Electrical Impedance and Expression of Tight Junction Components of the Nasal Turbinate and Polyp.

ABSTRACT

PURPOSE: We investigated the electrical impedance and expression of tight junction components of the turbinate mucosa, nasal polyp, and normal skin. PROCEDURES The inferior turbinate and nasal polyp of patients with chronic rhinosinusitis and the postauricular skin of patients with otitis media were examined. Electrical impedance was measured in vivo using a tissue conductance meter. Expressions of claudin-1 and tricellulin were examined by fluorescence immunohistochemistry and quantitative RT-PCR. RESULTS: Electrical impedance was higher in the skin than in the turbinate and polyp, but did not differ between the turbinate and polyp. Immunoreactivities for claudin-1 and tricellulin were seen in the epithelial/epidermal layer. Expression of claudin-1 was higher in the skin than in the turbinate and polyp. The polyp tended to show higher expression of claudin-1 but showed lower expression of tricellulin than the turbinate. The ratio of claudin-1 to tricellulin was highest in the skin and lowest in the turbinate. The correlation between expressions of the two tight junction components was strongly positive in the skin (r = 0.964) and negative (r = -0.527) in the turbinate and polyp. CONCLUSIONS: These results suggest that the roles of claudin-1 and tricellulin in barrier function may be complementary, and may thereby maintain a constant level of permeability of the mucosal tissues.