Hypertonic saline alters electrical barrier of the airway epithelium.
OBJECTIVE
The effect of tonicity changes in nebulizer solutions and irrigations on nasal mucosa is not well known. The present study aims to determine the basic mechanism of hypertonic solution on airway epithelial barrier.


METHODS
We investigated the electrical potential difference (PD) that is influenced by both active transport and the transepithelial electrical resistance of the epithelial mucosa in the human nose in vivo. The short circuit current (SCC) revealed net ion transport across the epithelium in the guinea pig trachea in vitro. Finally, the size dependency of macromolecules across the tracheal mucosa was determined in vitro using FITC-labeled dextrans of different sizes.


RESULTS
PD was significantly decreased after topical application of hypertonic solution both in human and in guinea pig nose. SCC was significantly decreased after application of hypertonic solution. The transport of these dextrans from the basolateral to the apical side was not increased significantly after apical application of hypertonic saline.


CONCLUSIONS
Hypertonic saline enhances the electrical permeability of the airway epithelial mucosa but not transport of macromolecule in the short term.
Miwa
Masato
M
Department of Otolaryngology, Dokkyo University School of Medicine, Koshigaya Hospital, Saitama, Tokyo, Japan.
Matsunaga
Mayumi
M
Nakajima
Noriyuki
N
Yamaguchi
Shintaro
S
Watanabe
Kensuke
K
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D003911:Dextrans / Q000378:metabolism; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives / Q000378:metabolism; D005456:Fluorescent Dyes / Q000378:metabolism; D006168:Guinea Pigs; D006801:Humans; D066298:In Vitro Techniques; D017136:Ion Transport / Q000187:drug effects*; D046911:Macromolecular Substances / Q000494:pharmacology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects*; D009079:Mucociliary Clearance / Q000187:drug effects; D020545:Respiratory Mucosa / Q000187:drug effects / Q000378:metabolism* / Q000502:physiology; D012462:Saline Solution, Hypertonic / Q000494:pharmacology*; D014132:Trachea / Q000378:metabolism* / Q000502:physiology
D003911:Dextrans; D005456:Fluorescent Dyes; D046911:Macromolecular Substances; D012462:Saline Solution, Hypertonic; C015219:fluorescein isothiocyanate dextran; D016650:Fluorescein-5-isothiocyanate