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Contralateral spreading of substances following intratympanic nanoparticle-conjugated gentamicin injection in a rat model.

ABSTRACT: This study was performed to investigate the Eustachian tube as a potential route for contralateral spreading following intratympanic nanoparticle (NP)-conjugated gentamicin injection in a rat model. Sprague-Dawley rats were divided into three groups and substances were injected in the right ear: group 1 (fluorescent magnetic nanoparticles [F-MNPs], n?=?4), group 2 (F-MNP-conjugated gentamicin [F-MNP@GM], n?=?2), and control group (no injections, n?=?2). T2-weighted sequences corresponding to the regions of interest at 1, 2, and 3 h after intratympanic injection were evaluated, along with immunostaining fluorescence of both side cochlea. The heterogeneous signal intensity of F-MNPs and F-MNP@GM on T2-weighted images, observed in the ipsilateral tympanum, was also detected in the contralateral tympanum in 4 out of 6 rats, recapitulating fluorescent nanoparticles in the contralateral cochlear hair cells. Computational simulations demonstrate the contralateral spreading of particles by gravity force following intratympanic injection in a rat model. The diffusion rate of the contralateral spreading relies on the sizes and surface charges of particles. Collectively, the Eustachian tube could be a route for contralateral spreading following intratympanic injection. Caution should be taken when using the contralateral ear as a control study investigating inner-ear drug delivery through the transtympanic approach.

SUBMITTER: Lee SY

PROVIDER: S-EPMC7596480 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Contralateral spreading of substances following intratympanic nanoparticle-conjugated gentamicin injection in a rat model.

Lee Sang-Yeon SY Kim Jeonghyo J Oh Sangjin S Jung Gaon G Jeong Ki-Jae KJ Tan Tran Van V Hwang Dajeong D Kim SungIl S Song Jae-Jin JJ Suh Myung-Whan MW Lee Jaebeom J Koo Ja-Won JW

Scientific reports 20201029 1

This study was performed to investigate the Eustachian tube as a potential route for contralateral spreading following intratympanic nanoparticle (NP)-conjugated gentamicin injection in a rat model. Sprague-Dawley rats were divided into three groups and substances were injected in the right ear: group 1 (fluorescent magnetic nanoparticles [F-MNPs], n = 4), group 2 (F-MNP-conjugated gentamicin [F-MNP@GM], n = 2), and control group (no injections, n = 2). T2-weighted sequences corresponding to the ...[more]

PMID: 33122804

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Dataset Information

Contralateral spreading of substances following intratympanic nanoparticle-conjugated gentamicin injection in a rat model.

Publications

Contralateral spreading of substances following intratympanic nanoparticle-conjugated gentamicin injection in a rat model.

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