LACK OF EFFECT OF AMMONIUM GLYCYRRHIZINATE ON THE MORPHOLOGY OF OVINENASAL-MUCOSA IN-VITRO

Glycyrrhetinic acid derivatives are reported to be nasal absorption pr omoters (1). Effects of ammonium glycyrrhizinate (AMGZ) on the in vitr o morphology of ovine nasal mucosa were therefore examined by light an d electron microscopy. Nasal mucosa was stripped from the submucosa an d mounted in Ussing chambers. Exposure of the apical surface to 2% amm onium glycyrrhizinate (24 mM) for 90 min caused no histopathological c hanges to the nasal epithelium. Epithelial integrity remained intact a s evidenced by the continued presence of morphologically intact juncti onal complexes. No sloughing of the epithelial layer from the basement membrane was observed, and cilia and microvilli were not affected by treatment with AMGZ. The results indicate that short-term exposure in vitro to ammonium glycyrrhizinate caused no overt morphological damage to ovine nasal mucosa.