RESUMO
BACKGROUND AND OBJECTIVES: Electrolyte transport by nasal epithelia has been suggested to be important for controlling the quantity and composition of the nasal fluid and may play an important role in the development of nasal polyps. Transepithelial transport of ion and water in various fluid-transporting epithelia is strictly dependent on the localization of specific membrane proteins in the polarized epithelial cells. Na+ : HCO3-cotransporter (NBC) transports Na+ and HCO3- into the intracellular from extracellular space and induces the evacuation of H+, regulating pH. K+ : Cl- cotransporter (KCC) controls the cell volume and resorption of NaCl which is associated with the extracellular transport of K+ and Cl-. The present study evaluated the presense of mRNA for NBC and KCC in human inferior turbinate and nasal polyp. MATERIALS AND METHOD: The expression of NBC and KCC mRNA isoforms in inferior turbinate mucosa and nasal polyp was evaluated, using RT-PCR and in situ hybridization. RESULTS: RT-PCR revealed that the inferior turbinate and nasal polyp mucosa expressed kNBC, KCC1 and 4 mRNA. In in situ hybridization, their distribution was noted in the epithelial layer and submucosal glands of both mucosa. CONCLUSION: These results indicate that these types of ion transporters are expressed in human nasal mucosa and nasal polyp, controlling the fluid and ion transport in nasal epithelium and submucosal glands.