To understand how the DNA answers to external agents such as cisplatin may be relevant to the diagnosis and treatment of hearing disorders caused by the administration of such drug. OBJECTIVES: To investigate the cisplatin influence on the cochlea and DNA of guinea pigs. MATERIAL AND METHODS: Experimental study carried out with 12 guinea pigs (Cavia porcellus). The inclusion criterion was the presence of Preyer's reflex and distortion-product otoacoustic emissions. Guinea pigs were divided into two groups: Control Group (CG) - made up of six guinea pigs, to which we administrated saline solution during six consecutive days, intraperitoneally; and a Study Group (SG) - made up of six guinea pigs, to which we administrated cisplatin during six consecutive doses of 3mg/kg/day intraperitoneally. Twenty-four hours after the last administration of cisplatin the guinea pigs were slaughtered, blood samples were collected and the cochleae were removed. RESULTS: The administration of cisplatin did not cause identifiable changes to the DNA. Histological analysis showed changes in the organ of Corti and spiral ganglion. CONCLUSION: Cisplatin causes changes in cochlear histology, such as the loss of the normal micro-cytoarchitecture of the organ of Corti, and reduction of neurons of the spiral ganglion with cell alterations, however, DNA damage was not detected.
hair cells; auditory; genotoxicity; guinea pigs; histology