title: [Distribution of gentamicin in inner ear after intratympanic gentamicin injection].
abstract: OBJECTIVE
  To investigate uptake and accumulation of gentamicin by cells in the guinea pig inner ear after intratympanic injection using a fluorescent probe--gentamicin-Texas-red conjunction (GTTR).
  
  
  METHODS
  Adult guinea pigs (n = 80) were administered a single dose of GTrR to the middle ear cavity through the intact membrane and survived for 12 h, 24 h, 48 h, 3 d, 4 d, 7 d, 14 d and 28 d. The distribution of GTTR in the cochlear and vestibular cells was observed after staining with phalloidin-alexa-488. Texas Red and DMSO were injected into the tympanum as control.
  
  
  RESULTS
  Diffuse staining of gentamicin in the labyrinth was observed initially after local drug administration. At later time point the outer hair cells and sensory cells of vestibular organ were staining more densely than the support cells in the inner ear. The peak level of fluorescent density was reached 3 days after local injection. The GTTR was observed in the infracuticular zone.
  
  
  CONCLUSIONS
  GTTR was a potential fluorescent probe to investigate the pharmacokinetics and mechanisms of gentamicin accumulation in local application.
authors.affiliation: Department of Otology and Skull Base, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai 200031, China.
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Liu
authors.forename: Chun-Fu
authors.initials: CF
authors.lastname: Dai
authors.forename: Zheng-Min
authors.initials: ZM
authors.lastname: Wang
authors.forename: Fang-Lu
authors.initials: FL
authors.lastname: Chi
authors.forename: Jie
authors.initials: J
authors.lastname: Tian
authors.forename: Cui-Di
authors.initials: CD
authors.lastname: Da
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000633:toxicity; D007758:Ear, Inner / Q000378:metabolism*; D005456:Fluorescent Dyes; D005839:Gentamicins / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000633:toxicity; D006168:Guinea Pigs; D006198:Hair Cells, Auditory / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D005456:Fluorescent Dyes; D005839:Gentamicins