Effects of repeated antigen exposure to sensitized rats on agonist-induced NO production and its downstream signaling in nasal mucosal veins
作者单位：Dept.of Pharmacol.Sch.of Pharm.Hoshi Univ.2-4-41 EbaraShinagawa-kuTokyo 142-8501Japan Dept.of Pharmacol.Sch.of Pharm.Hoshi Univ.2-4-41 EbaraShinagawa-kuTokyo 142-8501Japan Dept.of Pharmacol.Sch.of Pharm.Hoshi Univ.2-4-41 EbaraShinagawa-kuTokyo 142-8501Japan Dept.of Pharmacol.Sch.of Pharm.Hoshi Univ.2-4-41 EbaraShinagawa-kuTokyo 142-8501Japan
会议名称：《第十五届国际药理学大会》
会议日期：1000年
学科分类：1002[医学-临床医学] 100213[医学-耳鼻咽喉科学] 10[医学]
关 键 词：nitric oxide NOS allergic rhinitis nasal hyperresponsiveness
摘 要：正 In allergic rhinitis, nasal obstruction is considered to be induced by both a dilatation of plexus caverosum and an increase in vascular permeability in nasal mucosa. Nitric oxide （NO）,a powerful vasodilator, is suggested to be involved in allergic inflammation. In the present study, the effect of repeated antigen exposure on leukotriene D4（LTD4）-induced NO production in nasal mucosa was investigated. The changes in mRNA expression of NO synthase （NOS） isoforms in nasal mucosae of the antigen-induced nasal hyperresponsive rats were also determined by immunoblottings. The mRNA level of iNOS. but not eNOS and nNOS. was significantly increased in nasal mucosae of repeatedly antigen challenged rats. In addition, the LTD4-induced NO production in nasal mucosae of nasal hyperresponsive rats was markedly augmented as compared with that of control animals . Interestingly, the venodilatation induced by sodium nitroprusside. an NO donor, was also augmented in nasal hyperresponsive rats. Therefore, not only increased NO production but also enhanced NO responsiveness might be involved in the development of nasal hyperresponsiveness in allergic rhinitis.