title: Morphologic changes in the inner ear of Chinchilla laniger after middle ear administration of gentamicin in a sustained-release vehicle.
abstract: The use of transtympanic gentamicin has become a popular method of treating Meniere's disease; nevertheless, many questions still remain regarding this therapy. Until investigators can control the exact amount of medicine that is administered to the ear and have an understanding of the kinetics of gentamicin, therapy will continue to rely on empirical data. Previously we described the use of a fibrin-based sustained-release vehicle impregnated with gentamicin in the middle ears of chinchillas. With this model a kinetics curve of gentamicin was defined. The inner ears of these animals were submitted for immunohistochemical and histologic analysis. We discuss the ultrastructural changes seen and correlate this to our kinetics data. We also examine measurement of hair cell damage with heat shock protein levels. By better understanding the actions of gentamicin in this animal model, we hope to facilitate safer use of intratympanic medicines in our patient population.
authors.affiliation: Department of Defense Spatial Orientation Center, Naval Medical Center San Diego, CA 92134-5000, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Hoffer
authors.forename: B J
authors.initials: BJ
authors.lastname: Balough
authors.forename: R D
authors.initials: RD
authors.lastname: Kopke
authors.forename: J
authors.initials: J
authors.lastname: Henderson
authors.forename: M
authors.initials: M
authors.lastname: DeCicco
authors.forename: D C
authors.initials: DC
authors.lastname: Wester
authors.forename: M J
authors.initials: MJ
authors.lastname: O'Leary
authors.forename: C
authors.initials: C
authors.lastname: Balaban
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000009:adverse effects* / Q000493:pharmacokinetics; D002682:Chinchilla; D003692:Delayed-Action Preparations; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D007758:Ear, Inner / Q000187:drug effects* / Q000648:ultrastructure*; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage* / Q000009:adverse effects* / Q000493:pharmacokinetics; D006198:Hair Cells, Auditory / Q000187:drug effects / Q000648:ultrastructure; D006360:Heat-Shock Proteins / Q000032:analysis; D007150:Immunohistochemistry; D007322:Instillation, Drug; D008297:Male; D008575:Meniere Disease / Q000188:drug therapy; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D003692:Delayed-Action Preparations; D005839:Gentamicins; D006360:Heat-Shock Proteins