data were analyzed by means of SPSS (version 17) and ANOVA test and paired sample T test at the significant level of p≤ 0.05. All the cases had a significant decrease in their DPOAE with the frequencies 2KHz-8KHz (p≤0.05).The most change in DPOAE was in rats which had received 1mg/g – 1.5mg/g amikacin. Histological studies approved distortion of hair cell even within the apical turn. To establish a deafness model due to losing hair cells, it is recommended to use a combination of 1mg/g amikacin and 0.1mg/g furosemide. Besides, DPOAE can be used to approve deafness.