Int J Physiol Pathophysiol Pharmacol 2011;3(2):71-87.
Original Article Localization of gentamicin uptake in the acutely isolated inner ear of the rat
Katharina Schmid, Jürgen Strutz, Otto Gleich, Pingling Kwok
Department of Otolaryngology - Head and Neck Surgery, University of Regensburg, Franz-Josef-Strauß-Allee 11, D-93042 Regensburg, Germany
Received February 25, 2011; accepted March 23, 2011; Epub March 28, 2010; Published June 30, 2011
Abstract: The quantitative analysis of fluorescence in frozen sections of rat inner ears exposed to Texas Red conjugated gentamicin revealed distinct gradients of gentamicin fluorescence. At 500 µg/ml gentamicin fluorescence occurred in inner and outer hair cells, the interdental cell region, the spiral limbus below the interdental cells, the nerve fiber bundle in the spiral lamina, the inner sulcus cells and the dorsal region of the spiral ligament. No gentamicin fluorescence was observed in the Hensen / Claudius cells, the ventral region of the spiral ligament, the stria vascularis and the spiral ganglion. In the vestibule only the hair cell epithelium and the transitional cells of the saccule showed gentamicin fluorescence while no gentamicin fluorescencewas found in hair cell epithelia and transitional cells of utricle and ampule, nerve fibers below hair cell epithelia of saccule, utricle and ampule and in dark cells. The gentamicin flurescence gentamicin increased at higher concentrations. Gentamicin exposure led to more pronounced gentamicin fluorescence in the cochlea compared to the vestibule. Based on the predominant gentamicin fluorescence in the hair cell - limbus region of the cochlea at a low dose we propose that gentamicin may interact with the K+-flow from the inner hair cells back to the scala media. (IJPPP1102003).
Key words: Gentamicin, Menière’s disease, cochlea, vestibule, rat
Address all correspondence to: Dr. Katharina Schmid Department of Otolaryngology, Head and Neck Surgery University of Regensburg, D-93053 Regensburg, Germany. Tel: +49-941-944-9410, Fax: +49-941-944-9431 E-mail: firstname.lastname@example.org