Nasal nitric oxide does not control basal nasal patency or acute congestion following allergen challenge in allergic rhinitis.
Nasal nitric oxide (NO), a powerful vasodilator, could control the filling of nasal capacitance vessels, thus determining nasal patency and mediating the acute congestion accompanying allergen challenge. We examined the effect of topical N-nitro-L-arginine-methyl-ester (L-NAME; 100 to 200 mg), an NO synthase inhibitor, on nasal NO and on nasal patency assessed by acoustic rhinometry in 7 subjects with nasal allergy, and in 4 subjects we examined the effects of nasal allergen challenge on nasal NO before and after a short course of nasal steroid. After L-NAME, nasal NO fell to 42.1%+/-15.7% of baseline (p < .0001) with no significant change in minimal cross-sectional area. After allergen challenge, acute congestion was associated with a significant fall in nasal NO, which returned to baseline by 4 hours, when the congestion resolved. Repeat challenge after 2 weeks of nasal corticosteroid yielded similar findings. A role for NO in modulating vascular tone was not supported by the present study.
Silkoff
P E
PE
Department of Medicine, Faculty of Medicine, University of Toronto, Ontario, Canada.
Roth
Y
Y
McClean
P
P
Cole
P
P
Chapnik
J
J
Zamel
N
N
D000208:Acute Disease; D000281:Administration, Intranasal; D000328:Adult; D000485:Allergens; D001993:Bronchodilator Agents / Q000378:metabolism / Q000627:therapeutic use*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008365:Manometry / Q000379:methods; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D015508:Nasal Obstruction / Q000209:etiology*; D009299:Nasal Provocation Tests / Q000379:methods*; D009569:Nitric Oxide / Q000378:metabolism / Q000627:therapeutic use*; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications* / Q000175:diagnosis* / Q000188:drug therapy*; D013997:Time Factors; D014654:Vascular Patency / Q000187:drug effects*
D000485:Allergens; D001993:Bronchodilator Agents; D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D019331:NG-Nitroarginine Methyl Ester