Exposure to high concentrations of ammonia (NH) can cause life-threatening lung damages. The objective of this study was to establish a translational in vitro model for NH-induced lung injury. Precision-cut lung slices (PCLS) from rats were exposed to NH and toxicological responses and cell viability were quantified by analysis of LDH, WST-1, inflammatory mediators (IL-1β, IL-6, CINC-1, MMP-9, RAGE and IL-18), and by microscopic evaluation of bronchoconstriction induced by electric-field-stimulation (EFS) or methacholine (MCh). Different treatment strategies were assessed to prevent or reverse the damages caused by NH using anti-inflammatory, anti-oxidant or neurologically active drugs. Exposure to NH caused a concentration-dependent increase in cytotoxicity (LDH/WST-1) and IL-1β release in PCLS medium. None of the treatments reduced cytotoxicity. Deposition of NH (24-59 mM) on untreated PCLS elicited an immediate concentration-dependent bronchoconstriction. Unlike MCh, the EFS method did not constrict the airways in PCLS at 5 h after NH-exposure (47-59 mM). Atropine and TRP-channel antagonists blocked EFS-induced bronchoconstriction but these inhibitors could not block the immediate NH-induced bronchoconstriction. In conclusion, NH exposure caused cytotoxic effects and lung damages in a concentration-dependent manner and this PCLS method offers a way to identify and test new concepts of medical treatments and biomarkers that may be of prognostic value.
Copyright © 2021. Published by Elsevier B.V.

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