antigen-induced airway responses

YM976 is an orally active PDE4 inhibitor (IC50:2.2 nM)

YM 16638 is an orally active leukotriene (LT) antagonist with triglyceride-lowering and peroxisome-increasing effects that can be used to study antigen-induced early and late airway responses in allergic sheep.

Pirodomast is a thromboxane A (TXA2) synthase inhibitor. Pirodomast inhibits leukotriene (LT) D4, C4, E4 formation and thromboxane B2 (TXB2) activity, but is weakly or ineffectively antagonistic to guinea pig bronchospasm induced by histamine, methacholine, serotonin, LTC4, or platelet-activating factor. Pirodomast is a potential antiallergic compound. Pirodomast had only weak relaxant activity on guinea pig trachea in vitro. Pirodomast is a potential antiallergic compound that inhibits the protein hydrolyzing activity of trypsin in vitro, prevents antigen-induced immediate and late asthmatic responses in allergic sheep in vivo, and inhibits antigen-induced airway hyperresponsiveness to histamine and carbachol in allergic sheep.

APC 366 is a selective tryptase inhibitor (Ki = 7.1 μM). Tryptase is a serine protease released during mast cell degranulation, which reduces acute airway responses to allergens and can be used for asthma allergy treatment.