TY - JOUR

T1 - Histamine and tryptase in nasal lavage fluid after allergen challenge

T2 - effect of 1 week of pretreatment with intranasal azelastine or systemic cetirizine

AU - Jacobi, H H

AU - Skov, P S

AU - Poulsen, L K

AU - Malling, H J

AU - Mygind, N

PY - 1999/5

Y1 - 1999/5

N2 - BACKGROUND: Antihistamines (H1-receptor antagonists) act by competitive antagonism of histamine at H1-receptors. In addition, high concentrations of some antihistamines inhibit allergen-induced histamine release from mast cells in vitro.OBJECTIVE: The purpose of this study was to determine the effect of intranasal azelastine or systemic cetirizine (both potent antihistamines) on the allergen-induced release of mast-cell mediators from the human nasal mucosa in vivo.METHODS: Patients allergic to birch pollen (n = 11) and control subjects not allergic to birch pollen (n = 5) were included in a randomized, double-blind, placebo-controlled, 3-way crossover study outside the pollen season. Each subject was treated with azelastine nasal spray 0.14 mg per nostril twice daily, cetirizine tablets 10 mg every day, or placebo for 1 week using a double-dummy design. At the end of each treatment period, nasal allergen challenges were performed, and the number of sneezes were counted. In addition, nasal lavage fluid was collected, and the levels of mast-cell mediators (histamine and tryptase) were measured.RESULTS: The allergen challenge of patients allergic to pollen produced sneezing and a significant increase in the levels of histamine and tryptase. The challenge of subjects not allergic to pollen produced no such response. Azelastine and cetirizine significantly reduced allergen-induced sneezing and the associated increase in histamine and tryptase levels. No significant differences were found between the azelastine and cetirizine treatments.CONCLUSION: Pretreatment with azelastine or cetirizine inhibits the allergen-induced release of mast-cell mediators from the human nasal mucosa. Our results are consistent with the hypothesis that both antihistamines reduce mediator release from nasal mucosa mast cells in vivo. However, further studies are necessary to test this hypothesis.

AB - BACKGROUND: Antihistamines (H1-receptor antagonists) act by competitive antagonism of histamine at H1-receptors. In addition, high concentrations of some antihistamines inhibit allergen-induced histamine release from mast cells in vitro.OBJECTIVE: The purpose of this study was to determine the effect of intranasal azelastine or systemic cetirizine (both potent antihistamines) on the allergen-induced release of mast-cell mediators from the human nasal mucosa in vivo.METHODS: Patients allergic to birch pollen (n = 11) and control subjects not allergic to birch pollen (n = 5) were included in a randomized, double-blind, placebo-controlled, 3-way crossover study outside the pollen season. Each subject was treated with azelastine nasal spray 0.14 mg per nostril twice daily, cetirizine tablets 10 mg every day, or placebo for 1 week using a double-dummy design. At the end of each treatment period, nasal allergen challenges were performed, and the number of sneezes were counted. In addition, nasal lavage fluid was collected, and the levels of mast-cell mediators (histamine and tryptase) were measured.RESULTS: The allergen challenge of patients allergic to pollen produced sneezing and a significant increase in the levels of histamine and tryptase. The challenge of subjects not allergic to pollen produced no such response. Azelastine and cetirizine significantly reduced allergen-induced sneezing and the associated increase in histamine and tryptase levels. No significant differences were found between the azelastine and cetirizine treatments.CONCLUSION: Pretreatment with azelastine or cetirizine inhibits the allergen-induced release of mast-cell mediators from the human nasal mucosa. Our results are consistent with the hypothesis that both antihistamines reduce mediator release from nasal mucosa mast cells in vivo. However, further studies are necessary to test this hypothesis.

KW - Administration, Intranasal

KW - Adult

KW - Cetirizine

KW - Chymases

KW - Double-Blind Method

KW - Female

KW - Histamine

KW - Humans

KW - Inflammation Mediators

KW - Male

KW - Mast Cells

KW - Nasal Lavage Fluid

KW - Nasal Provocation Tests

KW - Phthalazines

KW - Premedication

KW - Serine Endopeptidases

KW - Time Factors

KW - Tryptases

KW - Clinical Trial

KW - Journal Article

KW - Randomized Controlled Trial

KW - Research Support, Non-U.S. Gov't

M3 - Journal article

C2 - 10329808

VL - 103

SP - 768

EP - 772

JO - Journal of Allergy and Clinical Immunology

JF - Journal of Allergy and Clinical Immunology

SN - 0091-6749

IS - 5 Pt 1

ER -