Ultrastructural localization of gentamicin in the cochlea

doi:10.1016/0378-5955(90)90031-J

Hearing Research

Volume 50, Issues 1–2, December 1990, Pages 35-42

https://doi.org/10.1016/0378-5955(90)90031-J Get rights and content

Abstract

The ultrastructural distribution of gentamicin in the cochlea was investigated immunocytochemically. Specific labeling was restricted to the organ of Corti, in particular to the outer and inner hair cells, the Deiters' cells, Hensen's cells and the tympanic layer cells of the basilar membrane. Other cochlear tissues did not demonstrate any labeling. At the subcellular level, gentamicin was found in lysosomes, multivesicular bodies and small tubules and vesicles.

A model is proposed in which it is hypothesized that gentamicin is internalized by endocytotic vesicles and is transferred to the lysosomal compartment as well as to the endoplasmic reticulum and Golgi complex.

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Citation Excerpt :
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^☆: This work was presented, in part, at the 26th Workshop on Inner Ear Biology, 3–6 September 1989, Paris, France.

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Ultrastructural localization of gentamicin in the cochlea☆

Abstract

Am. J. Otolaryngol.

J. Ultrastruct. Res.

Kidney Int.

Hear. Res.

Am. J. Otolaryngol.

Hear. Res.

Biochem. Pharmacol.

Hear. Res.

Hear. Res.

Gentamicin-induced lysosomal phospholipidosis in cultured rat fibroblasts. Quantitative ultrastructural and biochemical study

Lab. Invest.

Uptake of 3H-dihydrostreptomycin by macrophages in culture

Infec. Immun.

Early effects of gentamicin on inner ear glycocalyx cytochemistry

Hear. Res.

Glycocalyx heterogeneity of the cochlea: Effects of endolymphatic sac obliteration and gentamicin treatment

Electron microscopy of the stria vascularis and its response to ethacrynic acid. A study using electron-dense tracers and extracellular surface markers

Audiology

Gentamicin alters membrane structure as shown by freeze-fracture of liposomes

Hear. Res.

Drug-induced ototoxicity

Br. J. Audiol.

An immunohistochemical method for the study of amioglycoside ototoxicity in the guinea pig cochlea using decalcified frozen sections

Arch. Otorhinolaryngol.

Distribution of gentamicin by immunofluorescence in the guinea pig inner ear

Arch. Otorhinolaryngol.

Voltage-dependent interaction of dihydrostreptomycin with the transduction channels in bullfrog sensory hair cells

J. Physiol.

Possible effects of various ototoxic drugs upon ATP-hydrolyzing system in the stria vascularis and spiral ligament of the guinea pig

Laryngoscope

Uptake of ³H-dihydrostreptomycin by macrophages in culture