title: Carboplatin induces less apoptosis in the cochlea of guinea pigs than cisplatin.
abstract: BACKGROUND
  Cisplatin (CDDP) is known to cause inner ear damage while carboplatin (CBDCA) induces less ototoxicity than CDDP. We examined apoptotic changes in the cochlea of guinea pigs after injection of CDDP or CBDCA using immunohistochemical and electrophysiological techniques.
  
  
  METHODS
  Three days after the injection of each solution, the cochleas were immunohistochemically examined for the presence of fragments of single-stranded DNA (ssDNA). The auditory brain stem response was recorded before and three days after the injection.
  
  
  RESULTS
  We detected fragments of ssDNA in the stria vascularis and the spiral ligament of the CDDP-treated cochlea. In this group, the threshold of the auditory brainstem response was significantly elevated, however, in the CBDCA group, no apparent change of the threshold was detected. In the CBDCA group, fragments of ssDNA were detected in the stria vascularis and the spiral ligament. The number of cells that stained positive for ssDNA, was less than that in the CDDP group.
  
  
  CONCLUSIONS
  Our findings indicate that CBDCA induces less apoptosis than CDDP and that this phenomenon contributes to the ototoxicity of CDDP.
authors: Department of Oto-Rhino-Laryngology, Nippon Medical School, Tokyo, Japan. bxp02646@nifty.ne.jp
authors: Ken-chi
authors: KC
authors: Watanabe
authors: Ken
authors: K
authors: Jinnouchi
authors: Alexander
authors: A
authors: Hess
authors: Olaf
authors: O
authors: Michel
authors: Shunkichi
authors: S
authors: Baba
authors: Toshiaki
authors: T
authors: Yagi
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D016190:Carboplatin / Q000009:adverse effects / Q000494:pharmacology*; D002945:Cisplatin / Q000009:adverse effects / Q000494:pharmacology*; D003051:Cochlea / Q000166:cytology / Q000187:drug effects*; D004277:DNA, Single-Stranded / Q000187:drug effects; D016057:Evoked Potentials, Auditory, Brain Stem; D006168:Guinea Pigs; D007150:Immunohistochemistry
chemical_list: D000970:Antineoplastic Agents; D004277:DNA, Single-Stranded; D016190:Carboplatin; D002945:Cisplatin