Article

[Distribution of gentamicin in inner ear after intratympanic gentamicin injection].

Department of Otology and Skull Base, Eye Ear Nose and Throat Hospital, Fudan University, Shanghai 200031, China.
Zhonghua er bi yan hou tou jing wai ke za zhi = Chinese journal of otorhinolaryngology head and neck surgery 12/2006; 41(11):851-6. pp.851-6
Source: PubMed

ABSTRACT 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).
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.
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.
GTTR was a potential fluorescent probe to investigate the pharmacokinetics and mechanisms of gentamicin accumulation in local application.

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Keywords

Adult guinea pigs
 
Diffuse staining
 
gentamicin accumulation
 
guinea pig inner ear
 
infracuticular zone
 
inner ear
 
intact membrane
 
local application
 
local drug administration
 
local injection
 
middle ear cavity
 
outer hair cells
 
peak level
 
phalloidin-alexa-488
 
potential fluorescent probe
 
sensory cells
 
support cells
 
uptake
 
vestibular cells
 
vestibular organ