N-omega-nitro-L-arginine methyl ester increases airway responsiveness to serotonin but not to acetylcholine in cats in vivo

Citation
H. Aizawa et al., N-omega-nitro-L-arginine methyl ester increases airway responsiveness to serotonin but not to acetylcholine in cats in vivo, RESPIRATION, 68(3), 2001, pp. 286-291
Citations number
25
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cardiovascular & Respiratory Systems","da verificare
Journal title
RESPIRATION
ISSN journal
0025-7931 → ACNP
Volume
68
Issue
3
Year of publication
2001
Pages
286 - 291
Database
ISI
SICI code
0025-7931(200105/06)68:3<286:NMEIAR>2.0.ZU;2-B
Abstract
Background: We previously reported that N-omega-nitro-L-arginine methyl est er (L-NAME) enhances airway responsiveness to inhaled serotonin in cats tre ated with atropine and propranolol. Objective: To further elucidate the rol e of nitric oxide (NO) in airway responsiveness, we investigated whether L- NAME induces airway hyperresponsiveness to serotonin and acetylcholine (ACh ) in animals with intact innervation. Methods: Cats were anesthetized with pentobarbital sodium (50 mg/kg, i.p.), and mechanically ventilated. To asse ss airway responsiveness, we measured increase in total pulmonary resistanc e (Rr) produced by delivering serotonin or ACh aerosol to the airway, and d etermined PC200 (the concentration which caused a 200% increase in R-L). Re sults: The following results were obtained: (1) Airway responsiveness to se rotonin was significantly enhanced by the administration of L-NAME (100 mg/ kg) in animals treated with atropine and propranolol. (2) Airway responsive ness to serotonin was also significantly enhanced by L-NAME in animals with intact innervation. (3) In contrast, airway responsiveness to ACh was not changed by the addition of L-NAME in cats with intact innervation. Conclusi on: These results suggest that NO modulates nonspecific airway responsivene ss in animals with intact innervation, presumably by a reflex mechanism. Co pyright (C) 2001 S. Karger AG, Basel.