title: Effect of increased pressure on tracheal ciliary beat frequency.
abstract: Effects of increased ambient pressure on mucociliary clearance have been poorly investigated. The effects of increasing pressures on ciliary beat frequency (CBF) of guinea-pig tracheal rings were studied in vitro. Increased pressures of 25 and 100 kPa induced a significant and equivalent enhancement of CBF from 30 min after the pressure increase. The increase in CBF observed after a pressure increase of 50 kPa (inspiratory oxygen fraction = 21%), was significantly greater than that observed with an equivalent oxygen tension at atmospheric pressure, i.e. with a gas mixture containing 30% oxygen. Addition of N(G)-nitro-L-arginine methylester (L-NAME) inhibited the enhancement in CBF observed after the 25 kPa pressure increase. Addition of L-arginine reversed the effect of L-NAME. These results demonstrate that a pressure increase applied to tracheal rings, in vitro, induces an enhancement of ciliary beat frequency and that generation of nitric oxide may be involved in this ciliary stimulation.
authors.affiliation: Labratoire de Physiopathologie Respiratoire, Centre d'Etudes du Bouchet, Vert-le Petit, France.
authors.forename: J H
authors.initials: JH
authors.lastname: Calvet
authors.forename: F
authors.initials: F
authors.lastname: Verra
authors.forename: J
authors.initials: J
authors.lastname: Maleine
authors.forename: M C
authors.initials: MC
authors.lastname: Millepied
authors.forename: A
authors.initials: A
authors.lastname: Harf
authors.forename: E
authors.initials: E
authors.lastname: Escudier
mesh_terms: D000818:Animals; D001120:Arginine / Q000494:pharmacology; D001274:Atmospheric Pressure; D002923:Cilia / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007552:Isotonic Solutions / Q000494:pharmacology; D008297:Male; D008858:Microscopy, Phase-Contrast; D018715:Microscopy, Video; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010100:Oxygen / Q000378:metabolism; D014132:Trachea / Q000187:drug effects / Q000502:physiology*
chemical_list: D004791:Enzyme Inhibitors; D007552:Isotonic Solutions; C037692:Tyrode's solution; D001120:Arginine; D019001:Nitric Oxide Synthase; D010100:Oxygen; D019331:NG-Nitroarginine Methyl Ester