title: High nitric oxide production in human paranasal sinuses.
abstract: Nitric oxide (NO) is present in air derived from the nasal airways. However, the precise origin and physiological role of airway-derived NO are unknown. We report that NO in humans is produced by epithelial cells in the paranasal sinuses and is present in sinus air in very high concentrations, close to the highest permissible atmospheric pollution levels. In immunohistochemical and mRNA in situ hybridization studies we show that an NO synthase most closely resembling the inducible isoform is constitutively expressed apically in sinus epithelium. In contrast, only weak NO synthase activity was found in the epithelium of the nasal cavity. Our findings, together with the well-known bacteriostatic effects of NO, suggest a role for NO in the maintenance of sterility in the human paranasal sinuses.
authors.affiliation: Department of Physiology & Pharmacology, Karolinska Institute, Stockholm, Sweden.
authors.forename: J O
authors.initials: JO
authors.lastname: Lundberg
authors.forename: T
authors.initials: T
authors.lastname: Farkas-Szallasi
authors.forename: E
authors.initials: E
authors.lastname: Weitzberg
authors.forename: J
authors.initials: J
authors.lastname: Rinder
authors.forename: J
authors.initials: J
authors.lastname: Lidholm
authors.forename: A
authors.initials: A
authors.lastname: Anggåard
authors.forename: T
authors.initials: T
authors.lastname: Hökfelt
authors.forename: J M
authors.initials: JM
authors.lastname: Lundberg
authors.forename: K
authors.initials: K
authors.lastname: Alving
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D001120:Arginine / Q000008:administration & dosage / Q000031:analogs & derivatives; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D004791:Enzyme Inhibitors / Q000008:administration & dosage; D004848:Epithelium / Q000378:metabolism; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D017403:In Situ Hybridization; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D019331:NG-Nitroarginine Methyl Ester; D009297:Nasal Mucosa / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D010254:Paranasal Sinus Diseases / Q000378:metabolism; D010256:Paranasal Sinuses / Q000378:metabolism*; D010446:Peptide Fragments; D012333:RNA, Messenger / Q000378:metabolism; D012119:Respiration
chemical_list: D000911:Antibodies, Monoclonal; D004791:Enzyme Inhibitors; D010446:Peptide Fragments; D012333:RNA, Messenger; D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester