Adjuvant agents enhance round window membrane permeability to dexamethasone and modulate basal to apical cochlear gradients
Nathan J Creber, Hayden T Eastwood, Amy J Hampson, Justin Tan, Stephen J O'Leary
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES | ELSEVIER SCIENCE BV | Published : 2019
Glucocorticoids have direct anti-inflammatory, anti-oxidant and anti-apoptotic effects on cochlear hair cells. Cochlear glucocorticoid therapy has gained particular attention for its ability to enhance the protection of residual hearing following hearing preservation cochlear implantation. Local drug delivery methods achieve high drug concentrations within the inner ear fluids but are reliant upon diffusion across the round window membrane. Diffusion has been shown to demonstrate large individual variability. This study explores the role of "adjuvant agents", which when administered with glucocorticoids, enhance inner ear absorption and distribution. Guinea pig cochleae were administered eit..View full abstract
The authors would like to thank Samantha Moreland for assistance with animal husbandry, Sam Issah for assistance with mass spectroscopy, and Elisha Thomas for advice on perilymph sampling. This work was supported by a scholarship from the Garnett Passe and Rodney Williams Memorial Foundation, Melbourne, Australia. The authors have no conflicts of interest to declare.