Ty- jour t1-人类旁鼻窦粘膜粘膜中的钙独立和抗性氮氧化物合酶活性 - 欧洲呼吸杂志weitzberg,e au -rinder,j au -rudehill,a au -jansson,o au -au -au -wiklund,np au -au -lundberg,jm au -au -au -au -alving,k y1-1996/07/01 ur -http://erj.ersjournals。com/content/9/7/1344.Abstract N2-人类鼻气道中存在一氧化氮(NO),主要源自副窦。免疫组织化学研究和信使核糖核酸(mRNA)原位杂交表明,在健康的窦上皮中,组成型2型NO合酶(NOS)。我们通过研究鼻窦粘膜活检中L-精氨酸向L-硫氨酸的酶促转化来进一步表征NOS活性。在重建性面部手术期间,从九名健康受试者获得上颌窦活检。此外,将九个对照中的鼻腔无浓度与五名接受高剂量糖皮质激素治疗的患者中发现的浓度进行了比较。最后,i.v.的影响L-精氨酸在鼻腔上输注未研究六名健康受试者。Ca(2 +) - 在所有活检中都发现了独立的NOS活性,比CA(2 +) - 依赖性活动高五倍(分别为179 +/- 64和36 +/- 17 PMOL.G-1。。对照组(344 +/-十亿分(PPB))和类固醇治疗的患者(342 +/- 36 ppb)之间的鼻腔无水平没有差异。 Nasal NO levels increased up to 35% following i.v. infusion of L-arginine. We conclude that NOS activity in healthy sinus mucosa is predominantly Ca(2+)-independent and this NOS is not downregulated by systemic steroids. Furthermore, L-arginine infusion increases nasal airway NO excretion in vivo, indicating that the substrate concentration is a rate-limiting factor under basal conditions. These findings further support the notion that sinus NOS is identical or very closely related to the type-2 NOS; however, the regulation of expression seems to be fundamentally different from that described previously for this NOS isoform. ER -