Expression And Distribution Of Aquaporin-3 In Nasal Polyps

Objective: Nasal polyps is a chronic inflammation disease of nasal mucosa with edema,inflammatory cell,infiltration and structural modifications of the epithelium (secretory hyperplasia and squamous metaplasia) and lamina propria (basement membrane thickening,extracelluar matrix accumulation,and fibrosis).The etiology and pathogenetic mechanisms of formation and growth of nasal polyps are still obscure.aquaporins(AQPs) is water channel expression in cell membrane of animals and plants.Aquaporins is a novel family of membrane protein which is in charge of the trans-portation of water across the membranes.Now at least 10 subtypes of AQPs were found,designated AQP0 through AQP9.AQP3 is widely distributed and it is expressed in kidney,bladder ,skin,sclera and inner ear etc.It was reported there is close relationship between AQP1,AQP2 and nasal polyp edema.The purpose of this study was to examine the expression and distribution of AQP3 in nasal polyps by immunohistochemical technique and to investigate the relation between AQP3 and nasal polyp edema.Methods: 32cases of normal inferior turbinates and 25 cases of normal middle turbinates and 87 cases of nasal polyps were used.In the group of nasal polyps,there were 25 cases of type â…¡phase 1,31 type â…¡phase 2,17 typeâ…¡phase 3 and 14 type â…¢;There are 53 cases of edematous type,19 cases of glandular type and 15 cases of cystic fibrous type according to histopathologic characteristics of nasal polyps.The expression and distribution of AQP3 in all groups were examined by immunohistochemical technique.Results: â‘ The positive rate of AQP3 and the number density in the epithelial cell layer from middle turbinate and inferior tubinate were higher than those from nasal polyps(p<0.01),whereas the gray score was on the contrary (p<0.01);In the group of nasal polyps,the positive rate of AQP3 and the number density from type â…¡ phase 1 were higher than those from type â…¡ phase 2 and type â…¡ phase 3(p<0.05) and the latter two were higher than those from type â…¢(p<0.05);The positive rate of AQP3 and the number density from glandular and cystic fibrous type were higher than those from edematous type (p<0.01). â‘¡The positive rate of AQP3 and the number density in the subepithelial tissue from nasal polyps were higher than those from middle turbinate and inferior tubinate (p<0.01),whereas the gray score was on the contrary (p<0.01);In the group of nasal polyps,the positive rate of AQP3 and the number density from type â…¢ were higher than those from typeâ…¡ phase 2 and type â…¡ phase 3(p<0.05) and the latter two were higher than those from typeâ…¡ phase 1 (p<0.05);The positive rate of AQP3 and the number density from edematous type were higher than those from glandular and cystic fibrous type (p<0.01).The differences between typeâ…¡ phase 2 and type â…¡ phase 3 were not significant (p>0.05),so were glandular and cystic fibrous type.â‘¢The differences between middle turbinate and inferior tubinate were not significant (p>0.05).Conclusion: The abnormal expression of AQP3 in nasal polyps may contribute to the genesis and development of nasal polyps.Comparison with the normal nasal mucosa from different part have no effect on the final results.