134 Expression and Localization of CYSLT2 Receptor in Human Nasal Mucosa

BACKGROUND: We have previously reported the localization of CysLT1 receptor by using immunohistochemistry and in situ hybridization (Shirasaki H et al. Clin Exp Allergy. 2002;32:1007–1012). METHODS: To clarify the expression of CysLT2 receptor in human nasal mucosa, we investigated CysLT2 receptor mRNA expression and its protein localization in human nasal mucosa, by polymerase chain reaction (PCR) and immunohistochemistry.Human turbinates were obtained after turbinectomy from 6 patients with nasal obstruction refractory to medical therapy. Total RNA was isolated from human nasal mucosa, and CysLT2 receptor mRNA was detected in these tissues by using reverse transcriptase-PCR analysis. To identify the cells expressing CysLT2 receptor protein, double immunostaining was performed using anti-CysLT2 receptor antibody and anti-CD31 (endothelial cell) antibody. RESULTS: Reverse transcriptase-PCR analysis of total nasal RNA demonstrated the expression of CysLT2 receptor mRNA. The immunohistochemical studies revealed that anti-CysLT2 receptor antibody mainly labeled blood vessels. CONCLUSIONS: The results suggest a primary role for CysLT2 receptor as the vascular responses in upper respiratory tract.