title: Thromboxane A2 production in allergen-induced immediate and late asthmatic responses. Its possible role in inducing the late response.
abstract: To determine whether thromboxane A2 (TXA2) participates in allergen-induced asthmatic responses, we measured plasma TXB2 levels during allergen-induced immediate and late asthmatic responses (IAR and LAR) in atopic asthmatics. We also examined the effect of a TXA2 synthetase inhibitor, OKY-046, on the responses. Plasma TXB2 levels increased in both IAR and LAR, being 2.2 times higher in LAR than in IAR. Plasma TXB2 levels in LAR reached the peak 4 hours after allergen challenge when FEV1 had just begun to decrease in LAR. OKY-046 inhibited both IAR and LAR with decreased plasma TXB2 levels. We conclude that TXA2 is produced in allergen-induced asthmatic responses and participates in the responses, especially in inducing LAR.
authors.affiliation: Second Department of Internal Medicine, Chiba University School of Medicine, Japan.
authors.forename: I
authors.initials: I
authors.lastname: Iwamoto
authors.forename: C
authors.initials: C
authors.lastname: Ra
authors.forename: T
authors.initials: T
authors.lastname: Sato
authors.forename: H
authors.initials: H
authors.lastname: Tomioka
authors.forename: S
authors.initials: S
authors.lastname: Yoshida
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000188:drug therapy / Q000276:immunology / Q000378:metabolism*; D001985:Bronchial Provocation Tests; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008689:Methacrylates / Q000627:therapeutic use; D013928:Thromboxane A2 / Q000096:biosynthesis* / Q000097:blood; D013930:Thromboxane-A Synthase / Q000037:antagonists & inhibitors; D013997:Time Factors
chemical_list: D000485:Allergens; D008689:Methacrylates; D013928:Thromboxane A2; D013930:Thromboxane-A Synthase; C034364:ozagrel