Inhibitory effect of aerosol WP871 on SRS-A mediated bronchoconstriction in the guinea pig in vivo.
Slow-reacting substance of anaphylaxis (SRS-A) is an important factor mediating bronchoconstriction in asthma. We developed a guinea pig model for SRS-A mediated bronchoconstriction induced by antigen inhalation. Using this model, we investigated the effect of inhaled WP871, a new anti-allergic drug, on bronchoconstriction. Aerosol WP871 (0.01 and 0.033%) to some extent inhibited the antigen-induced bronchoconstriction in a dose-dependent fashion, but high-dose WP871 (0.1%) inhalation itself produced a non-specific bronchoconstriction. However, aerosol WP871 (0.033%) showed no inhibitory effect on bronchoconstriction caused by direct inhalation of leukotriene C4, a component of SRS-A. These findings indicate that aerosol WP871 does not antagonize SRS-A, but inhibits synthesis and/or release of SRS-A and has some non-specific bronchoconstrictive effect in high concentration.
Kurashima
K
K
Third Department of Internal Medicine, Kanazawa University School of Medicine, Japan.
Fujimura
M
M
Saito
M
M
Sakamoto
S
S
Miyake
Y
Y
Nishi
K
K
Matsuda
T
T
D000336:Aerosols; D000818:Animals; D001249:Asthma / Q000188:drug therapy*; D001393:Azoles / Q000276:immunology*; D004155:Diphenhydramine / Q000008:administration & dosage; D004306:Dose-Response Relationship, Immunologic; D006168:Guinea Pigs; D006633:Histamine Antagonists / Q000276:immunology / Q000378:metabolism; D007116:Immunization, Passive; D008297:Male; D010070:Oxalates; D013189:SRS-A / Q000276:immunology*; D013777:Tetrazoles / Q000008:administration & dosage / Q000276:immunology*
D000336:Aerosols; D001393:Azoles; D006633:Histamine Antagonists; D010070:Oxalates; D013189:SRS-A; D013777:Tetrazoles; D004155:Diphenhydramine; C065288:acitazanolast