Ultrastructural and Ultracytochemical Study of the Human Nasal Respiratory Epithelium in Vasomotor Rhinitis

• Published in: Acta oto-laryngologica Vol. 123; no. 8; pp. 943 - 949
• Main Authors: Giannessi, Francesco, Fattori, Bruno, Ursino, Francesco, Giambelluca, M. Anita, Soldani, Paola, Scavuzzo, Maria C., Ruffoli, Riccardo
• Format: Journal Article
• Language: English
• Published: Stockholm Informa UK Ltd 01-10-2003; Taylor & Francis; Taylor and Francis
• Subjects: Adult; Basement Membrane - metabolism; Basement Membrane - ultrastructure; Biological and medical sciences; Cilia - ultrastructure; Female; Humans; Male; Medical sciences; mucosa; Nasal Mucosa - enzymology; Nasal Mucosa - ultrastructure; nitric oxide; Nitric Oxide Synthase - metabolism; Non tumoral diseases; nose; Otorhinolaryngology. Stomatology; Rhinitis, Vasomotor - enzymology; Rhinitis, Vasomotor - pathology; Rhinitis, Vasomotor - surgery; Turbinates - metabolism; Turbinates - pathology; Turbinates - surgery; ultrastructure; Upper respiratory tract, upper alimentary tract, paranasal sinuses, salivary glands: diseases, semeiology; vasomotor rhinitis; Human; Nose disease; Respiratory epithelium; Pathogenesis; Cardiovascular disease; Cytochemistry; Electron microscopy; Vasomotor rhinitis; Vascular disease; Anatomic pathology; Ultrastructure; Nitric oxide; Nose; ENT disease; mucosa
• ISSN: 0001-6489; 1651-2251
• DOI: 10.1080/00016480310000737

Objectives-Several pieces of evidence have suggested that nitric oxide (NO) fulfills important functions in the respiratory mucosa, under both normal and pathological conditions. This study was performed to investigate the role of NO in the nasal respiratory epithelium of patients affected by vasomotor rhinitis. The structure and ultrastructure of the epithelium were also examined.
Material and Methods-The localization of NO synthase activity was determined by means of reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase ultracytochemistry. Nasal mucosa was obtained from patients who had undergone surgical therapy for reduction of the inferior turbinate.
Results-Examination of hematoxylin-eosin-stained sections revealed that most of the nasal mucosa covering the surgical samples was characterized by severe epithelial damage. The ultrastructural study confirmed the light microscopic observations. Ciliary loss, absence of the intercellular junctions and distension of the intercellular spaces were found in the damaged epithelium. The basement membrane was frequently interrupted. Some epithelial cells were identified as basal cells. Other cells of the damaged epithelium were probably involuted ciliated and goblet cells. The ultracytochemical study showed that the basal cells were NADPH-diaphorase-negative in healthy subjects and strongly NADPH-diaphorase-positive in subjects with vasomotor rhinitis.
Conclusions-It is suggested that NO has cytotoxic effects and causes inhibition of mitotic activity in the basal cells, leading to epithelial disruption and breakdown of the protective functions of the epithelium.