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Author Spotlight: Extraction of Guinea Pig Round Window Membrane to Facilitate Inner Ear Drug Delivery Research
Published on: February 23, 2024
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Characterization of the Sheep Round Window Membrane
S Han1,2, H Suzuki-Kerr1,2, M Suwantika1,2
1Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.
Journal of the Association for Research in Otolaryngology : JARO
|December 1, 2020
Summary
The sheep round window membrane (RWM) shares anatomical similarities with the human RWM, suggesting its potential as a superior model for inner ear drug delivery research compared to rodents.
Area of Science:
- Otolaryngology
- Anatomy
- Pharmacology
Background:
- Intratympanic injection is a key method for delivering therapeutics to the inner ear.
- Drug diffusion across the round window membrane (RWM) is crucial for this delivery.
- Rodent RWM structure differs significantly from humans, limiting its translational value.
Purpose of the Study:
- To characterize the anatomical structure of the sheep round window membrane (RWM).
- To evaluate the suitability of sheep as a large animal model for inner ear drug delivery studies.
Main Methods:
- Histological examination of the sheep RWM structure.
- Measurement of RWM thickness and niche dimensions.
- Comparison of sheep RWM anatomy with existing human and rodent data.
Main Results:
- The sheep RWM is anchored in a niche with specific dimensions and has a curved shape.
- RWM thickness varies, being thinnest centrally (55-71 μm) and thicker at the edges (<171 μm).
- A layered structure (epithelial-connective tissue-epithelial) and a human-like meshwork structure were observed.
Conclusions:
- The sheep RWM exhibits significant anatomical similarities to the human RWM.
- Sheep represent a promising large animal model for predicting RWM permeability and drug delivery efficacy in humans.
- This model may offer greater translational relevance than rodent models for inner ear therapeutic development.
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